Terrestrial Carbon SequestrationTerrestrial Carbon SequestrationAdrian MartinAdrian Martin

Global terrestrial C budgetsGlobal terrestrial C budgets Historical C emissions from land use changeHistorical C emissions from land use change Global potential for LULUCF sequestrationGlobal potential for LULUCF sequestration ReforestationReforestation Managing agricultural landsManaging agricultural lands Institutional framework: Kyoto and CDMInstitutional framework: Kyoto and CDM Social issuesSocial issues

IIED (2002)

Carbon cycling on landCarbon cycling on land

270 PgC/yr dissolved in leaf water ~ 1/3 atmospheric C

120PgC/yr fixed through Photosynthesis

= Gross Primary Productivity

60Pg/yr plant growth= Net Primary Productivity

>½ directly released to atmosphere

60Pg/yr Respired by plants

60Pg/yr Net Primary Productivity

Net Ecosystem Productivity

Heterotrophic respirationBacteria, fungi

Herbivores

Net Biome Production

Releases through fire,harvests, soil erosion, …

Net Ecosystem ProductivityNet Ecosystem Productivity

Tropical Forests: 0.7- 5.9 MgC/ha/yrTropical Forests: 0.7- 5.9 MgC/ha/yr Temperate forests: 0.8 – 7.0 MgC/ha/yrTemperate forests: 0.8 – 7.0 MgC/ha/yr Boreal forests: (<0?) – 2.5 MgC/ha/yrBoreal forests: (<0?) – 2.5 MgC/ha/yr

(IPCC 2001)(IPCC 2001)

Global C02 Budgets (PgC/yr)Global C02 Budgets (PgC/yr)1980s1980s 1990s1990s

Atmosphere IncreaseAtmosphere Increase 3.3 3.3 ± 0.1± 0.1 3.2 3.2 ± 0.1± 0.1

Emissions (fossil fuel, cement)Emissions (fossil fuel, cement) 5.4 5.4 ± 0.3± 0.3 6.3 6.3 ± 0.4± 0.4

Ocean-atmosphere fluxOcean-atmosphere flux - 1.9 - 1.9 ± 0.6± 0.6 -1.7 -1.7 ± 0.5± 0.5

Land-atmosphere fluxLand-atmosphere flux

(net biome production)(net biome production)

-0.2 -0.2 ± 0.7± 0.7 -1.4 -1.4 ±0.7±0.7

- Land use change- Land use change 1.71.7

- Residual terrestrial sink- Residual terrestrial sink -1.9-1.9

Historical Losses of Terrestrial CarbonHistorical Losses of Terrestrial Carbon through through Land Use ChangeLand Use Change

Houghton (1990) estimates 121PgC lost 1850 – 1990Houghton (1990) estimates 121PgC lost 1850 – 1990 De Fries et al (1999) further 60PgC lost prior to 1850De Fries et al (1999) further 60PgC lost prior to 1850

Total 180PgC (280 from fossil fuels)Total 180PgC (280 from fossil fuels) Approx 40% of this in atmosphereApprox 40% of this in atmosphere Substantial (but ultimately limited) opportunities for Substantial (but ultimately limited) opportunities for

modifying above and below ground carbon storagemodifying above and below ground carbon storage

Deforestation (cont.)Deforestation (cont.)

Deforestation responsible for estimated 90% Deforestation responsible for estimated 90% of land use change emissions since 1850of land use change emissions since 1850

FAO (2001) Global Forest Resources FAO (2001) Global Forest Resources Assessment 2000:Assessment 2000:

Gross annual loss 1990-2000: 14.6 million ha.Gross annual loss 1990-2000: 14.6 million ha. Net annual loss 1990-2000: 9.4million ha.Net annual loss 1990-2000: 9.4million ha.

Forest Area Changes 1990-2000Forest Area Changes 1990-2000

TropicalTropical Non-tropicalNon-tropical

19901990 20002000 19901990 20002000

Natural Forest Natural Forest (Million Ha)(Million Ha)

19451945 18031803 18631863 18791879

Plantation Forest Plantation Forest (Million Ha)(Million Ha)

4848 6868 107107 119119

Source: FAO 2001

Main cause of loss in tropical areas: conversion to agriculture

Global Potential: LULUCFGlobal Potential: LULUCF

IPCC (1996 SAR) slowing deforestation and promoting IPCC (1996 SAR) slowing deforestation and promoting reforestation could increase carbon stocks by 60-87PgC 1995-reforestation could increase carbon stocks by 60-87PgC 1995-20502050

IPCC (2000 SRLULUCF) various management options could IPCC (2000 SRLULUCF) various management options could lead to global land-atmosphere flux of -1.3PgC/yr in 2010 and lead to global land-atmosphere flux of -1.3PgC/yr in 2010 and -2.5PgC/yr in 2040-2.5PgC/yr in 2040

Plantations: Plantations: Coniferous AUS & NZ: 10 t/ha/yrConiferous AUS & NZ: 10 t/ha/yr

Coniferous EUR & US: 1.5 - 4.5 t/ha/yrConiferous EUR & US: 1.5 - 4.5 t/ha/yr

Canada and former SU: 0.9 –1.2 t/ha/yrCanada and former SU: 0.9 –1.2 t/ha/yr

Tropical: 6.4 – 10 t/ha/yrTropical: 6.4 – 10 t/ha/yr

BiomassBiomass Litter/woody Litter/woody debrisdebris

Soil Soil Organic Organic MatterMatter

Wood Wood Products Products & & LandfillLandfill

Above Above GroundGround

Below Below GroundGround

Short Short TermTerm

Long Long TermTerm

Cultivated Cultivated landland→ Forest→ Forest

↑↑ ↑↑ -- ↑↑ ↑↑ ↑↑

Non-cultivated Non-cultivated landland→ Forest→ Forest ↑↑ ↑↑ -- ↑↑ ?? ↑↑

IPCC 2000 SRLULUCF, Table 3-6

Repositories for extra carbon storage in terrestrial ecosystemsRepositories for extra carbon storage in terrestrial ecosystems

RepositoryRepository FractionFraction ExamplesExamples Mean Residence Mean Residence Time (MRT)Time (MRT)

BiomassBiomass WoodyWoody

Non-woodyNon-woody

Tree bolesTree boles

Crops/leavesCrops/leaves

Decades to centuriesDecades to centuries

Months to yearsMonths to years

Soil organic Soil organic mattermatter

LitterLitter

Active Active

Stable Stable

Surface litter, crop residuesSurface litter, crop residues

Partially decomposed litter; Partially decomposed litter; carbon in macro-aggregatescarbon in macro-aggregates

Stabilised by clay; Stabilised by clay; chemically recalcitrant chemically recalcitrant carbon; charcoalcarbon; charcoal

Months to yearsMonths to years

Years to decadesYears to decades

Centuries to Centuries to millenniummillennium

ProductsProducts WoodWood

Paper, clothPaper, cloth

grainsgrains

wastewaste

Structural, furnitureStructural, furniture

Paper products, clothingPaper products, clothing

Food and feed grainFood and feed grain

landfilllandfill

Decades to centuriesDecades to centuries

Months to decadesMonths to decades

Weeks to yearsWeeks to years

Months to decadesMonths to decades

Predicted responses to different pools of soil organic matter for Predicted responses to different pools of soil organic matter for agricultural land converted to forest in northeastern United States of agricultural land converted to forest in northeastern United States of

America (Gaudinski et al. 2000, in SRLULUCF)America (Gaudinski et al. 2000, in SRLULUCF)

Carbon sequestration through reforestation Carbon sequestration through reforestation in the tropicsin the tropics

80 year average:

2.36Mg/ha/yr

First 20 years:

6.17 Mg/ha/yr

Silver et al (2000)

Silver et al (2000)

100 year average:

0.41 Mg/ha/yr

First 20 years:

1.30 Mg/ha/yr

Silver et al (2000)

Can sequestration continue beyond 80 years?Can sequestration continue beyond 80 years? One way is to harvest biomass for energyOne way is to harvest biomass for energy The other is to ensure wood products have a long residence timeThe other is to ensure wood products have a long residence time

Paper products like Paper products like packaging, newspapers, packaging, newspapers, magazinesmagazines

0.50.5

Paper products like booksPaper products like books 1515

FurnitureFurniture 2020

Fences, garden products etcFences, garden products etc 2020

Railway sleepers, Railway sleepers, transmission polestransmission poles

4040

Timber in buildingsTimber in buildings 7575

Average estimated lifetime of wooden products [Germany]

Fruewald & Scharai-Rad (2000)

NB The fate of stored carbon in wood products is poorly known

Changing agricultural practices for Changing agricultural practices for below ground carbon storagebelow ground carbon storage

Historical loss of soil C through oxidation~ 50 PgCHistorical loss of soil C through oxidation~ 50 PgC

(Ingram & Fernandes, 2001)(Ingram & Fernandes, 2001)

Average loss of carbon from top 100 cm of soil following conversion to Average loss of carbon from top 100 cm of soil following conversion to agriculture = 15-40%agriculture = 15-40%

Restoration possible through land use change and land managementRestoration possible through land use change and land management

Global potential for C sequestration in agricultural soils 20-30 PgC over 50-Global potential for C sequestration in agricultural soils 20-30 PgC over 50-100 years. (Paustian et al, 1997, cited in Ingram & Fernandes)100 years. (Paustian et al, 1997, cited in Ingram & Fernandes)

Global sequestration from improved management of degraded lands 0.6 – 2 Global sequestration from improved management of degraded lands 0.6 – 2 PgC/yr (Batjes, 1999, cited in Olsson & Ardo, 2002) PgC/yr (Batjes, 1999, cited in Olsson & Ardo, 2002)

Carbon sequestration situation against soil organic carbon level. Source: Ingram & Fernandes (2001)

Main Issues Management OptionsMain Issues Management Options

Soil erosion (especially Soil erosion (especially loss of clay content)loss of clay content)

Oxidation of carbonOxidation of carbon TillageTillage Temperature (e.g. Temperature (e.g.

reduced canopy)reduced canopy) Removal of organic Removal of organic

residuesresidues Drainage (aeration)Drainage (aeration)

No tillage No tillage Change of crops (raise Change of crops (raise

NPP)NPP) FertiliserFertiliser Land use change – Land use change –

agroforestry, grasslandagroforestry, grassland Fallow with Fallow with

grasses/legumesgrasses/legumes Grazing of rangelands (see Grazing of rangelands (see

Schuman et al, 2002)Schuman et al, 2002)

Olsson & Ardo (2002) case study from SudanOlsson & Ardo (2002) case study from Sudan

Modelling of 6 different management systems in Modelling of 6 different management systems in Sudanese cropland Sudanese cropland

SystemSystem Soil carbon in 2100 Soil carbon in 2100 (gC m(gC m-2-2))

No changeNo change 7070

5:6 crop: fallow5:6 crop: fallow 115115

5:10 crop: fallow5:10 crop: fallow 128128

5:15 crop: fallow5:15 crop: fallow 163163

5:20 crop: fallow5:20 crop: fallow 170170

Grazing onlyGrazing only 245245

Institutional BasisInstitutional Basis Kyoto article 3 “removals by sinks resulting from direct human-induced Kyoto article 3 “removals by sinks resulting from direct human-induced

land-use change and forestry activities, limited to afforestation, land-use change and forestry activities, limited to afforestation, reforestation and deforestation since 1990, measured as verifiable changes reforestation and deforestation since 1990, measured as verifiable changes in carbon stocks in each commitment period, shall be used to meet the in carbon stocks in each commitment period, shall be used to meet the commitments under this Article….”commitments under this Article….”

Other sinks (such as agricultural soils may be included in the future)Other sinks (such as agricultural soils may be included in the future) 66thth COP (resumed July 2001) agreement that reforestation and afforestation COP (resumed July 2001) agreement that reforestation and afforestation

allowed under Clean Development Mechanism.allowed under Clean Development Mechanism. CDM – allows developed countries to meet their own commitments by CDM – allows developed countries to meet their own commitments by

funding emission reduction or carbon sequestration projects in developing funding emission reduction or carbon sequestration projects in developing countries.countries.

Limited to 1% of a country’s baseline emissions (i.e. can meet about 20% Limited to 1% of a country’s baseline emissions (i.e. can meet about 20% of their reduction through CDM forestry projects).of their reduction through CDM forestry projects).

Eligible Land Use Activities in the CDM. Source: IIED 2002

Sequestration: a few concernsSequestration: a few concerns

Verification issues and transaction costsVerification issues and transaction costs What kind of forestry?What kind of forestry?

Large-scale?Large-scale? MonoculturesMonocultures Fast-growing exotics?Fast-growing exotics?

Whose development priorities?Whose development priorities? Will sinks solve the problem?Will sinks solve the problem? Global feedbacksGlobal feedbacks

FAO (2001) Global Forest Resources Assessment 2000, FAO (2001) Global Forest Resources Assessment 2000, www.fao.org/forestry/fo/fra/main/index.jspwww.fao.org/forestry/fo/fra/main/index.jsp Fruehwald, A. & Scharai-Rad (2000) Wood products as carbon sinks: a methodological approach,Fruehwald, A. & Scharai-Rad (2000) Wood products as carbon sinks: a methodological approach,

www.bib.fsagx.ac.be/coste21/ftp/2001-04-26/sharai-rad-sum.pdfwww.bib.fsagx.ac.be/coste21/ftp/2001-04-26/sharai-rad-sum.pdf IPCC (2001) Climate Change 2001: the scientific basis. IPCC (2001) Climate Change 2001: the scientific basis. www.grida.no/climate/ipccwww.grida.no/climate/ipcc IPCC (2000) Special Report on Land Use, Land Use Change and ForestryIPCC (2000) Special Report on Land Use, Land Use Change and Forestry IPCC (2001) IPCC (2001) Climate Change 2001: MitigationClimate Change 2001: Mitigation. Section 4. Technological and Economic Potential of . Section 4. Technological and Economic Potential of

Options to Enhance, Maintain, and Manage Biological Carbon Reservoirs and Geo-engineering.Options to Enhance, Maintain, and Manage Biological Carbon Reservoirs and Geo-engineering. IIED (2002) IIED (2002) Laying the Foundations for Clean Development: preparing the land use sector: a quick Laying the Foundations for Clean Development: preparing the land use sector: a quick

guide to the Clean Development Mechanismguide to the Clean Development Mechanism, London: International Institute for Environment and , London: International Institute for Environment and Development, Development, www.cdmcapacity.orgwww.cdmcapacity.org

Ingram, J. & Fernandes, E. (2001) Managing carbon sequestration in soils: concepts and terminology, Ingram, J. & Fernandes, E. (2001) Managing carbon sequestration in soils: concepts and terminology, Agriculture, Ecosystems and Environment, Agriculture, Ecosystems and Environment, 87, 111-117.87, 111-117.

Schuman, G., Janzen, H. & Herrick, J. (2002) Soil carbon dynamics and potential carbon sequestration Schuman, G., Janzen, H. & Herrick, J. (2002) Soil carbon dynamics and potential carbon sequestration by rangelands, by rangelands, Environmental PollutionEnvironmental Pollution, 116, 391-396, 116, 391-396

Silver, W., Ostertag, R. & Lugo, A. (2000) The potential for carbon sequestration through reforestation Silver, W., Ostertag, R. & Lugo, A. (2000) The potential for carbon sequestration through reforestation of abandoned tropical agricultural and pasture lands, of abandoned tropical agricultural and pasture lands, restoration Ecology, restoration Ecology, 8 (4), 394-407.8 (4), 394-407.

Olsson, L. & Ardo, J. (2002) Soil carbon sequestration in degraded semiarid agro-ecosystems – perils Olsson, L. & Ardo, J. (2002) Soil carbon sequestration in degraded semiarid agro-ecosystems – perils and potentials, and potentials, Ambio Ambio 30 (6), 471-477.30 (6), 471-477.

Seely, B., Welham, C., Kimmins, H. (2002) ‘Carbon sequestration in a boreal forest ecosystem: results Seely, B., Welham, C., Kimmins, H. (2002) ‘Carbon sequestration in a boreal forest ecosystem: results from the ecosystem simulation model, FORECAST’, from the ecosystem simulation model, FORECAST’, Forest Ecology and Management Forest Ecology and Management 169, 123-135169, 123-135

Ridgwell, A., Maslin, M. & Watson, A. (2002) Reduced effectiveness of terrestrial carbon Ridgwell, A., Maslin, M. & Watson, A. (2002) Reduced effectiveness of terrestrial carbon sequestration due to an antagonistic response of ocean productivity, sequestration due to an antagonistic response of ocean productivity, Geophysical Research LettersGeophysical Research Letters, 29 , 29 (6), 19(6), 19