Vegetation Functional Properties Determine Uncertainty of Simulated Ecosystem Productivity: A Traceability Analysis in the East Asian Monsoon Region

E. Cui, K. Huang, M.A. Arain, J.B. Fisher, D.N. Huntzinger, A. Ito, Y. Luo, A.K. Jain, J. Mao, A.M. Michalak, S. Niu, N.C. Parazoo, C. Peng, S. Peng, B. Poulter, D.M. Ricciuto, K.M. Schaefer, C.R. Schwalm, X. Shi, H. Tian, W. Wang, J. Wang, Y. Wei, E. Yan, L. Yan, N. Zeng, Q. Zhu and J. Xia


SUMMARY

The ability of Earth system models to project climate change is limited by how well they estimate terrestrial ecosystems’ ability to sequester carbon. The East Asian monsoon region is highly productive, but there have not been extensive systematic evaluations of how well current terrestrial biosphere models estimate this region's ability to take up carbon. This work develops a traceability framework to evaluate how well gross primary productivity (the rate of atmospheric carbon dioxide uptake by plants via photosynthesis) is simulated by models for the East Asian monsoon region. We found that the ways in which models represented vegetation functional properties such as carbon use efficiency, carbon turnover time, among others, were the main sources of variations in how models estimated the East Asian monsoon region's ability to sequester carbon. This study highlights the need for a better understanding of variations in plant traits and vegetation functional properties so that differences in the initial conditions for current terrestrial biosphere models can be resolved.

 

Figure: Schematic diagram of the GPP-traceability framework introduced in the study. CUE, carbon-use efficiency; τveg, vegetation carbon turnover time; Fleaf leaf carbon fraction; SLA, specific leaf area; PLAI, LAI‐level photosynthesis. GPP gross primary productivity; LAI, leaf area index; NPP, net primary productivity. 

Cui, E., K. Huang, M.A. Arain, J.B. Fisher, D.N. Huntzinger, A. Ito, Y. Luo, A.K. Jain, J. Mao, A.M. Michalak, S. Niu, N.C. Parazoo, C. Peng, S. Peng, B. Poulter, D.M. Ricciuto, K.M. Schaefer, C.R. Schwalm, X. Shi, H. Tian, W. Wang, J. Wang, Y. Wei, E. Yan, L. Yan, N. Zeng, Q. Zhu, J. Xia (2019) "Vegetation Functional Properties Determine Uncertainty of Simulated Ecosystem Productivity: A Traceability Analysis in the East Asian Monsoon Region," Global Biogeochemical Cycles, 33 (6), 668-689, doi:10.1029/2018GB005909.