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Carbon and forest management. Robert Matthews Forest Research Biometrics, Surveys and Statistics Division Alice Holt Research Station, Farnham. The problem. Human activity is interfering with the global carbon balance This is leading to climate change The major causes are:
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Carbon and forest management Robert Matthews Forest Research Biometrics, Surveys and Statistics Division Alice Holt Research Station, Farnham
The problem • Human activity is interfering with the global carbon balance • This is leading to climate change • The major causes are: • Burning fossil fuels • Deforestation.
3.0 GtC y -1 6.3 GtC y -1 1.6 GtC y -1 1.7 GtC y -1 Burning fossil fuels Ocean absorption Land-use change (including deforestation) ‘Enhanced’ vegetation growth Global carbon balance c. 1990-2000 Net accumulation: 3.2 GtC y -1
Offsetting CO2 emissions by planting trees Permanence Saturation It works Additionality
Model-based evaluation - C-flow Atmospheric CO2 Photosynthesis (NPP) (from volume growth curve & expansion factors) Stem thinning Woody biomass Non-woody biomass Wood products Product decay and harvesting Natural mortality Thinnings Harvest debris Woody litter Non-woody litter Non-woody litter decay Woody litter decay Transfer of residues to soil Soil organic matter Soil decomposition
Wood products in use Wood products in landfill Tree roots Non-forest trees Forest tree stems and branches Forest soils Roughly 100 MtC UK forest carbon stocks
Model-based evaluation - CARBINE Thin and fell ‘Carbon reserve’ ‘Energy forestry’ ‘Continuous cover’
20% 6% Forest carbon management potential +Forest sector management Forest carbon sequestration 2% 5% UK 0.15 GtC y-1) 20% with imports? 45% >100% World (25 GtC y-1) World (3.2 GtC y-1)
Conclusions (global) • Globally, forests play an important part in the carbon balance. • Forests are also a renewable resource. • Options for mitigating climate change are: • Afforestation • Reforestation • Adjustments to forest management • Avoided deforestation • Targeted timber utilistation.
Conclusions (UK) • UK forests can make a small but useful contribution. • Carbon sequestration can be ‘hostage to fortune’. • Emissions saved through (home grown or imported) wood are ‘banked’. • Focus on use of wood at least as much as forest management. • Role for imported wood?