BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors, nonprofit publishers, academic institutions, research libraries, and research funders in the common goal of maximizing access to critical research. The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle, a Threatened Brazilian Landscape Author(s): Claudia Maria Jacobi and Flávio Fonseca do Carmo Source: AMBIO: A Journal of the Human Environment, 37(4):324-326. 2008. Published By: Royal Swedish Academy of Sciences DOI: http://dx.doi.org/10.1579/0044-7447(2008)37[324:TCOIOT]2.0.CO;2 URL: http://www.bioone.org/doi/full/10.1579/0044-7447%282008%2937%5B324%3ATCOIOT %5D2.0.CO%3B2 BioOne (www.bioone.org ) is a nonprofit, online aggregation of core research in the biological, ecological, and environmental sciences. BioOne provides a sustainable online platform for over 170 journals and books published by nonprofit societies, associations, museums, institutions, and presses. Your use of this PDF, the BioOne Web site, and all posted and associated content indicates your acceptance of BioOne’s Terms of Use, available at www.bioone.org/page/terms_of_use . Usage of BioOne content is strictly limited to personal, educational, and non-commercial use. Commercial inquiries or rights and permissions requests should be directed to the individual publisher as copyright holder.
Transcript
BioOne sees sustainable scholarly publishing as an inherently collaborative enterprise connecting authors nonprofit publishers academic institutionsresearch libraries and research funders in the common goal of maximizing access to critical research
The Contribution of Ironstone Outcrops to Plant Diversity in the IronQuadrangle a Threatened Brazilian LandscapeAuthor(s) Claudia Maria Jacobi and Flaacutevio Fonseca do CarmoSource AMBIO A Journal of the Human Environment 37(4)324-326 2008Published By Royal Swedish Academy of SciencesDOI httpdxdoiorg1015790044-7447(2008)37[324TCOIOT]20CO2URL httpwwwbiooneorgdoifull1015790044-744728200829375B3243ATCOIOT5D20CO3B2
BioOne (wwwbiooneorg) is a nonprofit online aggregation of core research in the biological ecologicaland environmental sciences BioOne provides a sustainable online platform for over 170 journals and bookspublished by nonprofit societies associations museums institutions and presses
Your use of this PDF the BioOne Web site and all posted and associated content indicates your acceptance ofBioOnersquos Terms of Use available at wwwbiooneorgpageterms_of_use
Usage of BioOne content is strictly limited to personal educational and non-commercial use Commercialinquiries or rights and permissions requests should be directed to the individual publisher as copyright holder
Comment
This comment was not peer reviewed
Climate Change Policy IPCC Consensus IsNot Enough
Intergovernmental Panel on ClimateChange (IPCC) consensual scientificknowledge on climate change and itseffects is to some extent the known truthbut not necessarily the entire truth Con-sensual scientific knowledge is only aminimum common denominator for thou-sands of scientists of different disciplinesand thousands of studies that due to theirmultiplicity heterogeneity and complexi-ty may sometimes mismatch If wescientists and science managers just pros-ecute credibility and consensus we mayend up misguiding society For the sake ofhumanity we must also take into accountthe possibility of events and scenarios thathave not yet gained consensus It is ofcourse impossible to adapt to the worstpossibilities in any aspect of the globalchange However society must keep aneye on nonlineal steep catastrophic pos-sibilities and should prudently create areaction system that would mobilize peo-ple and resources to face unexpectedrapid and severe events We call here forthe implementation of such reaction policyby the United Nations (UN)
The IPCC has accomplished an incred-ible task in assembling scientific evidencesthat a climate change is occurring as aconsequence of CO2 emissions and land-use changes and showing that presenttrends can produce catastrophic effects ifthey continue in a near future The IPCCAR4 SYR Summary for Policymakers (1)states that lsquolsquoconfidence has increased thata 15ndash258C increase in global meantemperature above pre-industrial levelsposes significant risks to many uniqueand threatened systems including manybiodiversity hotspotsrsquorsquo and that lsquolsquokey vul-nerabilities may be associated with manyclimate sensitive systems including foodsupply infrastructure health water re-sources coastal systems ecosystems glob-al biogeochemical cycles ice sheets andmodes of oceanic and atmospheric circu-lationrsquorsquo This is quite clear
However the IPCC documents are farfrom clear for the reference values thatcould serve to guide mitigation andadaptation strategies that human societyshould implement in order to avoidnegative impacts From the IPCC state-ments policymakers could deduce that wemight try to limit warming to 28C abovepresent average temperature by stabilizingthe atmospheric CO2-equivalent around550 ppm This way we could avoidexcessively negative impacts on Earthsystems IPCC models suggest that a rise
of global carbon prices could serve tostabilize greenhouse gases at around 550ppm CO2-eq by 2100 This seems overlyoptimistic because we already have 450ppm CO2-eq right now with higher ratesof increase each year Recent data (2)indicate that the 28C and 550 ppm CO2-eqthresholds could be exceeded much beforethe end of the century
The consensus may be also too opti-mistic regarding impacts Let us focus forexample on one of the effects of theclimate change considered to be mostlikely sea-level rise It seems that in thisconsensual scenario the sea-level risemight be kept lower than 50 cm at theend of the century The IPCC AR4 SYRSummary for Policymakers indicates thatits moderate model predictions lsquolsquoexcludefuture rapid dynamical changes in iceflowrsquorsquo It recognizes that there are lsquolsquoicedynamical processes seen in recent obser-vations but not fully included in theassessed ice sheet modelsrsquorsquo and that lsquolsquotherisk of additional contributions to sea levelrise from both the Greenland and possiblyAntarctic ice sheets may be larger thanprojected by ice sheet models and couldoccur on century time scalesrsquorsquo This doesnot seem very worrying However scien-tific assessments that have not yet foundscientific consensus indicate that i) glacierscan run faster than expected (3) ii) whenice shelves split from the continent gla-ciers in that continent find no obstacleand there is an increase in the rate of icedischarge into the sea and iii) under theAntarctic ice there is a system of liquid-water lakes more or less interlinked andthere is a risk that a part of that waterwould also flow to the sea if obstacles areremoved These phenomena could producemuch steeper rises of sea level than thosepredicted by IPCC They are less probablebut they can occur Furthermore in theother pole the decrease of ice surface inthe Arctic Ocean is proceeding at anunpredicted rate because positive feed-backs are at work (4) In addition ofcourse there are many other examples ofpositive feedbacks that can act in otherEarth system processes For instance evenwith a mere 28C increase and a decrease inrainfall fire and droughts can become thedriving factors in desertification of theMediterranean and other semiarid regions
Meanwhile although some companiesand some nations are implementing pro-grams driving to a more sustainablemodel most activities around the worldcontinue to be run lsquolsquobusiness as usualrsquorsquo
ignoring even the consensual IPCC assess-ments A minimum of caution calls forhuman society to consider also scenariosresulting from scientific knowledge butthat have not gained consensus It isimpossible to adapt to any one of theworst possibilities or even to many ofthem but we must strongly recommendthat apart from using consensual scientificknowledge for most initiatives we takeinto account nonlineal steep catastrophicpossibilities and while doing that wedevelop a reaction system to face unex-pected fast changes mobilizing peopleand resources to fight these kind of events
The United Nations has already creat-ed the Hyogo Framework a plan of actionto advise policymakers of the differentcountries on reducing our collective vul-nerability to natural hazards and theGlobal Platform for Disaster Risk Reduc-tion in order to increase the commitmentof nations by advising them on ways tostrengthen public infrastructures coastalfacilities and homes to withstand moreextreme weather flooding and risingwaters and to develop better droughtmanagement better early warning systemsand evacuation plans stronger buildingcodes improved land and water manage-ment policies expanded disaster educationprograms for local communities etc Allof this should be backed by strongerinstitutions and proper funding even fromthe economic point of view A recentexpert study in the United States showsthat one dollar invested today in disasterrisk reduction saves four dollars in thefuture cost of relief and rehabilitationmdashabargain by any standard (J Holmes 2007First Session of the Global Platform forDisaster Risk Reduction) However na-tional commitments will be slow andmany countries do not have the means tofollow these recommendations Mean-while we need a UN environmentalemergency force including resources (peo-ple equipment money) for medical assis-tance and for fighting fire floods severedroughts and other hazards
A continuous multiscale multifactorialmonitoring of the Earth system is vital tokeep an eye on these not-yet-consensualpossible environmental changes and arenovated United Nations economic andpolitical effort is necessary to develop sucha reaction system These are two impor-tant challenges for science and society inthis emerging twenty-first century We callhere for their consideration After all thisis what is done in many other smaller-scale
Ambio Vol 37 No 4 June 2008 321 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
anthropic processes just consider thesecurity levels and reaction systems withwhich we build our bridges or our housesin earthquake prone areas Earth is now aclimate-quake prone area for us and manypeople are unable to defend themselvessinglehandedly
References and Notes
1 Intergovernmental Panel on Climate Change 2007Climate Change 2007 Synthesis Report Summary forP o l i c y m a k e r s ( h t t p www i p c c c h p d f assessment-reportar4ar4_syr_spmpdf)
2 Canadell JG Le Quere C Raupach MR FieldCB Bultenhuis ET Ciais Ph Conwayu TJGillett NP et al 2007 Contributions to acceleratingatmospheric CO2 growth from economic activity carbonintensity and efficiency of natural sinks Proc NatAcad Sci USA 104 18866ndash18870
3 Kerr RA 2007 Is battered Arctic Sea ice down for thecount Science 318 33ndash34
4 Overpeck JT Otto-Blesner BL Milner GH MohsDR Alley RB and Kiehl JT 2006 Paleoclimaticevidence for future ice-sheet instability and rapid sea-level rise Science 311 1747ndash1750
Jaume TerradasCenter for Ecological Research andForestry ApplicationsmdashDepartmentof Animal Biology Plant Biologyand Ecology
Edifici CUniversitat Autonoma de Barcelona08913 Bellaterra
Spainjaumeterradasuabcat
Josep PenuelasCenter for Ecological Research andForestry ApplicationmdashNationalResearch Council of Spain
Edifici CUniversitat Autonoma de Barcelona08913 BellaterraSpainjoseppenuelasuabcat
Synopsis
This synopsis was not peer reviewed
Grassland Classification in Naqu Prefectureof Tibet
Naqu Prefecture is a part of Tibet andcovers a vast territory with an averagealtitude of 4500 m (Fig 1) It is one of themost important centers for animal pro-duction in Tibet and carries about 692million head of various livestock on about286 900 km2 of native grasslands Yak andsheep are well adapted to the localenvironment and account for 40 and31 of livestock population in Tibetrespectively (1) However animal hus-bandry in Naqu prefecture has facedsevere development problems due to thecombined effects of grassland degradationlong cold seasons and economic con-straints including distance from marketcenters inadequate infrastructure anduncertain grassland tenure arrangements(2) To resolve some of these problemsfacing herdsmen and regional planners ajoint research effort by Naqu AnimalHusbandry Bureau and Gansu GrasslandEcological Research Institute (GGERI)was initiated in 1990 to improve produc-tion of grassland and livestock (3) Thispaper focuses on the results of a grasslandclassification survey that included anevaluation of grazing capacity and com-ments on relevant policy implications Theresearch approach adopted was a combi-nation of remote sensing technologies andtraditional field survey methods
Remote sensing technology was com-bined with field survey as the researchapproach used to overcome the problemsof the vast area and terrain diversity inNaqu The grassland classification wasmade using the results of interpretations
of Landsat images and field survey Itfollowed the procedures used in the ChinaGrassland Classification System that weredeveloped from a grassland classificationsystem used in the former Soviet Unionand modified for Chinese conditions (4 5)According to this system that is promul-gated by the Ministry of Agriculture (6)the grassland is classified in terms of zonalclimatic features degree of use by live-stock and characteristics of plant com-
munity There are three levels ofclassification units in this system The firstlevel (called lsquolsquoclassrsquorsquo) incorporates grass-lands with similar macrotopographicalcondition and landscape into one typethat mainly reflects the feature of aclimatic zone eg temperature and mois-ture Classes are subdivided at a secondarylevel into lsquolsquogroupsrsquorsquo according to theforaging attributes of plants for livestockuse and variation of mesotopography and
Figure 1 Naqu location map
322 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
soil The third classification unit (calledlsquolsquotypersquorsquo) divides groups with grasslanddensity based on dominant plant specieswithin the grass community
Grassland Classification
The native grasslands of Naqu Prefecturewere subdivided into 4 classes 10 groupsand 32 types The distribution of grasslandclasses was identical to the geographic-climatic zones and included bush meadowalpine meadow alpine steppe and desertsteppe which form a horizontal-zonalpattern
Bush Meadow
The bush meadow class is distributedmainly over the hilly areas in the easterncounties of Naqu (eg Jiali SuoxianBiru and Baqing) where the climate iswet and comparatively temperate Theannual precipitation ranges from 579 mmto 650 mm with 80 occurring in thegrowing season (200ndash224 d) Averageannual temperature ranges from 158C to358C Owing to the diversified ecologicalconditions caused by topographic varia-tion the farming systems are mixed withlarge areas of native pasture in the lowlandand river valleys already converted tograin and cash crops Wheat peas rapepotato millet corn and buckwheat aremajor crops in these counties as well astraditional highland barley Yak andTibetan sheep are the major grazinglivestock with yaks accounting for 40of the prefecture livestock because they areso well adapted to the wet climate andhighland conditions Cattle and horses arealso important although cattle are mainlykept for use as draft animals for cropcultivation The emergence of the mixedfarming systems has led to peasantsbecoming settled in villages which in turnhas resulted in the development of animalhusbandry methods that differ significant-ly from the traditional nomadism in thepure pastoral areas The use of lowlandsand river valleys for crop production hasshifted livestock grazing to the hilly areasAlthough the grasslands are abundantprecipitous terrain and forestry landsrestrict grazing activities to certain alti-tudes (between 4200 and 4600 m) andplaces with relatively gentle slopes (258)Grasslands with these features account for8 of total usable grassland area in theprefecture Within this restricted usablegrassland area one typical group grami-neae is identified On the north-facingslopes between 4300 and 4600 m Rhodo-dendron nivale Hook f are dominant inassociation with Sibiraea angustata Hand-Mazz Spiraea alpina Pall and Potentillafruticosa L which are often used by yakand cattle Above 4700 m herbs graduallyreplace the dominant bushes On thesouth-facing slopes between 4200 and4500 m Elymus nutans Griseb Festuca
ovina L and Poa annua L are dominantin association with Kobresia pygmaeaKobresia humilis and Sabina tibeticaKom Because of the high foraging valueof these herbs and the relatively warmconditions yaks sheep cattle and horsesare intensively grazed on the south-facingslopes in the summer periods causingsevere overgrazing In winter livestockare grazed near the villages on thescattered grassland in the valleys andlowlands and supplemented with cropresidues and hays
Alpine Meadow
Alpine meadow is distributed over theriver terraces valleys and alluvial fans inthe west parts of the four eastern countieslarge areas of Naqu and Nierong and partof Anduo County It is the major grass-land class for livestock production in theprefecture accounting for 43 of the totalusable grassland area Cyperaceae formthe most abundant and forageable groupwhich accounts for 73 of the grasslandarea in this class Four grassland groupswere identified in this class based on theforaging values of plants and the meso-topography This vegetation is widelydistributed over flatter highlands valleysand sunny sides of hills over an altituderange between 4000 and 5200 m in the eastand central parts (eg Biru Suoxian JaliBaqing Naqu Nierong and Ando) Theclimate is suitable for this grassland groupthat prefers cold and wet climatic condi-tions with a protracted cold season as longas 8 mo and average rainfall of 400 mmThe K pygmaea grassland is the majortype and provides the best summer andautumn grazing for sheep and yaks in theprefecture as a result of its high foragingvalue and flatter terrain Although thecomposition of the grassland is relativelycomplex K pygmaea generally dominatesthe community with Sarracenia purpureaPoligonum macrophyllum D Don and Enutans present as subdominants Somehigher producing Kobresia grasslands arecut for hay production Overgrazingdrought and rodents are thought to beresponsible for the severe degradation ofthis grassland type
The gramineae form the next importantgrassland group in the class of alpinemeadow Kobresia pygmaea has a strongecological adaptation that enables it todominate plant communities above 5300m with cushion plants as a subdominantThis vegetation is mainly distributed in thetransition zones between alpine meadowand steppe classes and located in thevalley lake basin and saline meadowsbetween 4500 and 5200 m Three types ofgrassland within this group were identifiedbased on the dominant species whichincluded E nutans Achnatherum hookeriKeng and Puccinella himalaica Tzvel
Evergreen shrubs are the third group inthe alpine meadow that is located on the
north-facing sides of hills with altitudebetween 4200 and 4600 m in the easterncounties These types of grassland usuallyprovide winter and spring grazing forlivestock
Deciduous shrubs are the last group ofalpine meadow Rhododendron nivale dom-inate this group and the areas with lesscanopy density are usually used forgrazing yak and cattle in the warm seasonThis group is mainly distributed on north-facing hills with altitude between 4600 and4900 m in Naqu Suoxian Biru Jiali andBaqing It is also distributed on the south-facing sides of hills at 4000 and 4500 mwith P fruticosa and Elsholtzia fruticosaKehd as the dominant species Cutting byfarmers for household fuel for a longperiod of time has reduced canopy densityover large areas that are now used asgrazing lands for sheep yak and cattleThe areas with altitude of 4600 to 4900 mare usually used as grazing in the warmseason and the grasslands below thesealtitudes are used in the cold season
Alpine Steppe
Alpine steppe accounts for 57 of thetotal grassland areas in the prefecture andis an important area of sheep and goatproduction It is mainly distributed in thecentral and west counties of WenbuShuanghu Shengzha Bange and Anduowhere the altitude ranges between 4400and 5000 m and the climate is cold dryand windy The annual rainfall increasesfrom 100 mm to 300 mm from west to eastPlant composition in this class is generallyless botanically complex than alpine mead-ow with only 5 to 15 species Gramineaeform a typical group in this class whichoccurs in the valleys river terraces lakebasins alluvial fans and lake plains to thesouthwest of Naqu Prefecture A repre-sentative species in this group is Spurpurea Cyperaceae dominated byCarex moorcroftii is usually distributednorthwest of Naqu prefecture Deciduoustrees and shrubs normally distributed inthe flood land and shady sides of the hillsare also used by livestock
Desert Steppe
Desert steppe is widely distributed in thesandy land of lake basins alluvial fansand slopes of hills between Kekexili andKunlun Mountains where the averagealtitude exceeds 5000 m and the climateis extremely cold and dry Annual rainfallaverages only 100 mm Grassland compo-sition is very simple and only includesthree to five species of which Carexcompacta with C moorcroftii and Spurpurea occur frequently Desert steppeareas are lsquolsquounpopulated areasrsquorsquo wherewildlife such as wild yak Tibetan wilddonkey Tibetan antelope wolf fox etcmay be found
Ambio Vol 37 No 4 June 2008 323 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
References and Notes
1 Statistical Bureau of Tibet 2005 Annual EconomicStatistical Data of Tibet Lasa Tibet Press (In Chinese)
2 Liu J Zhan J and Deng X 2005 Spatio-temporalpatterns and driving forces of urban land expansion inChina during the economic reform era Ambio 34 450ndash455
3 Gansu Grassland Ecological Research Institute 1991Grassland and Livestock Resources in Naqu Prefecture ofTibet Lanzhou Gansu Science and Technology Press(In Chinese)
5 Peng X 1985 The rules and systems of grasslandclassification in China Sichuan Grassland 2 13ndash15 (InChinese)
6 Zizhi H 1996 Introduction to Grassland ClassificationBeijing Agricultural Press (In Chinese)
7 This work has been supported by Chinarsquos Special Fundfor Major State Basic Research Project (2007CB714406)Knowledge Innovation Program of the Chinese Acade-my of Sciences (approved KZCX2-YW-313 and
KZCX1-Y-02) foundation of the Chinese State KeyLaboratory of Remote Sensing Science (KQ060006)
Wang LiwenThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 Chinawlw9585163com
Wei YaxingDepartment of Geography LiaoningNormal University Dalian 116029China
Niu ZhengThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 China
Synopsis
This synopsis was not peer reviewed
The Contribution of Ironstone Outcropsto Plant Diversity in the Iron Quadranglea Threatened Brazilian Landscape
INTRODUCTION
Due to the contribution of a hithertoneglected ecosystem one of the richestmineral provinces in the world at theheart of a center of floristic diversity mayprove much more diverse and vulnerablethan the current figures show
The Iron Quadrangle (local nameQuadrilatero Ferrıfero) located in south-east Brazil covers an area of approximate-ly 7200 km2 and represents one of the mostimportant and well-studied geological siteson the planet It is contained entirelywithin the wealthy state of Minas Geraisthe area of which is approximately 587 000km2 larger than France The Portuguesename lsquolsquogeneral minesrsquorsquo attests to thehistorical ties of this state with the miningindustry since colonial times Constitutedby very oldmdashArchean and Paleoprotero-zoicmdashterrains the Iron Quadrangle land-scape is presently a mosaic at the ecotoneof two Brazilian hotspots Cerrado andAtlantic Forest which have been pro-foundly transformed by human activitiesnamely urbanization and mining
The region is one of the leadingproducers of metallic minerals in theworld especially superficial iron ore Theintense mining activity entails a completealteration of the landscape with enormousimpacts on the local and regional biodi-versity The superficial iron crusts locallyknown as canga are the result of weath-
ering of minerals derived from banded-iron formations (BIFs) compact hematiteand limonite (1) and they are distributedon the tops and sides of some mountainsformed by the huge deposits of iron orethat set the limits of the Iron QuadrangleThese outcrops form islands on top of hillsat altitudes ranging from 1000 to2000 m
Currently there are about 50 iron-oreopencast mines the extents of which mayreach 2000 ha Opencast mining is highlyaggressive to the environment because theironstone outcrops and their associatedbiota are discarded so that the iron-oredeposits can be reached and the excava-tions can reach 300 m depth and exposethe water table Furthermore the wastederived from these activities contaminates
nearby watersheds with heavy metals andtoxic elements (2)
These outcrops harbor characteristicrupestral vegetation which is shrub-dom-inated together with a large number ofsedges grasses and orchids most of whichare epilithic Due to their very restrictedarea difficult access and because they areassociated with high-quality iron-ore de-posits the plant communities over cangaare among the most threatened and leaststudied in the otherwise thoroughly sur-veyed ecosystems of southeast BrazilUntil recently rupestral plant communi-ties in the region had been given nodifferentiation with respect to the type ofsubstrate that harbored them Henceplants growing over iron ore were fre-quently recorded together with those
General landscape of the Iron Quadrangleviewed from an ironstone outcrop
Partial view of an opencast iron-ore mineshowing the superficial crust removal
324 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
growing over sandstone or granite Thehistorical lack of differentiation amonglithologies has prevented us from fullycomprehending the role of the flora andfauna biodiversity associated with theseironstone outcrops Recent studies how-ever have begun to reveal that the plantcommunities over ironstone outcropswhich are almost exclusively found in theIron Quadrangle with exception of Car-ajas in north Brazil (equally threatened byiron-ore mining) have a floristic identityand an extremely high local and regionaldiversity that equals or surpasses those ofthe other two lithologies
Preliminary comparative surveysamong the two major outcrop types inthe Iron Quadrangle sandstone and iron-stone suggest that the plant communitiesestablished over the latter contribute moreheavily to the biodiversity of the regionthan had been previously imagined Inonly six ironstones outcrops recentlysurveyed which together barely reach100 ha 430 angiosperm species distributedamong 78 families were catalogued Thisnumber represents 36 of all the familiesin Brazil the country with the highestplant diversity Notably some of thesespecies are endemic to very few outcropswithin the Iron Quadrangle such as themilkweed Ditassa monocoronata and thecactus Arthrocereus glaziovii These sur-veys illustrate the need to acceleratestudies of this particular environmentwhich in contrast to the well-documentedand world-known sandstone outcrops (thepredominant rock type in the area) isundergoing increasing economic pressure
WHY RESEARCH IRONSTONEOUTCROPS
The Iron Quadrangle makes up thesouthern end of an orographic groupknown as Espinhaco Range which isrecognized as one of the regions withhighest floristic diversity in South Amer-ica having more than 30 endemicspecies most of which are associated withrock outcrop environments (3) Theseamong other peculiarities recently grantedthe Espinhaco Range the status of Bio-sphere Reserve by the United NationsEducational Scientific and Cultural Orga-nization
Following this lead and with the aim ofestablishing their identity an ongoingproject at the Federal University of MinasGerais is devoted to determining thecontribution of the flora on ironstoneoutcrops to the regional plant diversityand to ascertaining the conservation statusof these ecosystems throughout the IronQuadrangle The initiative which com-bines botanists and ecologists has alreadyrevealed a very high local diversity show-ing astonishing numbers such as 16species of vascular plants in a single squaremeter This variety is the result of the smallsize of plants the rich matrix in which theyare embedded and the mineral andtopographical heterogeneity of these out-crops which create distinct microhabitatsside by side and result in a uniqueassociation of plants (4) Aside from themore typical communities that are alsocommon to other lithologies virtuallynothing is known about two plant com-munities typical of ironstone outcropstemporal ponds and penumbral rockcommunities associated with cliffs andcave entrances
The high diversity contrasts with thesevere edapho-climatic conditions typicalof outcrops in general such as highultraviolet (UV) intensities daily thermalsubstrate variations that can reach 458Crapid water loss and poorly developed soilcover which in the case of ironstones arefurther aggravated by a high content ofheavy metals One of the most relevantplant communities for conservation inregions with intense mining activities aremetallophyle plants which encompassthose species that have mechanisms ofresistance tolerance or bioaccumulationregarding metals usually taxa that areendemic to metalliferous areas Thesecommunities are being investigated forecological services such as phytoextrac-tion phytostabilization and phytopro-spection At present several researchgroups are focusing on the conservationand sustainable use of these communitiesfollowing the recommendations of theConvention on Biological Diversity toidentify and conserve metallophyles Theserecommendations have even been pro-posed for inclusion in the EnvironmentalManagement System ISO 14 000 (5) Thisproposal is fundamental to the short-termconservation of plant communities onironstone outcrops because to date thereis no specific environmental legislationthat protects this ecosystem In Brazilthere are important regions with rockoutcrops rich in metals like the Iron
Quadrangle itself However metallophylecommunities in spite of their evidentenvironmental importance have yet tobecome the focus of attention
Aside from the applications for sus-tainable use or for recovery of areasdegraded by mining the isolation amongoutcrops and plant and physiologicaladaptations make these environments amodel system for fundamental ecologicaland evolutionary questions such as pat-terns of species richness and distributionof species
BIODIVERSITY LOSS AND CON-SERVATION STATUS
Habitat loss and alteration have long beenrecognized as leading threats to worldbiodiversity In Brazilian ironstone out-crops this process occurs basically inassociation with mining activities Recent-ly this historical regional vocation hasbeen heavily accelerated as a consequenceof the economic emergence of Chinawhich has generated unprecedented de-mand for raw materials worldwide inparticular high-quality iron ore a phe-nomenon that has been termed lsquolsquothe Chinaeffectrsquorsquo in the commodities jargon Miningactivities contribute heavily to the Brazil-ian gross domestic product (GDP) In2000 the iron ore produced in the regionaccounted for 12 of the total value ofBrazilian mineral production excludingthe fossil fuels petroleum and gas (6)
Most floristic surveys of ironstoneoutcrops in the Iron Quadrangle are veryrecent Of the handful outcrops surveyedonly one is located within a conservationunit The others are located in areas ownedby mining companies which unfortunatelyreflects the vulnerable status of thisecosystem The mineral rights granted toindustry until 2002 cover an area of207 000 ha of the Iron Quadrangle Thisrepresents roughly 28 of the total IronQuadrangle area and probably 90 of allironstone outcrops in the region andillustrates that iron-ore exploitation over-laps heavily with these environments
Currently there are nine national parksin southeast Brazil that contain rockoutcrops and these are distributedthroughout extensive mountain rangessuch as the Mantiqueira and Serra doMar (granite outcrops) and Canastra andEspinhaco (sandstone outcrops) whichtogether cover 679 000 ha In the stateof Minas Gerais alone there are 14 stateparks that together cover around 212 000
Table 1 Public conservation units in southeast Brazil containing rock outcrops
Ambio Vol 37 No 4 June 2008 325 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
Comment
This comment was not peer reviewed
Climate Change Policy IPCC Consensus IsNot Enough
Intergovernmental Panel on ClimateChange (IPCC) consensual scientificknowledge on climate change and itseffects is to some extent the known truthbut not necessarily the entire truth Con-sensual scientific knowledge is only aminimum common denominator for thou-sands of scientists of different disciplinesand thousands of studies that due to theirmultiplicity heterogeneity and complexi-ty may sometimes mismatch If wescientists and science managers just pros-ecute credibility and consensus we mayend up misguiding society For the sake ofhumanity we must also take into accountthe possibility of events and scenarios thathave not yet gained consensus It is ofcourse impossible to adapt to the worstpossibilities in any aspect of the globalchange However society must keep aneye on nonlineal steep catastrophic pos-sibilities and should prudently create areaction system that would mobilize peo-ple and resources to face unexpectedrapid and severe events We call here forthe implementation of such reaction policyby the United Nations (UN)
The IPCC has accomplished an incred-ible task in assembling scientific evidencesthat a climate change is occurring as aconsequence of CO2 emissions and land-use changes and showing that presenttrends can produce catastrophic effects ifthey continue in a near future The IPCCAR4 SYR Summary for Policymakers (1)states that lsquolsquoconfidence has increased thata 15ndash258C increase in global meantemperature above pre-industrial levelsposes significant risks to many uniqueand threatened systems including manybiodiversity hotspotsrsquorsquo and that lsquolsquokey vul-nerabilities may be associated with manyclimate sensitive systems including foodsupply infrastructure health water re-sources coastal systems ecosystems glob-al biogeochemical cycles ice sheets andmodes of oceanic and atmospheric circu-lationrsquorsquo This is quite clear
However the IPCC documents are farfrom clear for the reference values thatcould serve to guide mitigation andadaptation strategies that human societyshould implement in order to avoidnegative impacts From the IPCC state-ments policymakers could deduce that wemight try to limit warming to 28C abovepresent average temperature by stabilizingthe atmospheric CO2-equivalent around550 ppm This way we could avoidexcessively negative impacts on Earthsystems IPCC models suggest that a rise
of global carbon prices could serve tostabilize greenhouse gases at around 550ppm CO2-eq by 2100 This seems overlyoptimistic because we already have 450ppm CO2-eq right now with higher ratesof increase each year Recent data (2)indicate that the 28C and 550 ppm CO2-eqthresholds could be exceeded much beforethe end of the century
The consensus may be also too opti-mistic regarding impacts Let us focus forexample on one of the effects of theclimate change considered to be mostlikely sea-level rise It seems that in thisconsensual scenario the sea-level risemight be kept lower than 50 cm at theend of the century The IPCC AR4 SYRSummary for Policymakers indicates thatits moderate model predictions lsquolsquoexcludefuture rapid dynamical changes in iceflowrsquorsquo It recognizes that there are lsquolsquoicedynamical processes seen in recent obser-vations but not fully included in theassessed ice sheet modelsrsquorsquo and that lsquolsquotherisk of additional contributions to sea levelrise from both the Greenland and possiblyAntarctic ice sheets may be larger thanprojected by ice sheet models and couldoccur on century time scalesrsquorsquo This doesnot seem very worrying However scien-tific assessments that have not yet foundscientific consensus indicate that i) glacierscan run faster than expected (3) ii) whenice shelves split from the continent gla-ciers in that continent find no obstacleand there is an increase in the rate of icedischarge into the sea and iii) under theAntarctic ice there is a system of liquid-water lakes more or less interlinked andthere is a risk that a part of that waterwould also flow to the sea if obstacles areremoved These phenomena could producemuch steeper rises of sea level than thosepredicted by IPCC They are less probablebut they can occur Furthermore in theother pole the decrease of ice surface inthe Arctic Ocean is proceeding at anunpredicted rate because positive feed-backs are at work (4) In addition ofcourse there are many other examples ofpositive feedbacks that can act in otherEarth system processes For instance evenwith a mere 28C increase and a decrease inrainfall fire and droughts can become thedriving factors in desertification of theMediterranean and other semiarid regions
Meanwhile although some companiesand some nations are implementing pro-grams driving to a more sustainablemodel most activities around the worldcontinue to be run lsquolsquobusiness as usualrsquorsquo
ignoring even the consensual IPCC assess-ments A minimum of caution calls forhuman society to consider also scenariosresulting from scientific knowledge butthat have not gained consensus It isimpossible to adapt to any one of theworst possibilities or even to many ofthem but we must strongly recommendthat apart from using consensual scientificknowledge for most initiatives we takeinto account nonlineal steep catastrophicpossibilities and while doing that wedevelop a reaction system to face unex-pected fast changes mobilizing peopleand resources to fight these kind of events
The United Nations has already creat-ed the Hyogo Framework a plan of actionto advise policymakers of the differentcountries on reducing our collective vul-nerability to natural hazards and theGlobal Platform for Disaster Risk Reduc-tion in order to increase the commitmentof nations by advising them on ways tostrengthen public infrastructures coastalfacilities and homes to withstand moreextreme weather flooding and risingwaters and to develop better droughtmanagement better early warning systemsand evacuation plans stronger buildingcodes improved land and water manage-ment policies expanded disaster educationprograms for local communities etc Allof this should be backed by strongerinstitutions and proper funding even fromthe economic point of view A recentexpert study in the United States showsthat one dollar invested today in disasterrisk reduction saves four dollars in thefuture cost of relief and rehabilitationmdashabargain by any standard (J Holmes 2007First Session of the Global Platform forDisaster Risk Reduction) However na-tional commitments will be slow andmany countries do not have the means tofollow these recommendations Mean-while we need a UN environmentalemergency force including resources (peo-ple equipment money) for medical assis-tance and for fighting fire floods severedroughts and other hazards
A continuous multiscale multifactorialmonitoring of the Earth system is vital tokeep an eye on these not-yet-consensualpossible environmental changes and arenovated United Nations economic andpolitical effort is necessary to develop sucha reaction system These are two impor-tant challenges for science and society inthis emerging twenty-first century We callhere for their consideration After all thisis what is done in many other smaller-scale
Ambio Vol 37 No 4 June 2008 321 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
anthropic processes just consider thesecurity levels and reaction systems withwhich we build our bridges or our housesin earthquake prone areas Earth is now aclimate-quake prone area for us and manypeople are unable to defend themselvessinglehandedly
References and Notes
1 Intergovernmental Panel on Climate Change 2007Climate Change 2007 Synthesis Report Summary forP o l i c y m a k e r s ( h t t p www i p c c c h p d f assessment-reportar4ar4_syr_spmpdf)
2 Canadell JG Le Quere C Raupach MR FieldCB Bultenhuis ET Ciais Ph Conwayu TJGillett NP et al 2007 Contributions to acceleratingatmospheric CO2 growth from economic activity carbonintensity and efficiency of natural sinks Proc NatAcad Sci USA 104 18866ndash18870
3 Kerr RA 2007 Is battered Arctic Sea ice down for thecount Science 318 33ndash34
4 Overpeck JT Otto-Blesner BL Milner GH MohsDR Alley RB and Kiehl JT 2006 Paleoclimaticevidence for future ice-sheet instability and rapid sea-level rise Science 311 1747ndash1750
Jaume TerradasCenter for Ecological Research andForestry ApplicationsmdashDepartmentof Animal Biology Plant Biologyand Ecology
Edifici CUniversitat Autonoma de Barcelona08913 Bellaterra
Spainjaumeterradasuabcat
Josep PenuelasCenter for Ecological Research andForestry ApplicationmdashNationalResearch Council of Spain
Edifici CUniversitat Autonoma de Barcelona08913 BellaterraSpainjoseppenuelasuabcat
Synopsis
This synopsis was not peer reviewed
Grassland Classification in Naqu Prefectureof Tibet
Naqu Prefecture is a part of Tibet andcovers a vast territory with an averagealtitude of 4500 m (Fig 1) It is one of themost important centers for animal pro-duction in Tibet and carries about 692million head of various livestock on about286 900 km2 of native grasslands Yak andsheep are well adapted to the localenvironment and account for 40 and31 of livestock population in Tibetrespectively (1) However animal hus-bandry in Naqu prefecture has facedsevere development problems due to thecombined effects of grassland degradationlong cold seasons and economic con-straints including distance from marketcenters inadequate infrastructure anduncertain grassland tenure arrangements(2) To resolve some of these problemsfacing herdsmen and regional planners ajoint research effort by Naqu AnimalHusbandry Bureau and Gansu GrasslandEcological Research Institute (GGERI)was initiated in 1990 to improve produc-tion of grassland and livestock (3) Thispaper focuses on the results of a grasslandclassification survey that included anevaluation of grazing capacity and com-ments on relevant policy implications Theresearch approach adopted was a combi-nation of remote sensing technologies andtraditional field survey methods
Remote sensing technology was com-bined with field survey as the researchapproach used to overcome the problemsof the vast area and terrain diversity inNaqu The grassland classification wasmade using the results of interpretations
of Landsat images and field survey Itfollowed the procedures used in the ChinaGrassland Classification System that weredeveloped from a grassland classificationsystem used in the former Soviet Unionand modified for Chinese conditions (4 5)According to this system that is promul-gated by the Ministry of Agriculture (6)the grassland is classified in terms of zonalclimatic features degree of use by live-stock and characteristics of plant com-
munity There are three levels ofclassification units in this system The firstlevel (called lsquolsquoclassrsquorsquo) incorporates grass-lands with similar macrotopographicalcondition and landscape into one typethat mainly reflects the feature of aclimatic zone eg temperature and mois-ture Classes are subdivided at a secondarylevel into lsquolsquogroupsrsquorsquo according to theforaging attributes of plants for livestockuse and variation of mesotopography and
Figure 1 Naqu location map
322 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
soil The third classification unit (calledlsquolsquotypersquorsquo) divides groups with grasslanddensity based on dominant plant specieswithin the grass community
Grassland Classification
The native grasslands of Naqu Prefecturewere subdivided into 4 classes 10 groupsand 32 types The distribution of grasslandclasses was identical to the geographic-climatic zones and included bush meadowalpine meadow alpine steppe and desertsteppe which form a horizontal-zonalpattern
Bush Meadow
The bush meadow class is distributedmainly over the hilly areas in the easterncounties of Naqu (eg Jiali SuoxianBiru and Baqing) where the climate iswet and comparatively temperate Theannual precipitation ranges from 579 mmto 650 mm with 80 occurring in thegrowing season (200ndash224 d) Averageannual temperature ranges from 158C to358C Owing to the diversified ecologicalconditions caused by topographic varia-tion the farming systems are mixed withlarge areas of native pasture in the lowlandand river valleys already converted tograin and cash crops Wheat peas rapepotato millet corn and buckwheat aremajor crops in these counties as well astraditional highland barley Yak andTibetan sheep are the major grazinglivestock with yaks accounting for 40of the prefecture livestock because they areso well adapted to the wet climate andhighland conditions Cattle and horses arealso important although cattle are mainlykept for use as draft animals for cropcultivation The emergence of the mixedfarming systems has led to peasantsbecoming settled in villages which in turnhas resulted in the development of animalhusbandry methods that differ significant-ly from the traditional nomadism in thepure pastoral areas The use of lowlandsand river valleys for crop production hasshifted livestock grazing to the hilly areasAlthough the grasslands are abundantprecipitous terrain and forestry landsrestrict grazing activities to certain alti-tudes (between 4200 and 4600 m) andplaces with relatively gentle slopes (258)Grasslands with these features account for8 of total usable grassland area in theprefecture Within this restricted usablegrassland area one typical group grami-neae is identified On the north-facingslopes between 4300 and 4600 m Rhodo-dendron nivale Hook f are dominant inassociation with Sibiraea angustata Hand-Mazz Spiraea alpina Pall and Potentillafruticosa L which are often used by yakand cattle Above 4700 m herbs graduallyreplace the dominant bushes On thesouth-facing slopes between 4200 and4500 m Elymus nutans Griseb Festuca
ovina L and Poa annua L are dominantin association with Kobresia pygmaeaKobresia humilis and Sabina tibeticaKom Because of the high foraging valueof these herbs and the relatively warmconditions yaks sheep cattle and horsesare intensively grazed on the south-facingslopes in the summer periods causingsevere overgrazing In winter livestockare grazed near the villages on thescattered grassland in the valleys andlowlands and supplemented with cropresidues and hays
Alpine Meadow
Alpine meadow is distributed over theriver terraces valleys and alluvial fans inthe west parts of the four eastern countieslarge areas of Naqu and Nierong and partof Anduo County It is the major grass-land class for livestock production in theprefecture accounting for 43 of the totalusable grassland area Cyperaceae formthe most abundant and forageable groupwhich accounts for 73 of the grasslandarea in this class Four grassland groupswere identified in this class based on theforaging values of plants and the meso-topography This vegetation is widelydistributed over flatter highlands valleysand sunny sides of hills over an altituderange between 4000 and 5200 m in the eastand central parts (eg Biru Suoxian JaliBaqing Naqu Nierong and Ando) Theclimate is suitable for this grassland groupthat prefers cold and wet climatic condi-tions with a protracted cold season as longas 8 mo and average rainfall of 400 mmThe K pygmaea grassland is the majortype and provides the best summer andautumn grazing for sheep and yaks in theprefecture as a result of its high foragingvalue and flatter terrain Although thecomposition of the grassland is relativelycomplex K pygmaea generally dominatesthe community with Sarracenia purpureaPoligonum macrophyllum D Don and Enutans present as subdominants Somehigher producing Kobresia grasslands arecut for hay production Overgrazingdrought and rodents are thought to beresponsible for the severe degradation ofthis grassland type
The gramineae form the next importantgrassland group in the class of alpinemeadow Kobresia pygmaea has a strongecological adaptation that enables it todominate plant communities above 5300m with cushion plants as a subdominantThis vegetation is mainly distributed in thetransition zones between alpine meadowand steppe classes and located in thevalley lake basin and saline meadowsbetween 4500 and 5200 m Three types ofgrassland within this group were identifiedbased on the dominant species whichincluded E nutans Achnatherum hookeriKeng and Puccinella himalaica Tzvel
Evergreen shrubs are the third group inthe alpine meadow that is located on the
north-facing sides of hills with altitudebetween 4200 and 4600 m in the easterncounties These types of grassland usuallyprovide winter and spring grazing forlivestock
Deciduous shrubs are the last group ofalpine meadow Rhododendron nivale dom-inate this group and the areas with lesscanopy density are usually used forgrazing yak and cattle in the warm seasonThis group is mainly distributed on north-facing hills with altitude between 4600 and4900 m in Naqu Suoxian Biru Jiali andBaqing It is also distributed on the south-facing sides of hills at 4000 and 4500 mwith P fruticosa and Elsholtzia fruticosaKehd as the dominant species Cutting byfarmers for household fuel for a longperiod of time has reduced canopy densityover large areas that are now used asgrazing lands for sheep yak and cattleThe areas with altitude of 4600 to 4900 mare usually used as grazing in the warmseason and the grasslands below thesealtitudes are used in the cold season
Alpine Steppe
Alpine steppe accounts for 57 of thetotal grassland areas in the prefecture andis an important area of sheep and goatproduction It is mainly distributed in thecentral and west counties of WenbuShuanghu Shengzha Bange and Anduowhere the altitude ranges between 4400and 5000 m and the climate is cold dryand windy The annual rainfall increasesfrom 100 mm to 300 mm from west to eastPlant composition in this class is generallyless botanically complex than alpine mead-ow with only 5 to 15 species Gramineaeform a typical group in this class whichoccurs in the valleys river terraces lakebasins alluvial fans and lake plains to thesouthwest of Naqu Prefecture A repre-sentative species in this group is Spurpurea Cyperaceae dominated byCarex moorcroftii is usually distributednorthwest of Naqu prefecture Deciduoustrees and shrubs normally distributed inthe flood land and shady sides of the hillsare also used by livestock
Desert Steppe
Desert steppe is widely distributed in thesandy land of lake basins alluvial fansand slopes of hills between Kekexili andKunlun Mountains where the averagealtitude exceeds 5000 m and the climateis extremely cold and dry Annual rainfallaverages only 100 mm Grassland compo-sition is very simple and only includesthree to five species of which Carexcompacta with C moorcroftii and Spurpurea occur frequently Desert steppeareas are lsquolsquounpopulated areasrsquorsquo wherewildlife such as wild yak Tibetan wilddonkey Tibetan antelope wolf fox etcmay be found
Ambio Vol 37 No 4 June 2008 323 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
References and Notes
1 Statistical Bureau of Tibet 2005 Annual EconomicStatistical Data of Tibet Lasa Tibet Press (In Chinese)
2 Liu J Zhan J and Deng X 2005 Spatio-temporalpatterns and driving forces of urban land expansion inChina during the economic reform era Ambio 34 450ndash455
3 Gansu Grassland Ecological Research Institute 1991Grassland and Livestock Resources in Naqu Prefecture ofTibet Lanzhou Gansu Science and Technology Press(In Chinese)
5 Peng X 1985 The rules and systems of grasslandclassification in China Sichuan Grassland 2 13ndash15 (InChinese)
6 Zizhi H 1996 Introduction to Grassland ClassificationBeijing Agricultural Press (In Chinese)
7 This work has been supported by Chinarsquos Special Fundfor Major State Basic Research Project (2007CB714406)Knowledge Innovation Program of the Chinese Acade-my of Sciences (approved KZCX2-YW-313 and
KZCX1-Y-02) foundation of the Chinese State KeyLaboratory of Remote Sensing Science (KQ060006)
Wang LiwenThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 Chinawlw9585163com
Wei YaxingDepartment of Geography LiaoningNormal University Dalian 116029China
Niu ZhengThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 China
Synopsis
This synopsis was not peer reviewed
The Contribution of Ironstone Outcropsto Plant Diversity in the Iron Quadranglea Threatened Brazilian Landscape
INTRODUCTION
Due to the contribution of a hithertoneglected ecosystem one of the richestmineral provinces in the world at theheart of a center of floristic diversity mayprove much more diverse and vulnerablethan the current figures show
The Iron Quadrangle (local nameQuadrilatero Ferrıfero) located in south-east Brazil covers an area of approximate-ly 7200 km2 and represents one of the mostimportant and well-studied geological siteson the planet It is contained entirelywithin the wealthy state of Minas Geraisthe area of which is approximately 587 000km2 larger than France The Portuguesename lsquolsquogeneral minesrsquorsquo attests to thehistorical ties of this state with the miningindustry since colonial times Constitutedby very oldmdashArchean and Paleoprotero-zoicmdashterrains the Iron Quadrangle land-scape is presently a mosaic at the ecotoneof two Brazilian hotspots Cerrado andAtlantic Forest which have been pro-foundly transformed by human activitiesnamely urbanization and mining
The region is one of the leadingproducers of metallic minerals in theworld especially superficial iron ore Theintense mining activity entails a completealteration of the landscape with enormousimpacts on the local and regional biodi-versity The superficial iron crusts locallyknown as canga are the result of weath-
ering of minerals derived from banded-iron formations (BIFs) compact hematiteand limonite (1) and they are distributedon the tops and sides of some mountainsformed by the huge deposits of iron orethat set the limits of the Iron QuadrangleThese outcrops form islands on top of hillsat altitudes ranging from 1000 to2000 m
Currently there are about 50 iron-oreopencast mines the extents of which mayreach 2000 ha Opencast mining is highlyaggressive to the environment because theironstone outcrops and their associatedbiota are discarded so that the iron-oredeposits can be reached and the excava-tions can reach 300 m depth and exposethe water table Furthermore the wastederived from these activities contaminates
nearby watersheds with heavy metals andtoxic elements (2)
These outcrops harbor characteristicrupestral vegetation which is shrub-dom-inated together with a large number ofsedges grasses and orchids most of whichare epilithic Due to their very restrictedarea difficult access and because they areassociated with high-quality iron-ore de-posits the plant communities over cangaare among the most threatened and leaststudied in the otherwise thoroughly sur-veyed ecosystems of southeast BrazilUntil recently rupestral plant communi-ties in the region had been given nodifferentiation with respect to the type ofsubstrate that harbored them Henceplants growing over iron ore were fre-quently recorded together with those
General landscape of the Iron Quadrangleviewed from an ironstone outcrop
Partial view of an opencast iron-ore mineshowing the superficial crust removal
324 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
growing over sandstone or granite Thehistorical lack of differentiation amonglithologies has prevented us from fullycomprehending the role of the flora andfauna biodiversity associated with theseironstone outcrops Recent studies how-ever have begun to reveal that the plantcommunities over ironstone outcropswhich are almost exclusively found in theIron Quadrangle with exception of Car-ajas in north Brazil (equally threatened byiron-ore mining) have a floristic identityand an extremely high local and regionaldiversity that equals or surpasses those ofthe other two lithologies
Preliminary comparative surveysamong the two major outcrop types inthe Iron Quadrangle sandstone and iron-stone suggest that the plant communitiesestablished over the latter contribute moreheavily to the biodiversity of the regionthan had been previously imagined Inonly six ironstones outcrops recentlysurveyed which together barely reach100 ha 430 angiosperm species distributedamong 78 families were catalogued Thisnumber represents 36 of all the familiesin Brazil the country with the highestplant diversity Notably some of thesespecies are endemic to very few outcropswithin the Iron Quadrangle such as themilkweed Ditassa monocoronata and thecactus Arthrocereus glaziovii These sur-veys illustrate the need to acceleratestudies of this particular environmentwhich in contrast to the well-documentedand world-known sandstone outcrops (thepredominant rock type in the area) isundergoing increasing economic pressure
WHY RESEARCH IRONSTONEOUTCROPS
The Iron Quadrangle makes up thesouthern end of an orographic groupknown as Espinhaco Range which isrecognized as one of the regions withhighest floristic diversity in South Amer-ica having more than 30 endemicspecies most of which are associated withrock outcrop environments (3) Theseamong other peculiarities recently grantedthe Espinhaco Range the status of Bio-sphere Reserve by the United NationsEducational Scientific and Cultural Orga-nization
Following this lead and with the aim ofestablishing their identity an ongoingproject at the Federal University of MinasGerais is devoted to determining thecontribution of the flora on ironstoneoutcrops to the regional plant diversityand to ascertaining the conservation statusof these ecosystems throughout the IronQuadrangle The initiative which com-bines botanists and ecologists has alreadyrevealed a very high local diversity show-ing astonishing numbers such as 16species of vascular plants in a single squaremeter This variety is the result of the smallsize of plants the rich matrix in which theyare embedded and the mineral andtopographical heterogeneity of these out-crops which create distinct microhabitatsside by side and result in a uniqueassociation of plants (4) Aside from themore typical communities that are alsocommon to other lithologies virtuallynothing is known about two plant com-munities typical of ironstone outcropstemporal ponds and penumbral rockcommunities associated with cliffs andcave entrances
The high diversity contrasts with thesevere edapho-climatic conditions typicalof outcrops in general such as highultraviolet (UV) intensities daily thermalsubstrate variations that can reach 458Crapid water loss and poorly developed soilcover which in the case of ironstones arefurther aggravated by a high content ofheavy metals One of the most relevantplant communities for conservation inregions with intense mining activities aremetallophyle plants which encompassthose species that have mechanisms ofresistance tolerance or bioaccumulationregarding metals usually taxa that areendemic to metalliferous areas Thesecommunities are being investigated forecological services such as phytoextrac-tion phytostabilization and phytopro-spection At present several researchgroups are focusing on the conservationand sustainable use of these communitiesfollowing the recommendations of theConvention on Biological Diversity toidentify and conserve metallophyles Theserecommendations have even been pro-posed for inclusion in the EnvironmentalManagement System ISO 14 000 (5) Thisproposal is fundamental to the short-termconservation of plant communities onironstone outcrops because to date thereis no specific environmental legislationthat protects this ecosystem In Brazilthere are important regions with rockoutcrops rich in metals like the Iron
Quadrangle itself However metallophylecommunities in spite of their evidentenvironmental importance have yet tobecome the focus of attention
Aside from the applications for sus-tainable use or for recovery of areasdegraded by mining the isolation amongoutcrops and plant and physiologicaladaptations make these environments amodel system for fundamental ecologicaland evolutionary questions such as pat-terns of species richness and distributionof species
BIODIVERSITY LOSS AND CON-SERVATION STATUS
Habitat loss and alteration have long beenrecognized as leading threats to worldbiodiversity In Brazilian ironstone out-crops this process occurs basically inassociation with mining activities Recent-ly this historical regional vocation hasbeen heavily accelerated as a consequenceof the economic emergence of Chinawhich has generated unprecedented de-mand for raw materials worldwide inparticular high-quality iron ore a phe-nomenon that has been termed lsquolsquothe Chinaeffectrsquorsquo in the commodities jargon Miningactivities contribute heavily to the Brazil-ian gross domestic product (GDP) In2000 the iron ore produced in the regionaccounted for 12 of the total value ofBrazilian mineral production excludingthe fossil fuels petroleum and gas (6)
Most floristic surveys of ironstoneoutcrops in the Iron Quadrangle are veryrecent Of the handful outcrops surveyedonly one is located within a conservationunit The others are located in areas ownedby mining companies which unfortunatelyreflects the vulnerable status of thisecosystem The mineral rights granted toindustry until 2002 cover an area of207 000 ha of the Iron Quadrangle Thisrepresents roughly 28 of the total IronQuadrangle area and probably 90 of allironstone outcrops in the region andillustrates that iron-ore exploitation over-laps heavily with these environments
Currently there are nine national parksin southeast Brazil that contain rockoutcrops and these are distributedthroughout extensive mountain rangessuch as the Mantiqueira and Serra doMar (granite outcrops) and Canastra andEspinhaco (sandstone outcrops) whichtogether cover 679 000 ha In the stateof Minas Gerais alone there are 14 stateparks that together cover around 212 000
Table 1 Public conservation units in southeast Brazil containing rock outcrops
Ambio Vol 37 No 4 June 2008 325 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
anthropic processes just consider thesecurity levels and reaction systems withwhich we build our bridges or our housesin earthquake prone areas Earth is now aclimate-quake prone area for us and manypeople are unable to defend themselvessinglehandedly
References and Notes
1 Intergovernmental Panel on Climate Change 2007Climate Change 2007 Synthesis Report Summary forP o l i c y m a k e r s ( h t t p www i p c c c h p d f assessment-reportar4ar4_syr_spmpdf)
2 Canadell JG Le Quere C Raupach MR FieldCB Bultenhuis ET Ciais Ph Conwayu TJGillett NP et al 2007 Contributions to acceleratingatmospheric CO2 growth from economic activity carbonintensity and efficiency of natural sinks Proc NatAcad Sci USA 104 18866ndash18870
3 Kerr RA 2007 Is battered Arctic Sea ice down for thecount Science 318 33ndash34
4 Overpeck JT Otto-Blesner BL Milner GH MohsDR Alley RB and Kiehl JT 2006 Paleoclimaticevidence for future ice-sheet instability and rapid sea-level rise Science 311 1747ndash1750
Jaume TerradasCenter for Ecological Research andForestry ApplicationsmdashDepartmentof Animal Biology Plant Biologyand Ecology
Edifici CUniversitat Autonoma de Barcelona08913 Bellaterra
Spainjaumeterradasuabcat
Josep PenuelasCenter for Ecological Research andForestry ApplicationmdashNationalResearch Council of Spain
Edifici CUniversitat Autonoma de Barcelona08913 BellaterraSpainjoseppenuelasuabcat
Synopsis
This synopsis was not peer reviewed
Grassland Classification in Naqu Prefectureof Tibet
Naqu Prefecture is a part of Tibet andcovers a vast territory with an averagealtitude of 4500 m (Fig 1) It is one of themost important centers for animal pro-duction in Tibet and carries about 692million head of various livestock on about286 900 km2 of native grasslands Yak andsheep are well adapted to the localenvironment and account for 40 and31 of livestock population in Tibetrespectively (1) However animal hus-bandry in Naqu prefecture has facedsevere development problems due to thecombined effects of grassland degradationlong cold seasons and economic con-straints including distance from marketcenters inadequate infrastructure anduncertain grassland tenure arrangements(2) To resolve some of these problemsfacing herdsmen and regional planners ajoint research effort by Naqu AnimalHusbandry Bureau and Gansu GrasslandEcological Research Institute (GGERI)was initiated in 1990 to improve produc-tion of grassland and livestock (3) Thispaper focuses on the results of a grasslandclassification survey that included anevaluation of grazing capacity and com-ments on relevant policy implications Theresearch approach adopted was a combi-nation of remote sensing technologies andtraditional field survey methods
Remote sensing technology was com-bined with field survey as the researchapproach used to overcome the problemsof the vast area and terrain diversity inNaqu The grassland classification wasmade using the results of interpretations
of Landsat images and field survey Itfollowed the procedures used in the ChinaGrassland Classification System that weredeveloped from a grassland classificationsystem used in the former Soviet Unionand modified for Chinese conditions (4 5)According to this system that is promul-gated by the Ministry of Agriculture (6)the grassland is classified in terms of zonalclimatic features degree of use by live-stock and characteristics of plant com-
munity There are three levels ofclassification units in this system The firstlevel (called lsquolsquoclassrsquorsquo) incorporates grass-lands with similar macrotopographicalcondition and landscape into one typethat mainly reflects the feature of aclimatic zone eg temperature and mois-ture Classes are subdivided at a secondarylevel into lsquolsquogroupsrsquorsquo according to theforaging attributes of plants for livestockuse and variation of mesotopography and
Figure 1 Naqu location map
322 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
soil The third classification unit (calledlsquolsquotypersquorsquo) divides groups with grasslanddensity based on dominant plant specieswithin the grass community
Grassland Classification
The native grasslands of Naqu Prefecturewere subdivided into 4 classes 10 groupsand 32 types The distribution of grasslandclasses was identical to the geographic-climatic zones and included bush meadowalpine meadow alpine steppe and desertsteppe which form a horizontal-zonalpattern
Bush Meadow
The bush meadow class is distributedmainly over the hilly areas in the easterncounties of Naqu (eg Jiali SuoxianBiru and Baqing) where the climate iswet and comparatively temperate Theannual precipitation ranges from 579 mmto 650 mm with 80 occurring in thegrowing season (200ndash224 d) Averageannual temperature ranges from 158C to358C Owing to the diversified ecologicalconditions caused by topographic varia-tion the farming systems are mixed withlarge areas of native pasture in the lowlandand river valleys already converted tograin and cash crops Wheat peas rapepotato millet corn and buckwheat aremajor crops in these counties as well astraditional highland barley Yak andTibetan sheep are the major grazinglivestock with yaks accounting for 40of the prefecture livestock because they areso well adapted to the wet climate andhighland conditions Cattle and horses arealso important although cattle are mainlykept for use as draft animals for cropcultivation The emergence of the mixedfarming systems has led to peasantsbecoming settled in villages which in turnhas resulted in the development of animalhusbandry methods that differ significant-ly from the traditional nomadism in thepure pastoral areas The use of lowlandsand river valleys for crop production hasshifted livestock grazing to the hilly areasAlthough the grasslands are abundantprecipitous terrain and forestry landsrestrict grazing activities to certain alti-tudes (between 4200 and 4600 m) andplaces with relatively gentle slopes (258)Grasslands with these features account for8 of total usable grassland area in theprefecture Within this restricted usablegrassland area one typical group grami-neae is identified On the north-facingslopes between 4300 and 4600 m Rhodo-dendron nivale Hook f are dominant inassociation with Sibiraea angustata Hand-Mazz Spiraea alpina Pall and Potentillafruticosa L which are often used by yakand cattle Above 4700 m herbs graduallyreplace the dominant bushes On thesouth-facing slopes between 4200 and4500 m Elymus nutans Griseb Festuca
ovina L and Poa annua L are dominantin association with Kobresia pygmaeaKobresia humilis and Sabina tibeticaKom Because of the high foraging valueof these herbs and the relatively warmconditions yaks sheep cattle and horsesare intensively grazed on the south-facingslopes in the summer periods causingsevere overgrazing In winter livestockare grazed near the villages on thescattered grassland in the valleys andlowlands and supplemented with cropresidues and hays
Alpine Meadow
Alpine meadow is distributed over theriver terraces valleys and alluvial fans inthe west parts of the four eastern countieslarge areas of Naqu and Nierong and partof Anduo County It is the major grass-land class for livestock production in theprefecture accounting for 43 of the totalusable grassland area Cyperaceae formthe most abundant and forageable groupwhich accounts for 73 of the grasslandarea in this class Four grassland groupswere identified in this class based on theforaging values of plants and the meso-topography This vegetation is widelydistributed over flatter highlands valleysand sunny sides of hills over an altituderange between 4000 and 5200 m in the eastand central parts (eg Biru Suoxian JaliBaqing Naqu Nierong and Ando) Theclimate is suitable for this grassland groupthat prefers cold and wet climatic condi-tions with a protracted cold season as longas 8 mo and average rainfall of 400 mmThe K pygmaea grassland is the majortype and provides the best summer andautumn grazing for sheep and yaks in theprefecture as a result of its high foragingvalue and flatter terrain Although thecomposition of the grassland is relativelycomplex K pygmaea generally dominatesthe community with Sarracenia purpureaPoligonum macrophyllum D Don and Enutans present as subdominants Somehigher producing Kobresia grasslands arecut for hay production Overgrazingdrought and rodents are thought to beresponsible for the severe degradation ofthis grassland type
The gramineae form the next importantgrassland group in the class of alpinemeadow Kobresia pygmaea has a strongecological adaptation that enables it todominate plant communities above 5300m with cushion plants as a subdominantThis vegetation is mainly distributed in thetransition zones between alpine meadowand steppe classes and located in thevalley lake basin and saline meadowsbetween 4500 and 5200 m Three types ofgrassland within this group were identifiedbased on the dominant species whichincluded E nutans Achnatherum hookeriKeng and Puccinella himalaica Tzvel
Evergreen shrubs are the third group inthe alpine meadow that is located on the
north-facing sides of hills with altitudebetween 4200 and 4600 m in the easterncounties These types of grassland usuallyprovide winter and spring grazing forlivestock
Deciduous shrubs are the last group ofalpine meadow Rhododendron nivale dom-inate this group and the areas with lesscanopy density are usually used forgrazing yak and cattle in the warm seasonThis group is mainly distributed on north-facing hills with altitude between 4600 and4900 m in Naqu Suoxian Biru Jiali andBaqing It is also distributed on the south-facing sides of hills at 4000 and 4500 mwith P fruticosa and Elsholtzia fruticosaKehd as the dominant species Cutting byfarmers for household fuel for a longperiod of time has reduced canopy densityover large areas that are now used asgrazing lands for sheep yak and cattleThe areas with altitude of 4600 to 4900 mare usually used as grazing in the warmseason and the grasslands below thesealtitudes are used in the cold season
Alpine Steppe
Alpine steppe accounts for 57 of thetotal grassland areas in the prefecture andis an important area of sheep and goatproduction It is mainly distributed in thecentral and west counties of WenbuShuanghu Shengzha Bange and Anduowhere the altitude ranges between 4400and 5000 m and the climate is cold dryand windy The annual rainfall increasesfrom 100 mm to 300 mm from west to eastPlant composition in this class is generallyless botanically complex than alpine mead-ow with only 5 to 15 species Gramineaeform a typical group in this class whichoccurs in the valleys river terraces lakebasins alluvial fans and lake plains to thesouthwest of Naqu Prefecture A repre-sentative species in this group is Spurpurea Cyperaceae dominated byCarex moorcroftii is usually distributednorthwest of Naqu prefecture Deciduoustrees and shrubs normally distributed inthe flood land and shady sides of the hillsare also used by livestock
Desert Steppe
Desert steppe is widely distributed in thesandy land of lake basins alluvial fansand slopes of hills between Kekexili andKunlun Mountains where the averagealtitude exceeds 5000 m and the climateis extremely cold and dry Annual rainfallaverages only 100 mm Grassland compo-sition is very simple and only includesthree to five species of which Carexcompacta with C moorcroftii and Spurpurea occur frequently Desert steppeareas are lsquolsquounpopulated areasrsquorsquo wherewildlife such as wild yak Tibetan wilddonkey Tibetan antelope wolf fox etcmay be found
Ambio Vol 37 No 4 June 2008 323 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
References and Notes
1 Statistical Bureau of Tibet 2005 Annual EconomicStatistical Data of Tibet Lasa Tibet Press (In Chinese)
2 Liu J Zhan J and Deng X 2005 Spatio-temporalpatterns and driving forces of urban land expansion inChina during the economic reform era Ambio 34 450ndash455
3 Gansu Grassland Ecological Research Institute 1991Grassland and Livestock Resources in Naqu Prefecture ofTibet Lanzhou Gansu Science and Technology Press(In Chinese)
5 Peng X 1985 The rules and systems of grasslandclassification in China Sichuan Grassland 2 13ndash15 (InChinese)
6 Zizhi H 1996 Introduction to Grassland ClassificationBeijing Agricultural Press (In Chinese)
7 This work has been supported by Chinarsquos Special Fundfor Major State Basic Research Project (2007CB714406)Knowledge Innovation Program of the Chinese Acade-my of Sciences (approved KZCX2-YW-313 and
KZCX1-Y-02) foundation of the Chinese State KeyLaboratory of Remote Sensing Science (KQ060006)
Wang LiwenThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 Chinawlw9585163com
Wei YaxingDepartment of Geography LiaoningNormal University Dalian 116029China
Niu ZhengThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 China
Synopsis
This synopsis was not peer reviewed
The Contribution of Ironstone Outcropsto Plant Diversity in the Iron Quadranglea Threatened Brazilian Landscape
INTRODUCTION
Due to the contribution of a hithertoneglected ecosystem one of the richestmineral provinces in the world at theheart of a center of floristic diversity mayprove much more diverse and vulnerablethan the current figures show
The Iron Quadrangle (local nameQuadrilatero Ferrıfero) located in south-east Brazil covers an area of approximate-ly 7200 km2 and represents one of the mostimportant and well-studied geological siteson the planet It is contained entirelywithin the wealthy state of Minas Geraisthe area of which is approximately 587 000km2 larger than France The Portuguesename lsquolsquogeneral minesrsquorsquo attests to thehistorical ties of this state with the miningindustry since colonial times Constitutedby very oldmdashArchean and Paleoprotero-zoicmdashterrains the Iron Quadrangle land-scape is presently a mosaic at the ecotoneof two Brazilian hotspots Cerrado andAtlantic Forest which have been pro-foundly transformed by human activitiesnamely urbanization and mining
The region is one of the leadingproducers of metallic minerals in theworld especially superficial iron ore Theintense mining activity entails a completealteration of the landscape with enormousimpacts on the local and regional biodi-versity The superficial iron crusts locallyknown as canga are the result of weath-
ering of minerals derived from banded-iron formations (BIFs) compact hematiteand limonite (1) and they are distributedon the tops and sides of some mountainsformed by the huge deposits of iron orethat set the limits of the Iron QuadrangleThese outcrops form islands on top of hillsat altitudes ranging from 1000 to2000 m
Currently there are about 50 iron-oreopencast mines the extents of which mayreach 2000 ha Opencast mining is highlyaggressive to the environment because theironstone outcrops and their associatedbiota are discarded so that the iron-oredeposits can be reached and the excava-tions can reach 300 m depth and exposethe water table Furthermore the wastederived from these activities contaminates
nearby watersheds with heavy metals andtoxic elements (2)
These outcrops harbor characteristicrupestral vegetation which is shrub-dom-inated together with a large number ofsedges grasses and orchids most of whichare epilithic Due to their very restrictedarea difficult access and because they areassociated with high-quality iron-ore de-posits the plant communities over cangaare among the most threatened and leaststudied in the otherwise thoroughly sur-veyed ecosystems of southeast BrazilUntil recently rupestral plant communi-ties in the region had been given nodifferentiation with respect to the type ofsubstrate that harbored them Henceplants growing over iron ore were fre-quently recorded together with those
General landscape of the Iron Quadrangleviewed from an ironstone outcrop
Partial view of an opencast iron-ore mineshowing the superficial crust removal
324 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
growing over sandstone or granite Thehistorical lack of differentiation amonglithologies has prevented us from fullycomprehending the role of the flora andfauna biodiversity associated with theseironstone outcrops Recent studies how-ever have begun to reveal that the plantcommunities over ironstone outcropswhich are almost exclusively found in theIron Quadrangle with exception of Car-ajas in north Brazil (equally threatened byiron-ore mining) have a floristic identityand an extremely high local and regionaldiversity that equals or surpasses those ofthe other two lithologies
Preliminary comparative surveysamong the two major outcrop types inthe Iron Quadrangle sandstone and iron-stone suggest that the plant communitiesestablished over the latter contribute moreheavily to the biodiversity of the regionthan had been previously imagined Inonly six ironstones outcrops recentlysurveyed which together barely reach100 ha 430 angiosperm species distributedamong 78 families were catalogued Thisnumber represents 36 of all the familiesin Brazil the country with the highestplant diversity Notably some of thesespecies are endemic to very few outcropswithin the Iron Quadrangle such as themilkweed Ditassa monocoronata and thecactus Arthrocereus glaziovii These sur-veys illustrate the need to acceleratestudies of this particular environmentwhich in contrast to the well-documentedand world-known sandstone outcrops (thepredominant rock type in the area) isundergoing increasing economic pressure
WHY RESEARCH IRONSTONEOUTCROPS
The Iron Quadrangle makes up thesouthern end of an orographic groupknown as Espinhaco Range which isrecognized as one of the regions withhighest floristic diversity in South Amer-ica having more than 30 endemicspecies most of which are associated withrock outcrop environments (3) Theseamong other peculiarities recently grantedthe Espinhaco Range the status of Bio-sphere Reserve by the United NationsEducational Scientific and Cultural Orga-nization
Following this lead and with the aim ofestablishing their identity an ongoingproject at the Federal University of MinasGerais is devoted to determining thecontribution of the flora on ironstoneoutcrops to the regional plant diversityand to ascertaining the conservation statusof these ecosystems throughout the IronQuadrangle The initiative which com-bines botanists and ecologists has alreadyrevealed a very high local diversity show-ing astonishing numbers such as 16species of vascular plants in a single squaremeter This variety is the result of the smallsize of plants the rich matrix in which theyare embedded and the mineral andtopographical heterogeneity of these out-crops which create distinct microhabitatsside by side and result in a uniqueassociation of plants (4) Aside from themore typical communities that are alsocommon to other lithologies virtuallynothing is known about two plant com-munities typical of ironstone outcropstemporal ponds and penumbral rockcommunities associated with cliffs andcave entrances
The high diversity contrasts with thesevere edapho-climatic conditions typicalof outcrops in general such as highultraviolet (UV) intensities daily thermalsubstrate variations that can reach 458Crapid water loss and poorly developed soilcover which in the case of ironstones arefurther aggravated by a high content ofheavy metals One of the most relevantplant communities for conservation inregions with intense mining activities aremetallophyle plants which encompassthose species that have mechanisms ofresistance tolerance or bioaccumulationregarding metals usually taxa that areendemic to metalliferous areas Thesecommunities are being investigated forecological services such as phytoextrac-tion phytostabilization and phytopro-spection At present several researchgroups are focusing on the conservationand sustainable use of these communitiesfollowing the recommendations of theConvention on Biological Diversity toidentify and conserve metallophyles Theserecommendations have even been pro-posed for inclusion in the EnvironmentalManagement System ISO 14 000 (5) Thisproposal is fundamental to the short-termconservation of plant communities onironstone outcrops because to date thereis no specific environmental legislationthat protects this ecosystem In Brazilthere are important regions with rockoutcrops rich in metals like the Iron
Quadrangle itself However metallophylecommunities in spite of their evidentenvironmental importance have yet tobecome the focus of attention
Aside from the applications for sus-tainable use or for recovery of areasdegraded by mining the isolation amongoutcrops and plant and physiologicaladaptations make these environments amodel system for fundamental ecologicaland evolutionary questions such as pat-terns of species richness and distributionof species
BIODIVERSITY LOSS AND CON-SERVATION STATUS
Habitat loss and alteration have long beenrecognized as leading threats to worldbiodiversity In Brazilian ironstone out-crops this process occurs basically inassociation with mining activities Recent-ly this historical regional vocation hasbeen heavily accelerated as a consequenceof the economic emergence of Chinawhich has generated unprecedented de-mand for raw materials worldwide inparticular high-quality iron ore a phe-nomenon that has been termed lsquolsquothe Chinaeffectrsquorsquo in the commodities jargon Miningactivities contribute heavily to the Brazil-ian gross domestic product (GDP) In2000 the iron ore produced in the regionaccounted for 12 of the total value ofBrazilian mineral production excludingthe fossil fuels petroleum and gas (6)
Most floristic surveys of ironstoneoutcrops in the Iron Quadrangle are veryrecent Of the handful outcrops surveyedonly one is located within a conservationunit The others are located in areas ownedby mining companies which unfortunatelyreflects the vulnerable status of thisecosystem The mineral rights granted toindustry until 2002 cover an area of207 000 ha of the Iron Quadrangle Thisrepresents roughly 28 of the total IronQuadrangle area and probably 90 of allironstone outcrops in the region andillustrates that iron-ore exploitation over-laps heavily with these environments
Currently there are nine national parksin southeast Brazil that contain rockoutcrops and these are distributedthroughout extensive mountain rangessuch as the Mantiqueira and Serra doMar (granite outcrops) and Canastra andEspinhaco (sandstone outcrops) whichtogether cover 679 000 ha In the stateof Minas Gerais alone there are 14 stateparks that together cover around 212 000
Table 1 Public conservation units in southeast Brazil containing rock outcrops
Ambio Vol 37 No 4 June 2008 325 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
soil The third classification unit (calledlsquolsquotypersquorsquo) divides groups with grasslanddensity based on dominant plant specieswithin the grass community
Grassland Classification
The native grasslands of Naqu Prefecturewere subdivided into 4 classes 10 groupsand 32 types The distribution of grasslandclasses was identical to the geographic-climatic zones and included bush meadowalpine meadow alpine steppe and desertsteppe which form a horizontal-zonalpattern
Bush Meadow
The bush meadow class is distributedmainly over the hilly areas in the easterncounties of Naqu (eg Jiali SuoxianBiru and Baqing) where the climate iswet and comparatively temperate Theannual precipitation ranges from 579 mmto 650 mm with 80 occurring in thegrowing season (200ndash224 d) Averageannual temperature ranges from 158C to358C Owing to the diversified ecologicalconditions caused by topographic varia-tion the farming systems are mixed withlarge areas of native pasture in the lowlandand river valleys already converted tograin and cash crops Wheat peas rapepotato millet corn and buckwheat aremajor crops in these counties as well astraditional highland barley Yak andTibetan sheep are the major grazinglivestock with yaks accounting for 40of the prefecture livestock because they areso well adapted to the wet climate andhighland conditions Cattle and horses arealso important although cattle are mainlykept for use as draft animals for cropcultivation The emergence of the mixedfarming systems has led to peasantsbecoming settled in villages which in turnhas resulted in the development of animalhusbandry methods that differ significant-ly from the traditional nomadism in thepure pastoral areas The use of lowlandsand river valleys for crop production hasshifted livestock grazing to the hilly areasAlthough the grasslands are abundantprecipitous terrain and forestry landsrestrict grazing activities to certain alti-tudes (between 4200 and 4600 m) andplaces with relatively gentle slopes (258)Grasslands with these features account for8 of total usable grassland area in theprefecture Within this restricted usablegrassland area one typical group grami-neae is identified On the north-facingslopes between 4300 and 4600 m Rhodo-dendron nivale Hook f are dominant inassociation with Sibiraea angustata Hand-Mazz Spiraea alpina Pall and Potentillafruticosa L which are often used by yakand cattle Above 4700 m herbs graduallyreplace the dominant bushes On thesouth-facing slopes between 4200 and4500 m Elymus nutans Griseb Festuca
ovina L and Poa annua L are dominantin association with Kobresia pygmaeaKobresia humilis and Sabina tibeticaKom Because of the high foraging valueof these herbs and the relatively warmconditions yaks sheep cattle and horsesare intensively grazed on the south-facingslopes in the summer periods causingsevere overgrazing In winter livestockare grazed near the villages on thescattered grassland in the valleys andlowlands and supplemented with cropresidues and hays
Alpine Meadow
Alpine meadow is distributed over theriver terraces valleys and alluvial fans inthe west parts of the four eastern countieslarge areas of Naqu and Nierong and partof Anduo County It is the major grass-land class for livestock production in theprefecture accounting for 43 of the totalusable grassland area Cyperaceae formthe most abundant and forageable groupwhich accounts for 73 of the grasslandarea in this class Four grassland groupswere identified in this class based on theforaging values of plants and the meso-topography This vegetation is widelydistributed over flatter highlands valleysand sunny sides of hills over an altituderange between 4000 and 5200 m in the eastand central parts (eg Biru Suoxian JaliBaqing Naqu Nierong and Ando) Theclimate is suitable for this grassland groupthat prefers cold and wet climatic condi-tions with a protracted cold season as longas 8 mo and average rainfall of 400 mmThe K pygmaea grassland is the majortype and provides the best summer andautumn grazing for sheep and yaks in theprefecture as a result of its high foragingvalue and flatter terrain Although thecomposition of the grassland is relativelycomplex K pygmaea generally dominatesthe community with Sarracenia purpureaPoligonum macrophyllum D Don and Enutans present as subdominants Somehigher producing Kobresia grasslands arecut for hay production Overgrazingdrought and rodents are thought to beresponsible for the severe degradation ofthis grassland type
The gramineae form the next importantgrassland group in the class of alpinemeadow Kobresia pygmaea has a strongecological adaptation that enables it todominate plant communities above 5300m with cushion plants as a subdominantThis vegetation is mainly distributed in thetransition zones between alpine meadowand steppe classes and located in thevalley lake basin and saline meadowsbetween 4500 and 5200 m Three types ofgrassland within this group were identifiedbased on the dominant species whichincluded E nutans Achnatherum hookeriKeng and Puccinella himalaica Tzvel
Evergreen shrubs are the third group inthe alpine meadow that is located on the
north-facing sides of hills with altitudebetween 4200 and 4600 m in the easterncounties These types of grassland usuallyprovide winter and spring grazing forlivestock
Deciduous shrubs are the last group ofalpine meadow Rhododendron nivale dom-inate this group and the areas with lesscanopy density are usually used forgrazing yak and cattle in the warm seasonThis group is mainly distributed on north-facing hills with altitude between 4600 and4900 m in Naqu Suoxian Biru Jiali andBaqing It is also distributed on the south-facing sides of hills at 4000 and 4500 mwith P fruticosa and Elsholtzia fruticosaKehd as the dominant species Cutting byfarmers for household fuel for a longperiod of time has reduced canopy densityover large areas that are now used asgrazing lands for sheep yak and cattleThe areas with altitude of 4600 to 4900 mare usually used as grazing in the warmseason and the grasslands below thesealtitudes are used in the cold season
Alpine Steppe
Alpine steppe accounts for 57 of thetotal grassland areas in the prefecture andis an important area of sheep and goatproduction It is mainly distributed in thecentral and west counties of WenbuShuanghu Shengzha Bange and Anduowhere the altitude ranges between 4400and 5000 m and the climate is cold dryand windy The annual rainfall increasesfrom 100 mm to 300 mm from west to eastPlant composition in this class is generallyless botanically complex than alpine mead-ow with only 5 to 15 species Gramineaeform a typical group in this class whichoccurs in the valleys river terraces lakebasins alluvial fans and lake plains to thesouthwest of Naqu Prefecture A repre-sentative species in this group is Spurpurea Cyperaceae dominated byCarex moorcroftii is usually distributednorthwest of Naqu prefecture Deciduoustrees and shrubs normally distributed inthe flood land and shady sides of the hillsare also used by livestock
Desert Steppe
Desert steppe is widely distributed in thesandy land of lake basins alluvial fansand slopes of hills between Kekexili andKunlun Mountains where the averagealtitude exceeds 5000 m and the climateis extremely cold and dry Annual rainfallaverages only 100 mm Grassland compo-sition is very simple and only includesthree to five species of which Carexcompacta with C moorcroftii and Spurpurea occur frequently Desert steppeareas are lsquolsquounpopulated areasrsquorsquo wherewildlife such as wild yak Tibetan wilddonkey Tibetan antelope wolf fox etcmay be found
Ambio Vol 37 No 4 June 2008 323 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
References and Notes
1 Statistical Bureau of Tibet 2005 Annual EconomicStatistical Data of Tibet Lasa Tibet Press (In Chinese)
2 Liu J Zhan J and Deng X 2005 Spatio-temporalpatterns and driving forces of urban land expansion inChina during the economic reform era Ambio 34 450ndash455
3 Gansu Grassland Ecological Research Institute 1991Grassland and Livestock Resources in Naqu Prefecture ofTibet Lanzhou Gansu Science and Technology Press(In Chinese)
5 Peng X 1985 The rules and systems of grasslandclassification in China Sichuan Grassland 2 13ndash15 (InChinese)
6 Zizhi H 1996 Introduction to Grassland ClassificationBeijing Agricultural Press (In Chinese)
7 This work has been supported by Chinarsquos Special Fundfor Major State Basic Research Project (2007CB714406)Knowledge Innovation Program of the Chinese Acade-my of Sciences (approved KZCX2-YW-313 and
KZCX1-Y-02) foundation of the Chinese State KeyLaboratory of Remote Sensing Science (KQ060006)
Wang LiwenThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 Chinawlw9585163com
Wei YaxingDepartment of Geography LiaoningNormal University Dalian 116029China
Niu ZhengThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 China
Synopsis
This synopsis was not peer reviewed
The Contribution of Ironstone Outcropsto Plant Diversity in the Iron Quadranglea Threatened Brazilian Landscape
INTRODUCTION
Due to the contribution of a hithertoneglected ecosystem one of the richestmineral provinces in the world at theheart of a center of floristic diversity mayprove much more diverse and vulnerablethan the current figures show
The Iron Quadrangle (local nameQuadrilatero Ferrıfero) located in south-east Brazil covers an area of approximate-ly 7200 km2 and represents one of the mostimportant and well-studied geological siteson the planet It is contained entirelywithin the wealthy state of Minas Geraisthe area of which is approximately 587 000km2 larger than France The Portuguesename lsquolsquogeneral minesrsquorsquo attests to thehistorical ties of this state with the miningindustry since colonial times Constitutedby very oldmdashArchean and Paleoprotero-zoicmdashterrains the Iron Quadrangle land-scape is presently a mosaic at the ecotoneof two Brazilian hotspots Cerrado andAtlantic Forest which have been pro-foundly transformed by human activitiesnamely urbanization and mining
The region is one of the leadingproducers of metallic minerals in theworld especially superficial iron ore Theintense mining activity entails a completealteration of the landscape with enormousimpacts on the local and regional biodi-versity The superficial iron crusts locallyknown as canga are the result of weath-
ering of minerals derived from banded-iron formations (BIFs) compact hematiteand limonite (1) and they are distributedon the tops and sides of some mountainsformed by the huge deposits of iron orethat set the limits of the Iron QuadrangleThese outcrops form islands on top of hillsat altitudes ranging from 1000 to2000 m
Currently there are about 50 iron-oreopencast mines the extents of which mayreach 2000 ha Opencast mining is highlyaggressive to the environment because theironstone outcrops and their associatedbiota are discarded so that the iron-oredeposits can be reached and the excava-tions can reach 300 m depth and exposethe water table Furthermore the wastederived from these activities contaminates
nearby watersheds with heavy metals andtoxic elements (2)
These outcrops harbor characteristicrupestral vegetation which is shrub-dom-inated together with a large number ofsedges grasses and orchids most of whichare epilithic Due to their very restrictedarea difficult access and because they areassociated with high-quality iron-ore de-posits the plant communities over cangaare among the most threatened and leaststudied in the otherwise thoroughly sur-veyed ecosystems of southeast BrazilUntil recently rupestral plant communi-ties in the region had been given nodifferentiation with respect to the type ofsubstrate that harbored them Henceplants growing over iron ore were fre-quently recorded together with those
General landscape of the Iron Quadrangleviewed from an ironstone outcrop
Partial view of an opencast iron-ore mineshowing the superficial crust removal
324 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
growing over sandstone or granite Thehistorical lack of differentiation amonglithologies has prevented us from fullycomprehending the role of the flora andfauna biodiversity associated with theseironstone outcrops Recent studies how-ever have begun to reveal that the plantcommunities over ironstone outcropswhich are almost exclusively found in theIron Quadrangle with exception of Car-ajas in north Brazil (equally threatened byiron-ore mining) have a floristic identityand an extremely high local and regionaldiversity that equals or surpasses those ofthe other two lithologies
Preliminary comparative surveysamong the two major outcrop types inthe Iron Quadrangle sandstone and iron-stone suggest that the plant communitiesestablished over the latter contribute moreheavily to the biodiversity of the regionthan had been previously imagined Inonly six ironstones outcrops recentlysurveyed which together barely reach100 ha 430 angiosperm species distributedamong 78 families were catalogued Thisnumber represents 36 of all the familiesin Brazil the country with the highestplant diversity Notably some of thesespecies are endemic to very few outcropswithin the Iron Quadrangle such as themilkweed Ditassa monocoronata and thecactus Arthrocereus glaziovii These sur-veys illustrate the need to acceleratestudies of this particular environmentwhich in contrast to the well-documentedand world-known sandstone outcrops (thepredominant rock type in the area) isundergoing increasing economic pressure
WHY RESEARCH IRONSTONEOUTCROPS
The Iron Quadrangle makes up thesouthern end of an orographic groupknown as Espinhaco Range which isrecognized as one of the regions withhighest floristic diversity in South Amer-ica having more than 30 endemicspecies most of which are associated withrock outcrop environments (3) Theseamong other peculiarities recently grantedthe Espinhaco Range the status of Bio-sphere Reserve by the United NationsEducational Scientific and Cultural Orga-nization
Following this lead and with the aim ofestablishing their identity an ongoingproject at the Federal University of MinasGerais is devoted to determining thecontribution of the flora on ironstoneoutcrops to the regional plant diversityand to ascertaining the conservation statusof these ecosystems throughout the IronQuadrangle The initiative which com-bines botanists and ecologists has alreadyrevealed a very high local diversity show-ing astonishing numbers such as 16species of vascular plants in a single squaremeter This variety is the result of the smallsize of plants the rich matrix in which theyare embedded and the mineral andtopographical heterogeneity of these out-crops which create distinct microhabitatsside by side and result in a uniqueassociation of plants (4) Aside from themore typical communities that are alsocommon to other lithologies virtuallynothing is known about two plant com-munities typical of ironstone outcropstemporal ponds and penumbral rockcommunities associated with cliffs andcave entrances
The high diversity contrasts with thesevere edapho-climatic conditions typicalof outcrops in general such as highultraviolet (UV) intensities daily thermalsubstrate variations that can reach 458Crapid water loss and poorly developed soilcover which in the case of ironstones arefurther aggravated by a high content ofheavy metals One of the most relevantplant communities for conservation inregions with intense mining activities aremetallophyle plants which encompassthose species that have mechanisms ofresistance tolerance or bioaccumulationregarding metals usually taxa that areendemic to metalliferous areas Thesecommunities are being investigated forecological services such as phytoextrac-tion phytostabilization and phytopro-spection At present several researchgroups are focusing on the conservationand sustainable use of these communitiesfollowing the recommendations of theConvention on Biological Diversity toidentify and conserve metallophyles Theserecommendations have even been pro-posed for inclusion in the EnvironmentalManagement System ISO 14 000 (5) Thisproposal is fundamental to the short-termconservation of plant communities onironstone outcrops because to date thereis no specific environmental legislationthat protects this ecosystem In Brazilthere are important regions with rockoutcrops rich in metals like the Iron
Quadrangle itself However metallophylecommunities in spite of their evidentenvironmental importance have yet tobecome the focus of attention
Aside from the applications for sus-tainable use or for recovery of areasdegraded by mining the isolation amongoutcrops and plant and physiologicaladaptations make these environments amodel system for fundamental ecologicaland evolutionary questions such as pat-terns of species richness and distributionof species
BIODIVERSITY LOSS AND CON-SERVATION STATUS
Habitat loss and alteration have long beenrecognized as leading threats to worldbiodiversity In Brazilian ironstone out-crops this process occurs basically inassociation with mining activities Recent-ly this historical regional vocation hasbeen heavily accelerated as a consequenceof the economic emergence of Chinawhich has generated unprecedented de-mand for raw materials worldwide inparticular high-quality iron ore a phe-nomenon that has been termed lsquolsquothe Chinaeffectrsquorsquo in the commodities jargon Miningactivities contribute heavily to the Brazil-ian gross domestic product (GDP) In2000 the iron ore produced in the regionaccounted for 12 of the total value ofBrazilian mineral production excludingthe fossil fuels petroleum and gas (6)
Most floristic surveys of ironstoneoutcrops in the Iron Quadrangle are veryrecent Of the handful outcrops surveyedonly one is located within a conservationunit The others are located in areas ownedby mining companies which unfortunatelyreflects the vulnerable status of thisecosystem The mineral rights granted toindustry until 2002 cover an area of207 000 ha of the Iron Quadrangle Thisrepresents roughly 28 of the total IronQuadrangle area and probably 90 of allironstone outcrops in the region andillustrates that iron-ore exploitation over-laps heavily with these environments
Currently there are nine national parksin southeast Brazil that contain rockoutcrops and these are distributedthroughout extensive mountain rangessuch as the Mantiqueira and Serra doMar (granite outcrops) and Canastra andEspinhaco (sandstone outcrops) whichtogether cover 679 000 ha In the stateof Minas Gerais alone there are 14 stateparks that together cover around 212 000
Table 1 Public conservation units in southeast Brazil containing rock outcrops
Ambio Vol 37 No 4 June 2008 325 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
References and Notes
1 Statistical Bureau of Tibet 2005 Annual EconomicStatistical Data of Tibet Lasa Tibet Press (In Chinese)
2 Liu J Zhan J and Deng X 2005 Spatio-temporalpatterns and driving forces of urban land expansion inChina during the economic reform era Ambio 34 450ndash455
3 Gansu Grassland Ecological Research Institute 1991Grassland and Livestock Resources in Naqu Prefecture ofTibet Lanzhou Gansu Science and Technology Press(In Chinese)
5 Peng X 1985 The rules and systems of grasslandclassification in China Sichuan Grassland 2 13ndash15 (InChinese)
6 Zizhi H 1996 Introduction to Grassland ClassificationBeijing Agricultural Press (In Chinese)
7 This work has been supported by Chinarsquos Special Fundfor Major State Basic Research Project (2007CB714406)Knowledge Innovation Program of the Chinese Acade-my of Sciences (approved KZCX2-YW-313 and
KZCX1-Y-02) foundation of the Chinese State KeyLaboratory of Remote Sensing Science (KQ060006)
Wang LiwenThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 Chinawlw9585163com
Wei YaxingDepartment of Geography LiaoningNormal University Dalian 116029China
Niu ZhengThe State Key Laboratory of RemoteSensing Science
Institute of Remote SensingApplications
Chinese Academy of SciencesBeijing 100101 China
Synopsis
This synopsis was not peer reviewed
The Contribution of Ironstone Outcropsto Plant Diversity in the Iron Quadranglea Threatened Brazilian Landscape
INTRODUCTION
Due to the contribution of a hithertoneglected ecosystem one of the richestmineral provinces in the world at theheart of a center of floristic diversity mayprove much more diverse and vulnerablethan the current figures show
The Iron Quadrangle (local nameQuadrilatero Ferrıfero) located in south-east Brazil covers an area of approximate-ly 7200 km2 and represents one of the mostimportant and well-studied geological siteson the planet It is contained entirelywithin the wealthy state of Minas Geraisthe area of which is approximately 587 000km2 larger than France The Portuguesename lsquolsquogeneral minesrsquorsquo attests to thehistorical ties of this state with the miningindustry since colonial times Constitutedby very oldmdashArchean and Paleoprotero-zoicmdashterrains the Iron Quadrangle land-scape is presently a mosaic at the ecotoneof two Brazilian hotspots Cerrado andAtlantic Forest which have been pro-foundly transformed by human activitiesnamely urbanization and mining
The region is one of the leadingproducers of metallic minerals in theworld especially superficial iron ore Theintense mining activity entails a completealteration of the landscape with enormousimpacts on the local and regional biodi-versity The superficial iron crusts locallyknown as canga are the result of weath-
ering of minerals derived from banded-iron formations (BIFs) compact hematiteand limonite (1) and they are distributedon the tops and sides of some mountainsformed by the huge deposits of iron orethat set the limits of the Iron QuadrangleThese outcrops form islands on top of hillsat altitudes ranging from 1000 to2000 m
Currently there are about 50 iron-oreopencast mines the extents of which mayreach 2000 ha Opencast mining is highlyaggressive to the environment because theironstone outcrops and their associatedbiota are discarded so that the iron-oredeposits can be reached and the excava-tions can reach 300 m depth and exposethe water table Furthermore the wastederived from these activities contaminates
nearby watersheds with heavy metals andtoxic elements (2)
These outcrops harbor characteristicrupestral vegetation which is shrub-dom-inated together with a large number ofsedges grasses and orchids most of whichare epilithic Due to their very restrictedarea difficult access and because they areassociated with high-quality iron-ore de-posits the plant communities over cangaare among the most threatened and leaststudied in the otherwise thoroughly sur-veyed ecosystems of southeast BrazilUntil recently rupestral plant communi-ties in the region had been given nodifferentiation with respect to the type ofsubstrate that harbored them Henceplants growing over iron ore were fre-quently recorded together with those
General landscape of the Iron Quadrangleviewed from an ironstone outcrop
Partial view of an opencast iron-ore mineshowing the superficial crust removal
324 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
growing over sandstone or granite Thehistorical lack of differentiation amonglithologies has prevented us from fullycomprehending the role of the flora andfauna biodiversity associated with theseironstone outcrops Recent studies how-ever have begun to reveal that the plantcommunities over ironstone outcropswhich are almost exclusively found in theIron Quadrangle with exception of Car-ajas in north Brazil (equally threatened byiron-ore mining) have a floristic identityand an extremely high local and regionaldiversity that equals or surpasses those ofthe other two lithologies
Preliminary comparative surveysamong the two major outcrop types inthe Iron Quadrangle sandstone and iron-stone suggest that the plant communitiesestablished over the latter contribute moreheavily to the biodiversity of the regionthan had been previously imagined Inonly six ironstones outcrops recentlysurveyed which together barely reach100 ha 430 angiosperm species distributedamong 78 families were catalogued Thisnumber represents 36 of all the familiesin Brazil the country with the highestplant diversity Notably some of thesespecies are endemic to very few outcropswithin the Iron Quadrangle such as themilkweed Ditassa monocoronata and thecactus Arthrocereus glaziovii These sur-veys illustrate the need to acceleratestudies of this particular environmentwhich in contrast to the well-documentedand world-known sandstone outcrops (thepredominant rock type in the area) isundergoing increasing economic pressure
WHY RESEARCH IRONSTONEOUTCROPS
The Iron Quadrangle makes up thesouthern end of an orographic groupknown as Espinhaco Range which isrecognized as one of the regions withhighest floristic diversity in South Amer-ica having more than 30 endemicspecies most of which are associated withrock outcrop environments (3) Theseamong other peculiarities recently grantedthe Espinhaco Range the status of Bio-sphere Reserve by the United NationsEducational Scientific and Cultural Orga-nization
Following this lead and with the aim ofestablishing their identity an ongoingproject at the Federal University of MinasGerais is devoted to determining thecontribution of the flora on ironstoneoutcrops to the regional plant diversityand to ascertaining the conservation statusof these ecosystems throughout the IronQuadrangle The initiative which com-bines botanists and ecologists has alreadyrevealed a very high local diversity show-ing astonishing numbers such as 16species of vascular plants in a single squaremeter This variety is the result of the smallsize of plants the rich matrix in which theyare embedded and the mineral andtopographical heterogeneity of these out-crops which create distinct microhabitatsside by side and result in a uniqueassociation of plants (4) Aside from themore typical communities that are alsocommon to other lithologies virtuallynothing is known about two plant com-munities typical of ironstone outcropstemporal ponds and penumbral rockcommunities associated with cliffs andcave entrances
The high diversity contrasts with thesevere edapho-climatic conditions typicalof outcrops in general such as highultraviolet (UV) intensities daily thermalsubstrate variations that can reach 458Crapid water loss and poorly developed soilcover which in the case of ironstones arefurther aggravated by a high content ofheavy metals One of the most relevantplant communities for conservation inregions with intense mining activities aremetallophyle plants which encompassthose species that have mechanisms ofresistance tolerance or bioaccumulationregarding metals usually taxa that areendemic to metalliferous areas Thesecommunities are being investigated forecological services such as phytoextrac-tion phytostabilization and phytopro-spection At present several researchgroups are focusing on the conservationand sustainable use of these communitiesfollowing the recommendations of theConvention on Biological Diversity toidentify and conserve metallophyles Theserecommendations have even been pro-posed for inclusion in the EnvironmentalManagement System ISO 14 000 (5) Thisproposal is fundamental to the short-termconservation of plant communities onironstone outcrops because to date thereis no specific environmental legislationthat protects this ecosystem In Brazilthere are important regions with rockoutcrops rich in metals like the Iron
Quadrangle itself However metallophylecommunities in spite of their evidentenvironmental importance have yet tobecome the focus of attention
Aside from the applications for sus-tainable use or for recovery of areasdegraded by mining the isolation amongoutcrops and plant and physiologicaladaptations make these environments amodel system for fundamental ecologicaland evolutionary questions such as pat-terns of species richness and distributionof species
BIODIVERSITY LOSS AND CON-SERVATION STATUS
Habitat loss and alteration have long beenrecognized as leading threats to worldbiodiversity In Brazilian ironstone out-crops this process occurs basically inassociation with mining activities Recent-ly this historical regional vocation hasbeen heavily accelerated as a consequenceof the economic emergence of Chinawhich has generated unprecedented de-mand for raw materials worldwide inparticular high-quality iron ore a phe-nomenon that has been termed lsquolsquothe Chinaeffectrsquorsquo in the commodities jargon Miningactivities contribute heavily to the Brazil-ian gross domestic product (GDP) In2000 the iron ore produced in the regionaccounted for 12 of the total value ofBrazilian mineral production excludingthe fossil fuels petroleum and gas (6)
Most floristic surveys of ironstoneoutcrops in the Iron Quadrangle are veryrecent Of the handful outcrops surveyedonly one is located within a conservationunit The others are located in areas ownedby mining companies which unfortunatelyreflects the vulnerable status of thisecosystem The mineral rights granted toindustry until 2002 cover an area of207 000 ha of the Iron Quadrangle Thisrepresents roughly 28 of the total IronQuadrangle area and probably 90 of allironstone outcrops in the region andillustrates that iron-ore exploitation over-laps heavily with these environments
Currently there are nine national parksin southeast Brazil that contain rockoutcrops and these are distributedthroughout extensive mountain rangessuch as the Mantiqueira and Serra doMar (granite outcrops) and Canastra andEspinhaco (sandstone outcrops) whichtogether cover 679 000 ha In the stateof Minas Gerais alone there are 14 stateparks that together cover around 212 000
Table 1 Public conservation units in southeast Brazil containing rock outcrops
Ambio Vol 37 No 4 June 2008 325 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
growing over sandstone or granite Thehistorical lack of differentiation amonglithologies has prevented us from fullycomprehending the role of the flora andfauna biodiversity associated with theseironstone outcrops Recent studies how-ever have begun to reveal that the plantcommunities over ironstone outcropswhich are almost exclusively found in theIron Quadrangle with exception of Car-ajas in north Brazil (equally threatened byiron-ore mining) have a floristic identityand an extremely high local and regionaldiversity that equals or surpasses those ofthe other two lithologies
Preliminary comparative surveysamong the two major outcrop types inthe Iron Quadrangle sandstone and iron-stone suggest that the plant communitiesestablished over the latter contribute moreheavily to the biodiversity of the regionthan had been previously imagined Inonly six ironstones outcrops recentlysurveyed which together barely reach100 ha 430 angiosperm species distributedamong 78 families were catalogued Thisnumber represents 36 of all the familiesin Brazil the country with the highestplant diversity Notably some of thesespecies are endemic to very few outcropswithin the Iron Quadrangle such as themilkweed Ditassa monocoronata and thecactus Arthrocereus glaziovii These sur-veys illustrate the need to acceleratestudies of this particular environmentwhich in contrast to the well-documentedand world-known sandstone outcrops (thepredominant rock type in the area) isundergoing increasing economic pressure
WHY RESEARCH IRONSTONEOUTCROPS
The Iron Quadrangle makes up thesouthern end of an orographic groupknown as Espinhaco Range which isrecognized as one of the regions withhighest floristic diversity in South Amer-ica having more than 30 endemicspecies most of which are associated withrock outcrop environments (3) Theseamong other peculiarities recently grantedthe Espinhaco Range the status of Bio-sphere Reserve by the United NationsEducational Scientific and Cultural Orga-nization
Following this lead and with the aim ofestablishing their identity an ongoingproject at the Federal University of MinasGerais is devoted to determining thecontribution of the flora on ironstoneoutcrops to the regional plant diversityand to ascertaining the conservation statusof these ecosystems throughout the IronQuadrangle The initiative which com-bines botanists and ecologists has alreadyrevealed a very high local diversity show-ing astonishing numbers such as 16species of vascular plants in a single squaremeter This variety is the result of the smallsize of plants the rich matrix in which theyare embedded and the mineral andtopographical heterogeneity of these out-crops which create distinct microhabitatsside by side and result in a uniqueassociation of plants (4) Aside from themore typical communities that are alsocommon to other lithologies virtuallynothing is known about two plant com-munities typical of ironstone outcropstemporal ponds and penumbral rockcommunities associated with cliffs andcave entrances
The high diversity contrasts with thesevere edapho-climatic conditions typicalof outcrops in general such as highultraviolet (UV) intensities daily thermalsubstrate variations that can reach 458Crapid water loss and poorly developed soilcover which in the case of ironstones arefurther aggravated by a high content ofheavy metals One of the most relevantplant communities for conservation inregions with intense mining activities aremetallophyle plants which encompassthose species that have mechanisms ofresistance tolerance or bioaccumulationregarding metals usually taxa that areendemic to metalliferous areas Thesecommunities are being investigated forecological services such as phytoextrac-tion phytostabilization and phytopro-spection At present several researchgroups are focusing on the conservationand sustainable use of these communitiesfollowing the recommendations of theConvention on Biological Diversity toidentify and conserve metallophyles Theserecommendations have even been pro-posed for inclusion in the EnvironmentalManagement System ISO 14 000 (5) Thisproposal is fundamental to the short-termconservation of plant communities onironstone outcrops because to date thereis no specific environmental legislationthat protects this ecosystem In Brazilthere are important regions with rockoutcrops rich in metals like the Iron
Quadrangle itself However metallophylecommunities in spite of their evidentenvironmental importance have yet tobecome the focus of attention
Aside from the applications for sus-tainable use or for recovery of areasdegraded by mining the isolation amongoutcrops and plant and physiologicaladaptations make these environments amodel system for fundamental ecologicaland evolutionary questions such as pat-terns of species richness and distributionof species
BIODIVERSITY LOSS AND CON-SERVATION STATUS
Habitat loss and alteration have long beenrecognized as leading threats to worldbiodiversity In Brazilian ironstone out-crops this process occurs basically inassociation with mining activities Recent-ly this historical regional vocation hasbeen heavily accelerated as a consequenceof the economic emergence of Chinawhich has generated unprecedented de-mand for raw materials worldwide inparticular high-quality iron ore a phe-nomenon that has been termed lsquolsquothe Chinaeffectrsquorsquo in the commodities jargon Miningactivities contribute heavily to the Brazil-ian gross domestic product (GDP) In2000 the iron ore produced in the regionaccounted for 12 of the total value ofBrazilian mineral production excludingthe fossil fuels petroleum and gas (6)
Most floristic surveys of ironstoneoutcrops in the Iron Quadrangle are veryrecent Of the handful outcrops surveyedonly one is located within a conservationunit The others are located in areas ownedby mining companies which unfortunatelyreflects the vulnerable status of thisecosystem The mineral rights granted toindustry until 2002 cover an area of207 000 ha of the Iron Quadrangle Thisrepresents roughly 28 of the total IronQuadrangle area and probably 90 of allironstone outcrops in the region andillustrates that iron-ore exploitation over-laps heavily with these environments
Currently there are nine national parksin southeast Brazil that contain rockoutcrops and these are distributedthroughout extensive mountain rangessuch as the Mantiqueira and Serra doMar (granite outcrops) and Canastra andEspinhaco (sandstone outcrops) whichtogether cover 679 000 ha In the stateof Minas Gerais alone there are 14 stateparks that together cover around 212 000
Table 1 Public conservation units in southeast Brazil containing rock outcrops
Ambio Vol 37 No 4 June 2008 325 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
ha Only one of these however encloses afew mountaintops with ironstone outcrops(Table 1) In order to boost regulatorymeasures to protect these ecosystemswhile maintaining sustainable mining ac-tivities in the region a sound proof of thebiological value and floristic identity ofthese outcrops is mandatory and urgent
References and Notes
1 Dorr JN 1964 Supergene iron ores of Minas GeraisBrazil Econ Geol 59 1203ndash1240
2 Veado MARV Arantes IA Oliveira AH Almei-da MRMG Miguel RA Severo MI and Cab-aleiro HL 2006 Metal pollution in the environment ofMinas Gerais State Brazil Environ Monit Assess 117157ndash172
3 Giulietti AM Pirani JR and Harley RM 1997Espinhaco Range region Eastern Brazil In Centres ofPlant Diversity A Guide and Strategy for Their
Conservation Vol 3 The Americas Davis SD Hey-wood VH Herrera-MacBryde O Villa-Lobos J andHamilton AC (eds) WWFIUCN Publications UnitCambridge pp 397ndash404
4 Jacobi CM Carmo FF Vincent RC and Steh-mann JR 2007 Plant communities on ironstoneoutcropsmdasha diverse and endangered Brazilian ecosys-tem Biodivers Conserv 16 2185ndash2200
5 Whiting SN Reeves RD Richards D JohnsonMS Cooke JA Malaisse F Paton A SmithJAC et al 2004 Research priorities for conservationof metallophyte biodiversity and their potential forrestoration and site remediation Restor Ecol 12 106ndash116
6 Brazilian Mining Institute (IBRAM) 2003 Contributionof IBRAM to the Ecological-Economic Zonation andEnvironmental Planning of Municipalities Integrating theSouth Environmental Protection Area APA Sul IBRAMBrasılia 322 pp (In Portuguese)
7 This research was supported by FAPEM IG (MinasGerais Research Funding Agency grant CRA 80606)Collection permits were issued by IBAMA (BrazilianInstitute of Environment and Renewable NaturalResources) and IEFMG (Minas Gerais Forest Insti-tute)
Claudia Maria Jacobijacobiicbufmgbr
Flavio Fonseca do Carmoflaviodaserraclick21combr
Their addressDepartamento de Biologia GeralInstituto de Ciencias BiologicasUniversidade Federal deMinas Gerais
Avenida Antonio Carlos 662731270-901 Belo Horizonte ndash MG
Synopsis
This synopsis was not peer reviewed
Applying a Reverse Auction to ReduceStormwater Runoff
The effects of stormwater runoff onstream ecosystems are exacerbated byurbanization and the concurrent increasein impervious surface area in a watershedProliferation of impervious surfaces cre-ates higher peak flows and higher flowvolume during storm events and it in-creases the frequency of flows that result instream-habitat degradation pollutantloading and biotic impairment Currenttrends suggest that stormwater manage-ment should focus on restoring naturaldrainage processes and through small-scale decentralized efforts at the commu-nity level (1) Recent efforts by the USEnvironmental Protection Agency (USEPA) are focusing attention on the poten-tial use of what is being called greeninfrastructure to control stormwater flows(2) The US EPArsquos green infrastructurewebsite highlights a number of municipal-ities ranging from large cities such asNew York and Atlanta to smaller com-munities nationwide that have adoptedgreen infrastructure practices as part oftheir solution to stormwater and wastewa-ter management Green infrastructureprojects have resulted from two regulatoryavenues i) the implementation of theNational Pollutant Discharge EliminationSystem Phase I and Phase II stormwaterregulations for municipal dischargers andii) enforcement actions for combined andsanitary sewer overflows (CSO and SSO)where the alleged violators agree toundertake Supplemental Environmental
Projects (SEP) in exchange for mitigationof monetary penalties These SEP arebased on the premise detailed in theNational Resource Defense Councilrsquos2006 report Rooftops to Rivers (3) thatthey will control stormwater volume at thesource thereby reducing overall volume inthe system during storm events
Incentives for commercial properties toadopt stormwater runoff control are usu-ally employed through command-and-control tactics such as stormwater feesand rebates for implementation of certainbest management practices (BMP) Inrecently built housing developmentsaround the country in part due toincreased awareness of the inimical effectsof stormwater runoff municipalities oftenhave sufficient public support to be able torequire stormwater runoff BMP Howev-er property rights issues and lack ofimpervious surface restrictions during pastbuilding periods conspire to cause builtresidential property to be one of thehardest-to-control sources of stormwaterrunoff Parikh et al (4) suggested a reverseauction as the preferred economic mecha-nism to create incentives for constructionof retrofit low-technology stormwaterrunoff retention practices in establishedresidential neighborhoods Currently thepopular alternative is to offer a fixedpayment to residents to install certainBMP on their property (5) We show theauction to be more cost effective
The Shepherd Creek Project initiatedin 2003 by the US EPArsquos Office ofResearch and Development used a reverseauction mechanism as an incentive toconvince homeowners in an urban resi-dential neighborhood in Cincinnati OHto accept rain gardens and rain barrels ontheir properties as a means to reducestormwater runoff In the spring of 2007we conducted a reverse auction in theShepherd Creek neighborhood The auc-tion was designed to compensate residentsfor their costs of adopting BMP (rainbarrels and rain gardens) on their proper-ty Each of approximately 350 homeown-ers residing in the neighborhood receivedone educational mailing and one doorhanging that summarized informationregarding the practical benefits of raingardens and rain barrels their appearancetheir hydrological effectiveness and theirpurported effect on stream ecology Usinga bid form that was mailed to each homeapproximately two weeks after the infor-mational material participants submittedbids for the minimum compensation thatthey would require to accept a rain gardenandor up to four rain barrels A discrim-inative price auction was employed be-cause of its theoretical lsquolsquotruth-revelationrsquorsquoproperties including optimal biddingstrategy and it would reflect the actualopportunity cost of BMP adoption
The goal was to pay those landownerswho adopted the most effective BMP atthe lowest price Individual bids were
326 Ambio Vol 37 No 4 June 2008 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
26 W Martin Luther King DriveCincinnati Ohio 45268 USA
Ambio Vol 37 No 4 June 2008 327 Royal Swedish Academy of Sciences 2008httpwwwambiokvase
Climate Change Policy IPCC Consensus Is Not Enough
Grassland Classification in Naqu Prefecture of Tibet
The Contribution of Ironstone Outcrops to Plant Diversity in the Iron Quadrangle a Threatened Brazilian Landscape
Applying a Reverse Auction to Reduce Stormwater Runoff
assessed for their relative acceptabilitybased on the bid price the cost ofinstallation and the environmental benefitindex (EBI) which is a measure of theinfiltration impact of a given propertyBids for rain gardens and rain barrels wereevaluated and ranked separately EBI forthe rain gardens was determined using i)percent total impervious area (TIA) on theparcel ii) soil drainage characteristics andiii) proximity to a stream The environ-mental value for BMP installation ismaximized where there is high TIA onthe parcel soils have comparatively lowcapacity for drainage and the property isin close proximity to stream channelsRain barrels were scored based on percentof TIA currently attached to the stormsewer The scoring process was designed tobe a simple informative and repeatabletechnique for objectively quantifying thepotential environmental value of placingBMP on the property
There were 57 bids for rain gardenswhich were ranked according to EBI-weighted bid amount of those 56 bidswere accepted and 50 rain gardens wereinstalled Opportunity cost was taken to bethe bid amounts which ranged from USD0 to USD 500 for a total of USD 2465across the 50 parcels Based on an averagecost of installation (USD 1500) wecalculated cost per cubic meter of deten-tion as follows ([50 3 USD 1500] thorn USD2465)(50 3 428) This assumes a 428 m3
detention capacity per rain garden Totalstorm water detained with this assumptionis 214 m3 the average cost was USD 1549per homeowner and we calculated anaverage cost of USD 362 per cubic meterof stormwater runoff detained via BMPover all properties in the study areaAssuming those who bid USD 0 werethose who would have participated fol-lowing an education campaign but with-out the economic incentives we calculated30 3 USD 150030 3 428 In this casestorm water detained is 128 m3 and theaverage cost of stormwater runoff de-tained via BMP over all properties in thestudy area is USD 350 per cubic meterHad we not used an auction to determinethe different will ingness-to-acceptamounts of different homeowners andjust offered the flat amount needed (USD250) to cause the acceptance of the samenumber of rain gardens costs would beUSD 409 per cubic meter The flat pricewas by far the least cost-effective way toincentivize a decentralized approach tocontrol the stormwater runoff from thisarea Based on these data an educationalcampaign is expected to be the cheapestmethod for encouraging homeowners toaccept free rain gardens however toencourage additional acceptance and run-off reduction capacity beyond the initial60 of homeowners (those who bid USD0) the auction proves to be cost effective
For rain barrels there were 60 bids for118 units and bids ranged from USD 0 toUSD 250 per barrel One hundred barrels
were installed for a total bid payout ofUSD 2482 Each barrel cost approximate-ly USD 250 including installation andheld either 021 m3 (23 units) or 028 m3
(77 units) Total detention volume was264 m3 and we calculated the cost pervolume of detention as USD 1043 percubic meter If we as in the rain gardenexample assume those homeowners whogave a zero bid (37 bids for 63 barrels)would have participated had there beenjust an educational campaign the cost ofdetention is approximately USD 929 percubic meter Had we paid a flat rate perrain barrel of USD 125 (the amount of thehighest accepted per-barrel bid) cost fordetention would have been USD 1421 percubic meter
Disconnection of impervious surfacesand infiltration or retention of runoff hasbeen proposed as necessary to improve thehealth of freshwater ecosystems in urban-ized areas (6) however the practicalsolutions for encouraging enough mitiga-tion within catchments to observe down-stream improvements are unknown TheShepherd Creek Project is structured usinga before-after control-impact design andthree years of pre-implementation moni-toring at the watershed and neighborhoodscales We have now begun three years ofpostimplementation monitoring to deter-mine if the reverse auction resulted in theinstallation of sufficient stormwater con-trols to effect an ultimate improvement instream hydrology water chemistry andbiotic integrity
Not only does this project highlight thecost-effective properties of the reverseauction as an allocation mechanism itstresses the need for long-term monitoringof green infrastructure projects By cou-pling the economic mechanism with thephysical monitoring we can better under-stand the role of green infrastructure in theadvancement of environmental protectionin urbanized areas and we can quantify itseconomic benefits and costs
References and Notes
1 Gleick PH 2003 Global freshwater resources soft-path solutions for the 21st century Science 302 1524ndash1528
2 US EPA 2007 Managing wet weather with greenin f ras t ructure (ht tp c fpub epa govnpdes greeninfrastructurecfm)
3 Kloss C and Calarusse C 2006 Rooftops to RiversGreen Strategies for Controlling Stormwater and Com-bined Sewer Overflows National Resources DefenseCouncil New York 47 pp
4 Parikh P Taylor M Hoagland T Thurston HWand Shuster W 2005 At the intersection of hydrologyeconomics and law application of market mechanismsand incentives to reduce stormwater runoff Environ SciPol 8 133ndash144
5 Doll A Scodari PF and Lindsey G 1998 Credits aseconomic incentives for on-site stormwater managementissues and examples In Proceedings of the US Environ-mental Protection Agency National Conference on Retro-fit Opportunities for Water Resource Protection in UrbanEnvironments US EPA Chicago pp 113ndash117
6 Walsh CJ Fletcher TD and Ladson AR 2005Stream restoration in urban catchments through re-designing stormwater systems looking to the catchmentto save the stream J North Am Benthol Soc 24 690ndash705
7 Acknowledgment Joshua Templeton and MatthewClagett would like to thank the National ResearchCouncil for supporting them during their tenure at theUS EPA
Hale W ThurstonUS EPA Office of Research andDevelopment
