Improving the representation of large carbon pools in ecosystem models Mat Williams (Edinburgh...
-
Upload
dulcie-shields -
Category
Documents
-
view
218 -
download
0
Transcript of Improving the representation of large carbon pools in ecosystem models Mat Williams (Edinburgh...
Improving the representation of large carbon pools in ecosystem models
Mat Williams (Edinburgh University)
John Grace (Edinburgh University)
Andreas Heinemeyer (York University)
Phil Ineson (York University)
Theresa MeachamGetty Images
Introduction:
Forests buffer the rate of atmospheric CO2 increase.
• Woody biomass carbon ~ 580 Mt.• Soil carbon stock (to 0.8M) ~1200 Mt.
• UK emissions 654Mt CO2 (2006).
• PhD scope: • Link soil scientists and plant biologists.• Link long time series measurements of
soil, canopy and forest growth.
www.noaa.gov
LULUCF (2006)
1. Features of forest large carbon pools
2. The uncertainties surrounding large carbon pools
3. The direction of my research.
Talk outline:
Oak Woodland: Getty Images
Forest carbon sequestration:
AtmospherePhotosynthesis
Root
Foliage
Wood
Fungi Soil
Fungal respiration
Plant respiration
Microbial respiration
Fast carbon fluxes:
View from flux tower: Harwood forest
Atmosphere-canopy interactions
Fast carbon fluxes:
Current photosynthesis drives soil respiration.
Hogberg, P., A. Nordgren, et al. (2001). "Large-scale forest girdling shows that current photosynthesis drives soil respiration." Nature 411(6839): 789-792.
Calculated fungal respiration
Calculated root respiration
Hogberg et al (2001)
Slow carbon fluxes:
Soil carbon fluxes
Arctopussy at Alice Holt
Woody Biomass
Getty Images
Uncertainties surrounding large carbon pools:
Below ground carbon fluxes are poorly understood.
Heinemeyer, A., I. P. Hartley, et al. (2007). "Forest soil CO2 flux: uncovering the contribution and environmental responses of ectomycorrhizas." Global Change Biology 13(8): 1786-1797.
Heinemeyer et al (2007)
Uncertainties surrounding large carbon pools:
Magnani, F., M. Mencuccini, et al. (2007). "The human footprint in the carbon cycle of temperate and boreal forests." Nature
CO2 fluxes change as a forest ages.
Magnani et al (2007)
1. Above ground processes influence below ground carbon pools.
Leaf fall
Bud burstBud burst
Soil CO2 efflux
(CO2 m-1 s-1)
March June Sep Dec March June
Adapted from Heinemeyer (2008)
1
2
3
4
5
The Direction of my research:
1. Above ground processes influence below ground carbon pools. Phenology measurements
MODIS Images:
Monks Wood, Cambridge. Courtesy of University of Southampton
Courtesy of Mat Disney, NERC, CTCD
Hemispherical photographs:
The Direction of my research:
2. Error within ecosystem models is lowest at mid-rotation
NEP
(t C ha-1 y-1)
Age (Years)
1. Disturbance recovery in young stands.
2. Patchy carbon allocation in old stands.
3. Root :Leaf Area change with age.
The Direction of my research:
0
3. Root optimality theory should be incorporated within ecosystem models
Water Nutrients
CO2 Factors affecting the economics of carbon allocation:
•Stand age
•Competitive interactions
•Environmental factors
•Stand genetics
Leaves
Stems
Roots
The Direction of my research:
4. Use models to inform UK forest policy
Getty Images
Woodland policy aims in England:
• Ensure woodlands are resilient to impact of climate change.
• Protect and enhance environmental resources of soil, water and biodiversity.
• Improve competitiveness of woodland businesses, such as woodland products and reduction of carbon emissions.
‘A Strategy for England’s Trees, Woods and Forests’, Defra (2007)
The Direction of my research:
The Direction of my research:
Summary:
Large carbon pools sequester atmospheric carbon. Long time series data, modelling and earth observation techniques
may aid our understanding of processes. Model outputs can help make future predictions and inform policy.
Harwood Forest; Courtesy of Mat Disney, CTCD
Thank You
Any Questions?
The Direction of my research:
Griffin Forest
Wheldrake Forest
Alice Holt
•UK Field sites
•CarboAge project
•Michigan biological station
Harwood Forest