HR: 1340h
AN: B53B-1188    [Abstracts]
TI: Evaluation of the LPJ-DGVM for modelling tropical ecosystem processes in the Amazon Basin
AU: * Poulter, B
EM: ben.poulter@pik-potsdam.de
AU: Cramer, W
EM: wolfgang.cramer@pik-potsdam.de
AU: Heyder, U
EM: ursula.heyder@pik-potsdam.de
AB: Dynamic global vegetation models (DGVM) provide spatially continuous information for carbon and water fluxes and vegetation distribution. In tropical regions, DGVMs are necessary to resolve large-scale questions related to carbon cycling and disturbance and for evaluating field-based data from eddy covariance or biomass measurements. We evaluate the sensitivity of these parameters in the LPJ-DVM by comparing biomass, plant functional type distribution (PFT), and carbon fluxes against field and remote sensing observations. Based on literature review, we adjusted the range of rooting distributions, sapwood to heartwood turnover rates, and the development of phenology (leaf longevity and response to drought) within LPJ. We found that rooting distributions were most sensitive in the southern and eastern Amazon where water is more frequently limiting. Carbon allocation and phenology were most sensitive in the wetter regions of the Amazon and strongly influenced the competitiveness and biogeography of PFTs. The optimal distribution of parameters is likely more variable than the number of PFTs in use; this suggests that dynamic sub-modules rather than fitted parameters may be required for determining rooting and phenology patterns.
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting