journa l homepage: www.e lsev ier .com/ locate /u fug
rban land use types contribute to grassland conservation: The example of Berlin
eonie K. Fischera,b,∗, Moritz von der Lippea,b, Ingo Kowarika,b
Technische Universität Berlin, Department of Ecology, Rothenburgstr. 12, 12165 Berlin, GermanyBerlin-Brandenburg Institute of Advanced Biodiversity Research (BBIB), 14195 Berlin, Germany
r t i c l e i n f o
eywords:gricultureiotope type mappingreen infrastructureawn vegetationatch connectivityrban meadow
a b s t r a c t
Urbanisation is an important driver of biodiversity loss, also contributing to habitat loss and fragmen-tation of grasslands at the urban-rural interface. While urban green spaces are known to include manygrassland habitats, it is uncertain to what extent urban land use types harbour grasslands of special con-servation interest and whether patch characteristics and connectivity of these differ from grasslands onagricultural land. By relating the city-wide biotope mapping to the land use mapping of Berlin, Germany,we assessed (1) to which specific urban land use types the major grassland biotope types belong, (2)differences in patch characteristics and connectivity, and (3) the conservation value of grassland patchesat a typological level by means of their legal protection status. Grasslands cover 5% of Berlin’s surface,and 43% of that area is assigned to legally protected grassland types. The majority of legally protectedgrassland (71%) lies on urban land opposed to 29% on agricultural land. Airports and historic parks, whichonly cover 2% of land in Berlin, contain one-third of all protected dry grasslands. Wet grassland is moreconfined to agricultural land. In airports and agricultural areas, grassland patches are larger but of a morecomplex shape than those in historic parks. In airports, grassland patches show greater connectivity as
they are situated in grassland-dominated surroundings. Grassland in historic parks appears to be morevulnerable due to smaller patch sizes and higher fragmentation. The example of Berlin demonstrates thatthe urban green infrastructure can clearly contribute to grassland conservation and may thus partiallycompensate for the decline of traditional grasslands in cultural landscapes. It will be important to involveresidents and landowners in urban grassland conservation and management because most grassland ofspecial conservation interest (57%) was found outside of conservation areas.
ntroduction
Urban growth has been identified as important driver of biodi-ersity loss (Hansen et al., 2005; Radeloff et al., 2009). This holdsarticularly true for near-natural grasslands, which decline at therban-rural interface in several regions all over the world (Cillierst al., 2004; Williams et al., 2005; Wittig et al., 2010). Urban sprawlhreatens grasslands in South Africa (O’Connor and Kuyler, 2009) asell as in Central European metropolitan areas (Wittig et al., 2010).oreover, fragmentation of cultural landscapes due to urbani-
ation contributes to the decrease in habitat diversity (Antrop,004).
Urbanisation thus adds to other drivers of grassland loss asso-iated with the agricultural practice: the increase in intensive
gricultural practices (Reidsma et al., 2006) and the abandonmentf unproductive agricultural land (Henle et al., 2008). In conse-uence, a sizable decrease in grassland habitats and diversity has
been reported for Central Europe (Poschlod et al., 2005). In north-ern Germany, for example, grassland species richness decreased by30–50% during a 50 year period (Wesche et al., 2012).
At the same time, urban areas have been shown to be rich inplant species, because the highly heterogeneous habitat mosaic ofurban spaces harbours high numbers of both native and introducedspecies (Kowarik, 1990; Kühn et al., 2004; Wania et al., 2006).Previous studies illustrate that different components of the urbangreen infrastructure comprise grassland habitats and associatedspecies of plants and animals: domestic gardens (Thompson et al.,2004; Politi Bertoncini et al., 2012), parks (Cornelis and Hermy,2004; DeCandido et al., 2007), golf courses (Hudson and Bird, 2009;Saarikivi et al., 2010), airports (Caccamise et al., 1996; Kutschbach-Brohl et al., 2010) and other transportation habitats (Helden andLeather, 2004; Jantunen et al., 2006). This indicates chances forconserving grassland biodiversity in urban settings that could, atthe same time, enhance the functioning of an array of ecosystemservices (Niemelä et al., 2010; Kowarik, 2011).
Therefore, we here aim to provide the first comprehensiveassessment of the quantitative and qualitative occurrence andspatial arrangement of major grassland types within a metropoli-tan area at the habitat level. Berlin, Germany, offers excellent
pportunities for such analyses since an existing biotope mappingSenStadt, 2008a) provides sound data on the spatial distributionf grassland types at the city scale. The assignment of a biotopeatch to a biotope type is thereby bound to a strict analysis of
ts floristic and faunistic composition that is usually determinedn a field survey. That is, different to studies on species level, weere work on the basis of biotope types (habitat level) and use the
nformation on biotope patches as our source material. Due to theccurrence of species of special conservation interest, some of theapped biotope types are automatically covered by a legal protec-
ion status due to Berlin’s Nature Conservation Act independent ofheir location within conservation areas. We could thus identify tohat extent grassland types of special conservation interest (i.e.,
egally protected grassland types) are confined to their traditionalgricultural context at the urban fringe or may exist in associationith non-agricultural urban land uses. Moreover, we explored the
xtent to which grassland types of special conservation interestccur outside of conservation areas.
We specifically addressed grassland habitats within agriculturaland – the traditional land use from which grasslands originaten Central Europe (Veen et al., 2009) – and three types of urbanand uses: (1) historic parks because these are known to show par-icularly high species richness and the occurrence of endangeredpecies and habitats (Maurer et al., 2000; Cornelis and Hermy,004; Ignatieva and Konechnaya, 2004; DeCandido et al., 2007;ümmerling and Müller, 2012), (2) airports, as these were found
o harbour large patches of semi-natural grasslands (Kutschbach-rohl et al., 2010), and (3) the remaining land use types (mostlycattered patches within recreational or residential areas).
In general, habitat quality depends on patch attributes suchs size, shape and connectivity to similar habitats, both in urbanBastin and Thomas, 1999; Öckinger et al., 2009) and agriculturalreas (Cousins and Aggemyr, 2008; Öster et al., 2009). Some patchttributes such as patch size influence a wide range of differentaxa (Lizée et al., 2012 for butterfly species; Sattler et al., 2010or arthropod species), often in combination with other parame-ers, for example vegetation structure (Meffert and Dziock, 2012or bird species). Other parameters more specifically relate to theccurrence of single taxa (Bräuniger et al., 2010). To our knowledge,xisting urban studies focus on the occurrence of certain taxa andheir relation to the urban matrix and/or patch characteristics (e.g.,vans et al., 2009; Öckinger et al., 2009), often specified for certainand uses (e.g., Parris, 2006 for parks and gardens; Lizée et al., 2012or parks) or habitat types (e.g., Sadler et al., 2006 for woodlands;
effert and Dziock, 2012 for wastelands).Therefore, our aim was (1) to focus on the habitat level and not
n single taxa, (2) to incorporate spatial data (biotope type, protec-ion status, land use) that cover a whole urban region, and thus (3) toombine spatial, quantitative and qualitative analyses to reveal dif-erences in patch quality between land use types independent fromhe species level. We hypothesise that (1) grassland types of specialonservation interest exist within urban land uses and occur alsoutside of conservation areas, (2) the distribution of major grass-and types (wet, mesic, dry, etc.) differs among land use categories,nd (3) habitat characteristics of grassland patches such as patchonnectivity differ between agricultural and urban land use.
ethods
iotope mapping
Apart from a few natural grasslands adjacent to wetland oratercourses, all grassland types in Berlin have developed due
o agricultural or horticultural practices. In Berlin, all biotopesere mapped nearly area-wide following a standardised method
an Greening 12 (2013) 263–272
(SenStadt, 2008a). The major grassland biotopes include wet grass-land, mesic grassland, dry grassland, fallow or ruderal grassland,herbaceous grassland, intensively used grassland, lawns, and tram-pled grassland.
In contrast to other biotope mappings (Qiu et al., 2010), majorbiotopes also include biotope types specifically found within urbanregions (e.g., lawns). They are further split into subtypes (e.g.,species-rich, old lawns in park), whereas each type is charac-terised by indicator species (Table 1). The mapped grassland unitsare thus directly linked with data at the species level. The stan-dardised biotope mapping method requires a biotope patch tobe mapped when it has a size of >500 m2 and a width of >10 m(SenStadt, 2008a). In general, grasslands in domestic gardens werenot mapped separately because they are subsumed within theappropriate housing category. Also, a few green spaces that maycontain grassland biotopes were mapped less specifically, for exam-ple some young parks were simply mapped as Park.
Legal protection status of biotopes
Article 26a of the Berlin Nature Conservation Act (SenStadt,2008b) defines a legal protection status for a range of grasslandtypes, which are rare, declining or harbour rare species. Majorbiotope types can contain both protected and unprotected sub-types (Table 1 and SenStadt, 2005). This legal protection statusholds automatically for all biotopes assigned to one of the legallyprotected types listed in the same Article, independent of theirownership or location within or outside of a conservation area.As the assignment of a biotope patch to a protected biotope typedepends on the presence of species with special conservation inter-est, this typological approach is backed by local biodiversity data.Legally protected biotopes must be mapped regardless of their size.The standardised biotope mapping method differentiates betweenprotected, potentially protected and unprotected grassland types(SenStadt, 2008a). To simplify our analyses, we merged the firsttwo types into the category ‘protected grasslands’.
Spatial analyses of grassland biotopes
We conducted an area-wide GIS-based analysis (ArcInfo, ver-sion 9.2; Spatial Analysis tools) of the Berlin biotope map (SenStadt,2008a) and the land use map of the Berlin Digital EnvironmentalAtlas (SenStadt, 2008c) to determine the agricultural or urban landuse category and protection status (‘protected’, ‘unprotected’) towhich each grassland biotope belonged. Our land use categorieswere (1) agriculture, (2) historic park (built before 1900), (3) air-port (in use or maintained) and (4) other urban areas. The categoryagriculture referred to areas used agriculturally. Although theseagricultural areas fell within the city limits of Berlin, they wererepresentative in scale and function of the land use that was themain origin of grasslands in Central Europe. In contrast, the otherthree categories represented typical urban land uses. These landuse categories were previously identified to harbour large patchesof semi-natural grasslands in urban areas (e.g., Cornelis and Hermy,2004 for parks; Kutschbach-Brohl et al., 2010 for airports). Berlinhas extensive conservation areas, especially in the periphery, andthese areas partially overlapped with the four land use categories.We quantified protected and unprotected grassland types withinconservation areas among all land use categories to determine theextent to which grassland types of special conservation interestalso occur outside of conservation areas.
We analysed spatial habitat characteristics to determine the
quantity and quality of grassland patches within each land use cat-egory. The parameters ‘patch size’ and ‘patch shape index’ wereassessed in Fragstats (version 3.3; conversion of vector data toraster data of 5 m cell size with conversion tool, ArcInfo for raster
L.K.Fischer
etal./U
rbanForestry
&U
rbanG
reening12
(2013)263–272
265Table 1All major grassland biotopes listed with a choice of subtypes, the underlying vegetation types, their legal protection status and characteristic species as defined in the description of biotope types of Berlin (SenStadt, 2005); §,generally protected by the Berlin Nature Conservation Act; FFH, types of habitats according to Attachment I of the FFH directive.
Major type Code Subtype Code Description Vegetation type Protection status Examples of characteristic plantspecies
05172 As 05171 Associations ofPolygonion avicularisBr.-Bl. 1931 ex Aich.1933
As 05171
2 & Urban Greening 12 (2013) 263–272
dd2g‘pamCsaot1ctG
gpwfoihg(
S
iatbbu2fmtgaaAS
R
G
eauMwpoa
P
t
Fig. 1. Location of grassland patches in Berlin according to the biotope map
66 L.K. Fischer et al. / Urban Forestry
ata analyses in Fragstats). We adjusted the cell size of our rasterata set at 5 m to include all patches from 10 m width (SenStadt,008a) even though these were lying at the cell borders. To describerassland connectivity, the parameters ‘patch surroundings’ and
patch connectivity’ were assessed in ArcInfo: For each grasslandatch >10 m2, we created a 100 m buffer around the edge. We chosebuffer distance of 100 m to account for an approximate maxi-um dispersal radius of herbaceous plants in urban settings (see
ousens et al., 2008 for details on dispersal distances). We mea-ured the amount of that buffer that was classified as (1) ‘pervious’nd ‘impervious’ or (2) ‘grassland’ and ‘non-grassland’. To avoidverlapping of the patch surroundings with empty cells outsidehe mapped city area, the focal patches had to lie within at least00 m of the city border. That is, within a 100 m buffer along theity borders, we removed all focal grassland patches but retainedhem for the determination of the patch surroundings in the otherIS layer.
‘Patch connectivity’ described the distance-area relation of allrassland patches within a radius of 1000 m around the focalatch. With the Hanski connectivity index (Hanski, 1994), we theneighted the size of surrounding patches by their distance to the
ocal patch by the equation Si = �exp(−˛dij) Aj, where A is the areaf the surrounding patch, dij is the distance between the surround-ng patch and the focal patch and ˛ is a dispersal factor betweenabitats kept at ˛ = 1 for all calculations. The distance betweenrassland patches was determined with the point distance toolinternal centroid of each grassland patch as point).
tatistical analyses
We compared the characteristics ‘patch size’, ‘patch shapendex’, ‘patch surroundings’ and ‘patch connectivity’ for protectednd unprotected grasslands for the land use category agricultureo all urban land use categories with the resampling method ofootstrapping (Manly, 2007) to determine significant differencesetween land use categories. Resampling allows comparing all landse types although patch numbers differ between categories (Roff,006). We resampled random means of each patch characteristicor the agricultural grassland patches 10,000 times. The random
eans were generated with as many random selections as werehe smallest number of entries within the urban land use cate-ories. The means of the land use categories historic park, airport,nd other urban areas were then compared to the land use categorygriculture using the confidence intervals of the resampled means.ll analyses were conducted with R (version 2.9, R Foundation fortatistical Computing, Vienna, Austria).
esults
rasslands and land use types
About 5% of the surface of Berlin is grassland. Grassland cov-rs one-fourth of the surface of the land use category historic park,bout two-thirds of the airport area, and one-third of the landse category agriculture. Other urban areas has 2% grassland cover.ost agricultural grassland is located in the city periphery (Fig. 1a),hereas grassland patches of the categories historic park and air-
ort can also be found in the inner city (Fig. 1b). Grassland patchesf other urban areas mostly occur in peripheral regions, similar togricultural grassland (Fig. 1c).
rotected grasslands
Altogether, 43% of all grassland area in Berlin can be assignedo grassland types with a legal protection status according to the
(SenStadt, 2008a), divided into the land use categories (a) agriculture (b) historicpark and airport (merged data), and (c) other urban areas.
Berlin Nature Conservation Act. Of this legally protected grass-land, 71% lies within urban and 29% within agricultural land uses(Fig. 2a). In both agriculture and other urban areas, about 45% of thetotal grassland area is protected. In the categories historic park andairport the proportion is about one-third protected (Fig. 2b).
The distribution of the major grassland biotope typesand their protected and unprotected subtypes differs widelyamong land use categories (Fig. 2c). Although the land usecategories historic park and airport cover less than 2% of
Berlin’s surface, together they include more than one-third ofall protected dry grassland (39% protected, 6% unprotected)and unprotected mesic grassland (32% unprotected, 11% pro-tected; Fig. 3). Wet grassland is common in both agriculture
ig. 2. Protected and unprotected grassland area in Berlin considered in terms of (a)nd other urban areas, and (c) the distribution of the major grassland biotope types wo the Berlin biotope map, a major biotope type can contain protected as well as un
46% protected, 45% unprotected) and other urban areas (53%rotected, 54% unprotected), but not in historic park (2% pro-ected, 0.1% unprotected) and is completely missing in airportsFig. 3).
In the category agriculture, more than half of the total grass-and area, and in the land use categories historic park and otherrban areas, about one-third of the total grassland area is situ-ted in conservation areas (Table 2). Nearly two-thirds of protectedrasslands in the agriculture category and 70% in the historicark category can be found within conservation areas. A signifi-
ant proportion of legally protected grassland types occur outsidef conservation areas in airports (100%) and other urban areas60%).
able 2rassland area and its proportion within conservation areas for agricultural and urban la
Land use category Total grasslandarea (ha)
Total protectedgrassland (%)
Agriculture 1036 44Historic park 116 31Airport 463 35Other urban areas 2004 46Berlin 3619 43
ltural and urban land use, (b) the land use categories historic park, airport, agricultureach land use category separated for protected and unprotected subtypes. Accordingted subtypes.
Patch size and shape
The patch characteristics of the urban land use cate-gories showed general differences when compared to agriculture(Table 3): With mean sizes of >2 ha, both protected and unpro-tected grassland patches are significantly larger in airports thanin the land use category agriculture. Protected grassland patchesin historic parks are significantly smaller than on agricultural land.Unprotected grassland patches in historic parks and all grasslandpatches in other urban areas are similar in size to those in the cate-
gory agriculture (Table 3).
In terms of patch shape complexity, agricultural grasslandsfall generally in the middle. Compared to agriculture, patches of
Table 3Differences between patch characteristics within and among land use categories. Tests were calculated after 10,000 randomizations from all pairwise comparisons ofprotected/unprotected grassland, and the land use category agriculture. N: number of patches of biotope type within a land use category. Patch numbers differ betweenanalyses as ‘patch shape’ and ‘patch size’ were assessed with raster data in Fragstats and ‘patch surroundings’ and ‘patch connectivity’ in ArcGIS with vector data. The rate ofresampled means for the land use category agriculture was determined by the smallest number of patches for each patch characteristic; relation describes whether the meanof an urban land use category is significantly higher (+) or lower (−) than the resampled mean of agriculture; P: two-tailed error probability. Significant differences betweenthe resampled values of grassland in agricultural areas and the mean values in urban land uses are indicated by ***P < 0.001, **P < 0.01, *P < 0.05.
Other urban areas 2084 27.14 − 2.65 × 10−19*** 2442 22.22 − 6.84 × 10−27***
Hanski index for connectivityAgriculture 464 0.30 503 0.35
1 × 10−26*** −27***
***
1 × 10
upitswa
P
ligaPvcplatloegcph
dt
Historic park 126 0.12 − 2.6Airport 140 0.64 + 0.0Other urban areas 1800 0.16 − 1.4
nprotected grasslands found in airports have a significantly higheratch shape complexity whereas patches of protected grasslands
n historic parks show a significantly smaller complexity. For pro-ected patches in airports and other urban areas we determined aimilar patch shape complexity when compared to agriculture, asell as for unprotected patches in historic parks and other urban
reas (Table 3).
atch connectivity
Grassland connectivity was assessed via the proportion of grass-and and impervious surfaces within buffers of 100 and the Hanskindex for 1000 m around grassland patches. In all land use cate-ories, the surroundings within 100 m of patches of both protectednd unprotected grassland types were at least two-thirds pervious.rotected grasslands in historic parks had a mean proportion of per-ious surroundings of 93% which significantly exceeds the land useategory agriculture (Table 3). In contrast, the mean proportion ofervious surroundings was significantly lower for protected grass-
and patches in airports and other urban areas when compared togriculture. For unprotected grassland patches, the mean propor-ion of pervious surroundings was significantly lower in the urbanand uses compared to agriculture (Fig. 4a). Within a 100 m radiusf protected and unprotected grassland patches in the land use cat-gory agriculture, more than 40% of the land consisted of otherrassland biotopes. The resampled means in agriculture signifi-antly differed from the urban land use categories, with grasslandatches in airports having more grassland in their surrounding, and
istoric parks and other urban areas less (Table 3).
Given the values of the Hanski index as a measure foristance-area related connectivity, both protected and unpro-ected grassland patches in airports show a significantly higher
611 0.21 − 2.59 × 10197 0.58 + 0.0***
−16*** 2150 0.17 − 4.98 × 10−46***
connectivity when compared to agriculture. For protected andunprotected grassland patches in historic parks and other urbanareas we determined a significantly lower connectivity than in thecategory agriculture (Table 3 and Fig. 4b).
Discussion
Protected grassland in urban areas
In the light of urbanisation and changes in the cultural land-scape, the importance of urban green spaces for biodiversitygenerally grows as previously illustrated for domestic gardens(Goddard et al., 2010; Cameron et al., 2012). Our area-wide assess-ment of grassland types in the metropolitan region of Berlinindicates further opportunities for grassland conservation in urbansettings. In our study, grassland of special conservation interest isnot exclusively confined to agriculture, the land use it has tradi-tionally been associated with in Central Europe (Veen et al., 2009).Today, the majority of both protected (71%) and unprotected grass-land (72%) was embedded in non-agricultural land use types ofBerlin (Fig. 2). Whereas agricultural land use appears to be highlyimportant for maintaining protected wet and mesic grasslands(Fig. 3), protected dry grasslands were mainly associated with otherurban land use types, especially airports and historic parks.
The existence of a large proportion of legally protected grass-lands outside of conservation areas (Table 2) suggests myriadopportunities for integrating grassland conservation into differ-ent land uses and in other parts of the urban green infrastructure.
Whereas in historic parks, the majority of legally protected grass-land (70%) overlaps with conservation areas, nearly two-thirds ofthe protected grasslands in the category other urban areas, andthe total protected grassland area of airports are located outside
L.K. Fischer et al. / Urban Forestry & Urb
Fcu
opo
lapbpmtott
P
iubpp
Fulp
ig. 3. Total area of wet, mesic and dry grassland for the land use categories agri-ulture, historic park, airport and other urban areas, differentiated for protected andnprotected grassland biotope patches in Berlin.
f conservation areas. This suggests a high potential for grasslandrotection under urban conditions but necessitates the cooperationf landowners and other stakeholders.
As we performed our analysis at the habitat (i.e., biotope type)evel, the legal protection status of grassland biotope types acteds an indicator for conservation value of the mapped grasslandatches. As with other biodiversity indicators, its validity muste demonstrated (Heink and Kowarik, 2010). Our study does notrovide any direct information about the species assemblages in theapped grassland types. Yet the assignment of a grassland patch
o a legally protected type on-site generally relies on the presencef typical species assemblages (Table 1). We therefore expect thathis formally attributed legal protection status of a patch reflectshe presence of typical as well as endangered grassland species.
atch quality in urban land uses
The value of a patch for nature conservation goes beyondts affiliation with any particular habitat type. Especially in an
rban context, patch characteristics that promote species exchangeetween patches (connectivity) and species persistence within aatch (e.g., patch size and shape) play a large role in determining theatch quality for different species. Although patch characteristics
ig. 4. Histogram for patch characteristics of 10,000 resampled means for the land use case categories. Symbols located outside the 95% confidence interval of the resampled mea
and use category agriculture. (a) Proportion of pervious surfaces within 100 m of protectedatches to other grassland patches in a 1000 m radius.
an Greening 12 (2013) 263–272 269
that affect habitat quality are highly species-dependent (Fischerand Lindenmayer, 2007; Bräuniger et al., 2010), studies have shownthat some characteristics such as patch size or connectivity affect agreat variety of taxonomic groups in a similar way, e.g., large habi-tat patches are often richer in species (Collinge, 1996; Drinnan,2005). Consistently, species richness of urban parks in Flanderswas positively related to grassland area within the parks (Cornelisand Hermy, 2004). In Birmingham, shape was found to influencespecies abundance, and slightly more species were found in round,i.e., less complex patches (Bastin and Thomas, 1999). Linked tocharacteristics on patch level, matrix parameters such as pervi-ous surface or built-up area surrounding a patch can influenceits habitat quality (Lizée et al., 2012). Habitat fragmentation, andaccordingly connectivity, is one of the most distinctive charac-teristics of urban landscapes (Robinson et al., 2005), and a majorconstraint for species richness of various taxonomic groups (Parris,2006; Sadler et al., 2006; Evans et al., 2009). In Prague, for example,the connectivity to the surrounding mosaic of green spaces affectedthe occurrence of butterfly and burnet species in grassland reserves(Kadlec et al., 2008).
The finding that most of the patch characteristics assessed inthis study differ significantly among land use types (Table 3) hasimportant implications for urban nature conservation. It demon-strates that patch quality of typical urban land uses indeed differsfrom that of agricultural remnants and that urban land use typescome with a distinctive set of patch characteristics.
Grassland patches in historic parks are significantly smaller andshow lower connectivity in both the nearby and more distant vicin-ity than agricultural grassland patches (Table 3 and Fig. 4). Patchshape is least complex in this land use type though. While thesmall patch size and low shape complexity probably result fromthe original garden design, the low connectivity is due to their loca-tion within a matrix of very divergent habitats. Within the parks,most grassland is bordered by woodland patches or water sepa-rating individual meadows. This is reflected in the high proportionof pervious surroundings in this land use category. On the largerscale, inner-city connectivity is low because of a high proportion ofbuilt-up areas around the parks, while grasslands in historic parksalong the city periphery are fragmented by large woodlands andwater bodies. Although they have a high level of fragmentationand are of small size, grasslands in historic parks are known toharbour high species richness, including rare species, as reported
from the Berlin region (Maurer et al., 2000; Peschel, 2000) andother cities (Wilhelm and Andres, 1998; Ignatieva and Konechnaya,2004; Kümmerling and Müller, 2012). This may be due to the longhabitat continuity and maintenance of meadows in historical parks
tegory agriculture compared to the means (indicated by symbols) of the urban landns (bars) demonstrate significantly smaller or higher mean values compared to thegrassland patches and (b) Hanski index for the connectivity of protected grassland
2 & Urban Greening 12 (2013) 263–272
(s
nacTsspt
tinpaat(Bop
snssemnAacjpga
P
osCeeili2sg
apOpab(
sa2p
70 L.K. Fischer et al. / Urban Forestry
Kowarik et al., 1998; Vähä-Piikkiö et al., 2004) that might compen-ate for disadvantageous patch characteristics.
The considerably larger patch size and connectivity bothear and far of grassland patches within airports compared togricultural land (Table 3) demonstrates that favourable patchharacteristics are not confined to traditional grassland systems.his can be explained by the large area of the airports them-elves. However, the high connectivity both at the local and largercale partly results from the connection of the numerous grasslandatches within each airport area rather than from a good connec-ivity to grasslands in the vicinity of the airports.
Due to their size and high proportion of diverse grassland habi-ats, airports represent core areas for grassland habitats in thenner city of Berlin. Size and patch connectivity suggest that inter-al patch dynamics and recruitment possibilities may ensure theersistence of species-rich grassland assemblages over time. Largend well connected grassland vegetation is also a prerequisite forspecific grassland fauna. Airport studies found a strong associa-
ion between typical grassland habitats and arthropod assemblagesJohn F. Kennedy International Airport, New York; Kutschbach-rohl et al., 2010), and for grassland bird species which weretherwise decreasing in the region (Atlantic City International Air-ort; Caccamise et al., 1996).
Grassland patches in the other urban areas have similar size andhape complexity to those in agricultural areas, but are less con-ected than these at all scales (Table 3). Most of these are highlycattered in regions of lower population and lower housing den-ities. Some are remnants of former agricultural grasslands nowmbedded in conservation areas or public green spaces. For theetropolitan region these remnant grasslands may form a coarse
etwork of habitats for species with a higher dispersal capacity.s shown for arable land, at a landscape scale even small habitatsnd an intermediate fragmentation of patches can contribute to theonservation of species (Tscharntke et al., 2002). Similarly, in con-unction with an urban green infrastructure network, the scatteredatches may function as interconnected habitats as has been sug-ested for domestic gardens (Goddard et al., 2010), in particular, asdiverse lawn flora can be found here (Thompson et al., 2004).
ractical implications
The quality of grassland habitats and associated species richnessften depends on the continuance of maintenance practices andites as studies have demonstrated in urban (Kingston et al., 2003;ornelis and Hermy, 2004; Celesti-Grapow et al., 2006; DeCandidot al., 2007) and agricultural areas (Johansson et al., 2008; Reitalut al., 2009). A North American study on insect species showed thatt is not the degree of urbanisation but the maintenance of grass-ands by grazing that is decisive for species richness as maintenancenfluenced the abundance of flowering plants (Kearns and Oliveras,009). In historic parks and airports, where a long continuance ofites is assumed, we found a comparable proportion of protectedrassland as determined for agricultural land use.
In historic parks, the continuance of traditional grassland man-gement is within the scope of both nature conservation and thereservation of historical garden monuments (Kowarik et al., 1998).ur study determined patch size of protected grasslands in historicarks as already critically low. Therefore, park maintenance shouldim at preserving the original extent of grassland patches, e.g.,y limiting encroaching shrubs and trees at the grassland ecotoneKingston et al., 2003).
Management strategies that support habitat patches as stepping
tones (Bierwagen, 2007) and consider thresholds of connectivityre important for urban areas (Parker and Mac Nally, 2002; Drinnan,005) and could improve the cohesion of the scattered grasslandatches in agricultural and urban areas. Yet for grassland plant
Fig. 5. Maintained grassland at the Tempelhof Airport, Berlin in 2011.
species, the functioning of traditional dispersal vectors associatedwith transhumance has dramatically declined in Central Europe(Poschlod and Bonn, 1998). It is an open question to what extent theproven dispersal of grassland species by people (Wichmann et al.,2009) or vehicles (von der Lippe and Kowarik, 2008) associatedwith maintenance or recreational activities in urban green spacescan substitute traditional dispersal vectors. Establishing new grass-lands on urban land by seed transfer from regional seed sources isa promising additional approach to counteract dispersal limitationwithin the urban fabric (Fischer et al., 2013a,b).
As both inner-city airports of Berlin will be out of use in the nearfuture, our study draws attention to the challenge of integrating tra-ditional grassland maintenance in future urban structures (Fig. 5).Similar to Berlin, internationally, the establishment of larger air-ports outside of towns mean that inner-city airports are convertedto other urban land uses (Dümpelmann, 2009), mainly to hous-ing estates, mixed with office buildings and technology parks (e.g.,Hong Kong Kai-Tak Airport; Croydon Airport, London; StapletonAirport, Denver). The example of the former airfield in Johan-nisthal, Berlin, shows that within the new built-up areas, largespaces can be set aside for recreation and nature conservation(Arbeitsgemeinschaft Monitoring Adlershof, 2006). It may be usefulto learn from other cities where new development and biodiversityconservation is being combined (e.g., Fornebu, Norway; Lindheim,2009). Yet as Berlin’s inner-city airports border densely popu-lated urban areas, aims of biodiversity conservation and optionsfor recreation of urban dwellers have to be balanced. This offers anexcellent opportunity to “conserve biodiversity where people live”(Miller and Hobbs, 2002).
Conclusions
A key finding of this study is that grasslands of special con-servation interest can be largely associated with the urban greeninfrastructure. Urban regions can thus contribute to the conserva-tion of grassland types which are subject to a marked decline inex-urban cultural landscapes. As our study was performed on thehabitat level, distinct changes in species composition along urban-rural gradients within habitat types remain to be studied. Hence,future research is strongly needed to test the extent to which typicalspecies assemblages of different grassland types can be sustainedon urban land.
The significant differences in major grassland types among
urban land use categories illustrate the need for setting priorities ingrassland conservation. For Berlin, our study highlights the promi-nent role of urban airports and historic parks in conserving drygrassland while wet grassland relies heavily on agricultural land
& Urb
uatga
tcsab
A
(EwmPR
R
A
A
B
B
B
C
C
C
C
C
C
C
C
D
D
D
E
F
F
F
G
H
L.K. Fischer et al. / Urban Forestry
se. Grassland patches in airports show unique characteristics suchs large patch size and a high connectivity which assist the persis-ence and exchange of endangered grassland species. In contrast,rasslands in historic parks appear to be vulnerable because of dis-dvantageous patch characteristics.
As a significant proportion of grassland with a high conserva-ion interest is located outside of conservation areas, strategies toonserve urban grasslands need to involve landowners and othertakeholders. This implies that a combination of approaches aimedt emphasising both biodiversity conservation and human well-eing in urban areas will be needed.
cknowledgements
This study was funded by the German Research FoundationDFG) as part of the graduate research training programme ‘Urbancology Berlin’ (GRK 780/III). We thank Holger Brandt (Senatsver-altung für Stadtentwicklung, Berlin) for providing the biotopeapping data base, one anonymous reviewer, Galina Churkina and
eter Meffert for helpful comments on early versions, and Kelaineavdin and Barbara Clucas for improving our English.
eferences
ntrop, M., 2004. Landscape change and the urbanization process in Europe. Land-scape and Urban Planning 67, 9–26.
rbeitsgemeinschaft Monitoring Adlershof, 2006. Monitoring im LandschaftsparkBerlin-Adlershof, 8. Bericht. Adlershof Projekt GmbH, Berlin.
astin, L., Thomas, C.D., 1999. The distribution of plant species in urban vegetationfragments. Landscape Ecology 14, 493–507.
ierwagen, B.G., 2007. Connectivity in urbanizing landscapes: the importance ofhabitat configuration, urban area size, and dispersal. Urban Ecosystems, 29–42.
räuniger, C., Knapp, S., Kühn, I., Klotz, S., 2010. Testing taxonomic and landscapesurrogates for biodiversity in an urban setting. Landscape and Urban Planning97, 283–295.
accamise, D., Reed, L.M., DeLay, L.S., Bennett, K.A., Dosch, J.J., 1996. The avian com-munities of a suburban grassland refugium: population studies at an airport inNortheastern United States. Acta Ornithologica 31, 3–13.
ameron, R.W.F., Blanusa, T., Taylor, J.E., Salisbury, A., Halstead, A.J., Henricot, B.,Thompson, K., 2012. The domestic garden – its contribution to urban greeninfrastructure. Urban Forestry & Urban Greening 11, 129–137.
elesti-Grapow, L., Pysek, P., Jarosík, V., Blasi, C., 2006. Determinants of native andalien species richness in the urban flora of Rome. Diversity and Distributions 12,490–501.
illiers, S.S., Müller, N., Drewes, E., 2004. Overview on urban nature conserva-tion: situation in the western-grassland biome of South Africa. Urban Forestry& Urban Greening 3, 49–62.
ollinge, S.K., 1996. Ecological consequences of habitat fragmentation: implica-tions for landscape architecture and planning. Landscape and Urban Planning36, 59–77.
ornelis, J., Hermy, M., 2004. Biodiversity relationships in urban and suburban parksin Flanders. Landscape and Urban Planning 69, 385–401.
ousens, R., Dytham, C., Law, R., 2008. Dispersal in Plants. A Population Perspective.Oxford University Press, Oxford.
ousins, S.A.O., Aggemyr, E., 2008. The influence of field shape, area and surroundinglandscape on plant species richness in grazed ex-fields. Biological Conservation141, 126–135.
eCandido, R., Calvanese, N., Alvarez, R.V., Brown, M.I., Nelson, T.M., 2007. Thenaturally occurring historical and extant flora of Central Park, New York City,New York 1857–2007. Journal of the Torrey Botanical Society 134, 552–569.
rinnan, I.N., 2005. The search for fragmentation thresholds in a Southern SydneySuburb. Biological Conservation 124, 339–349.
ümpelmann, S., 2009. Die Umnutzung von Flugplätzen: Der Orange County GreatPark südöstlich von Los Angeles. Angeles Stadt und Grün 58, 33–40.
ischer, J., Lindenmayer, D.B., 2007. Landscape modification and habitat fragmen-tation: a synthesis. Global Ecology and Biogeography 16, 265–280.
ischer, L.K., von der Lippe, M., Rillig, M.C., Kowarik, I., 2013a. Creating novel urbangrasslands by reintroducing native species in wasteland vegetation. BiologicalConservation 159, 119–126.
ischer, L.K., von der Lippe, M., Kowarik, I., 2013b. Urban grassland restoration:which plant traits make desired species successful colonizers? Applied Vegeta-tion Science 16, 272–285.
oddard, M.A., Dougill, A.J., Benton, T.G., 2010. Scaling up from gardens: biodiversityconservation in urban environments. Trends in Ecology & Evolution 25, 90–98.
ansen, A.J., Knight, R.L., Marzluff, J.M., Powell, S., Brown, K., Gude, P.H., Jones, A.,2005. Effects of exurban development on biodiversity: patterns, mechanisms,and research needs. Ecological Applications 15, 1893–1905.
an Greening 12 (2013) 263–272 271
Hanski, I., 1994. A practical model of metapopulation dynamics. Journal of AnimalEcology 63, 151–162.
Heink, U., Kowarik, I., 2010. What criteria should be used to select biodiversityindicators? Biodiversity and Conservation 19, 3769–3797.
Helden, A.J., Leather, S.R., 2004. Biodiversity on urban roundabouts – hemiptera,management and the species-area relationship. Basic and Applied Ecology 5,367–377.
Henle, K., Alard, D., Clitherow, J., Cobb, P., Firbank, L., Kull, T., McCracken, D., Moritz,R.F.A., Niemelä, J., Rebane, M., Wascher, D., Watt, A., Young, J., 2008. Identifyingand managing the conflicts between agriculture and biodiversity conservationin Europe – a review. Agriculture, Ecosystems & Environment 124, 60–71.
Hudson, M.-A.R., Bird, D.M., 2009. Recommendations for design and managementof golf courses and green spaces based on surveys of breeding bird communitiesin Montreal. Landscape and Urban Planning 92, 335–346.
Ignatieva, M., Konechnaya, G., 2004. Floristic investigations of historical parks in St.Petersburg, Russia. Urban Habitats 2, 1541–7115.
Jantunen, J., Saarinen, K., Valtonen, A., Saarnio, S., 2006. Grassland vegetationalong roads differing in size and traffic density. Annales Botanici Fennici 43,107–117.
Johansson, L.J., Hall, K., Prentice, H.C., Ihse, M., Reitalu, T., Sykes, M., Kindström, M.,2008. Semi-natural grassland continuity, long-term land-use change and plantspecies richness in an agricultural landscape on Öland, Sweden. Landscape andUrban Planning 84, 200–211.
Kadlec, T., Benes, J., Jarosík, V., Konvicka, M., 2008. Revisiting urban refuges: changesof butterfly and burnet fauna in Prague reserves over three decades. Landscapeand Urban Planning 85, 1–11.
Kearns, C.A., Oliveras, D.M., 2009. Environmental factors affecting bee diversity inurban and remote grassland plots in Boulder, Colorado. Journal of Insect Con-servation 13, 655–665.
Kingston, N., Lynn, D.E., Martin, J.R., Waldren, S., 2003. An overview of biodiversityfeatures in Dublin city urban parklands. Management of Environmental Quality:An International Journal 14, 556–570.
Kowarik, I., 1990. Some responses of flora and vegetation to urbanization in CentralEurope. In: Sukopp, H., Hejny, S., Kowarik, I. (Eds.), Plants and Plant Communitiesin the Urban Environment. SPB Academic Publishing, The Hague, pp. 45–74.
Kowarik, I., 2011. Novel urban ecosystems, biodiversity, and conservation. Environ-mental Pollution 159, 1974–1983.
Kowarik, I., Schmidt, E., Sigel, B. (Eds.), 1998. Naturschutz und Denkmalpflege. vdfHochschulverlag, Zürich.
Kühn, I., Brandl, R., Klotz, S., 2004. The flora of German cities is naturally speciesrich. Evolutionary Ecology Research 6, 749–764.
Kümmerling, M., Müller, N., 2012. The relationship between landscape design styleand the conservation value of parks: a case study of a historical park in Weimar,Germany. Landscape and Urban Planning 107, 111–117.
Kutschbach-Brohl, L., Washburn, B.E., Bernhardt, G.E., Chipman, R.B., Francoeur, L.C.,2010. Arthropods of a semi-natural grassland in an urban environment: the JohnF. Kennedy International Airport, New York. Journal of Insect Conservation 14,347–358.
Lindheim, T., 2009. Nansen Park, Oslo. From airport to landscape. Topos 66,22–27.
Lizée, M.H., Manel, S., Mauffrey, J.F., Tatoni, T., Deschamps-Cottin, M., 2012. Matrixconfiguration and patch isolation influences override the species-area relation-ship for urban butterfly communities. Landscape Ecology 27, 159–169.
Manly, B.F.J., 2007. Randomization, Bootstrap and Monte Carlo Methods in Biology.Chapman and Hall, Boca Raton.
Maurer, U., Peschel, T., Schmitz, S., 2000. The flora of selected urban land-use typesin Berlin and Potsdam with regard to nature conservation in cities. Landscapeand Urban Planning 46, 209–215.
Meffert, P.J., Dziock, F., 2012. What determines occurrence of threatened bird specieson urban wastelands? Biological Conservation 153, 87–96.
Miller, J.R., Hobbs, R.J., 2002. Conservation where people live and work. ConservationBiology 16, 330–337.
Niemelä, J., Saarela, S.R., Soderman, T., Kopperoinen, L., Yli-Pelkonen, V., Vare, S.,Kotze, D.J., 2010. Using the ecosystem services approach for better planningand conservation of urban green spaces: a Finland case study. Biodiversity andConservation 19, 3225–3243.
O’Connor, T.G., Kuyler, P., 2009. Impact of land use on the biodiversity integrity of themoist sub-biome of the grassland biome, South Africa. Journal of EnvironmentalManagement 90, 384–395.
Öckinger, E., Dannestam, A., Smith, H.G., 2009. The importance of fragmentationand habitat quality of urban grasslands for butterfly diversity. Landscape andUrban Planning 93, 31–37.
Öster, M., Ask, K., Römermann, C., Tackenberg, O., Eriksson, O., 2009. Plant coloniza-tion of ex-arable fields from adjacent species-rich grasslands: the importanceof dispersal vs. recruitment ability. Agriculture, Ecosystems & Environment 130,93–99.
Parker, M., Mac Nally, R., 2002. Habitat loss and the habitat fragmentation threshold:an experimental evaluation of impacts on richness and total abundances usinggrassland invertebrates. Biological Conservation 105, 217–229.
Peschel, T., 2000. Vegetationskundliche Untersuchungen der Wiesen- und Rasen-
gesellschaften historischer Gärten in Potsdam. ibidem, Stuttgart.
Politi Bertoncini, A., Machon, N., Pavoine, S., Muratet, A., 2012. Local gardening prac-tices shape urban lawn floristic communities. Landscape and Urban Planning105, 53–61.
2 & Urb
P
P
Q
R
R
R
R
R
S
S
S
S
S
72 L.K. Fischer et al. / Urban Forestry
oschlod, P., Bakker, J.P., Kahmen, S., 2005. Changing land use and its impact onbiodiversity. Basic and Applied Ecology 6, 93–98.
oschlod, P., Bonn, S., 1998. Changing dispersal processes in the central Europeanlandscape since the last ice age: an explanation for the actual decrease of plantspecies richness in different habitats? Acta Botanica Neerlandica 47, 27–44.
iu, L., Gao, T., Gunnarsson, A., Hammer, M., von Bothmer, R., 2010. A methodologi-cal study of biotope mapping in nature conservation. Urban Forestry & UrbanGreening 9, 161–166.
adeloff, V.C., Stewart, S.I., Hawbaker, T.J., Gimmi, U., Pidgeon, A.M., Flather, C.H.,Hammer, R.B., Helmers, D.P., 2009. Housing growth in and near United Statesprotected areas limits their conservation value. Proceedings of the NationalAcademy of Sciences of the United States of America 107, 940–945.
eidsma, P., Tekelenburg, T., van den Berg, M., Alkemade, R., 2006. Impacts of land-use change on biodiversity: an assessment of agricultural biodiversity in theEuropean Union. Agriculture, Ecosystems & Environment 114, 86–102.
eitalu, T., Sykes, M.T., Johansson, L.J., Lonn, M., Hall, K., Vandewalle, M., Prentice,H.C., 2009. Small-scale plant species richness and evenness in semi-naturalgrasslands respond differently to habitat fragmentation. Biological Conservation142, 899–908.
obinson, L., Newell, J.P., Marzluff, J.A., 2005. Twenty-five years of sprawl in the Seat-tle region: growth management responses and implications for conservation.Landscape and Urban Planning 71, 51–72.
off, D.D., 2006. Introduction to Computer-intensive Methods of Data Analysis inBiology. Cambridge University Press, Cambridge.
aarikivi, J., Idstrom, L., Venn, S., Niemelä, J., Kotze, D.J., 2010. Carabid beetle assem-blages associated with urban golf courses in the greater Helsinki area. EuropeanJournal of Entomology 107, 553–561.
adler, J.P., Small, E.C., Fiszpan, H., Telfer, M.G., Niemelä, J., 2006. Investigating envi-ronmental variation and landscape characteristics of an urban-rural gradientusing woodland carabid assemblages. Journal of Biogeography 33, 1126–1138.
attler, T., Duelli, P., Obrist, M.K., Arlettaz, R., Moretti, M., 2010. Response of arthro-pod species richness and functional groups to urban habitat structure and
management. Landscape Ecology 25, 941–954.
enStadt, 2005. Beschreibung der Biotoptypen Berlins. Senate Department for UrbanDevelopment.
enStadt, 2008a. Biotopkartierung. Senate Department for Urban Development,Berlin.
an Greening 12 (2013) 263–272
SenStadt, 2008b. Gesetz über Naturschutz und Landschaftspflege von Berlin.Berliner Naturschutzgesetz–NatSchGBln in der Fassung vom 3. November 2008.Senate Department for Urban Development.
SenStadt, 2008c. Berlin Digital Environmental Atlas. Land use “06.01 Actual Use ofBuilt-up areas” and “06.02 Inventory of Green and Open Spaces”. Senate Depart-ment for Urban Development.
Thompson, K., Hodgson, J.G., Smith, R.M., Warren, P.H., Gaston, K.J., 2004. Urbandomestic gardens (III): composition and diversity of lawn floras. Journal of Veg-etation Science 15, 373–378.
Tscharntke, T., Steffan-Dewenter, I., Kruess, A., Thies, C., 2002. Contribution of smallhabitat fragments to conservation of insect communities of grassland-croplandlandscapes. Ecological Applications 12, 354–363.
Vähä-Piikkiö, I., Kurtto, A., Hahkala, V., 2004. Preservation of indigenous vegetationin urban areas. Landscape and Urban Planning 68, 357–370.
Veen, P., Jefferson, R., Smidt, J., van der Straaten, J., 2009. Grasslands in Europe ofHigh Nature Value. KNNV Publishing, Zeist.
von der Lippe, M., Kowarik, I., 2008. Do cities export biodiversity? Traffic as dispersalvector across urban-rural gradients. Diversity and Distributions 14, 18–25.
Wania, A., Kühn, I., Klotz, S., 2006. Plant richness patterns in agricultural and urbanlandscapes in Central Germany – spatial gradients of species richness. Landscapeand Urban Planning 75, 97–110.
Wesche, K., Krause, B., Culmsee, H., Leuschner, C., 2012. Fifty years of change inCentral European grassland vegetation: large losses in species richness andanimal-pollinated plants. Biological Conservation 150, 76–85.
Wichmann, M.C., Alexander, M.J., Soons, M.B., Galsworthy, S., Dunne, L., Gould, R.,Fairfax, C., Niggemann, M., Hails, R.S., Bullock, J.M., 2009. Human-mediated dis-persal of seeds over long distances. Proceedings of the Royal Society B: BiologicalSciences 276, 523–532.
Wilhelm, M., Andres, F., 1998. Parkrasen und Parkwiesen in Zürich. In: Kowarik, I.,Schmidt, E., Sigel, B. (Eds.), Naturschutz und Denkmalpflege. vdf Hochschulver-lag, Zürich, pp. 221–227.
and local extinctions in natural grasslands along an urban-rural gradient. Journalof Ecology 93, 1203–1213.
Wittig, R., Becker, U., Nawrath, S., 2010. Grassland loss in the vicinity of a highlyprospering metropolitan area from 1867/68 to 2000: the example of the Taunus(Hesse, Germany) and its Vorland. Landscape and Urban Planning 95, 175–180.
