[A-CG34_1PM1] Integrated studies for Interactions between Land-Ecological, Hydrological, and Atmospheric processes

[ACG34-05] Impacts of representation of stomatal conductance on vegetation distribution and functions under changing climate

*Hisashi SATO¹, Tomo'omi KUMAGAI², Gabriel KATUL³ (1.RIGC, JAMSTEC, 2.HyARC, Nagoya University, 3.Duke University)

Keywords:Stomatal Conductance, Hydrological Cycle, Carbon Cycle, Dynamic Global Vegetation Models, Global Warming, Africa

Stomata reponce is under control of light intensity, CO2 concentration, vapor pressure deficit, leaf water potential. For describing stomatal responses to such environmental factors, several empirical and semi-empirical models have been developed. How these models response to the changing environmental is an important issue, because between 80% and 90% of the total evapotranspiration from the land surface is caused by transpiration, and the process consumes almost half of the solar energy absorbed by the ground (Jasechko et al. 2013). Here, we examined how representation of stomatal conductance pose impact on the forecast of geographical distribution of vegetation and its functions (i.e. carbon and water fluxes) under the forecasted climatic condition during the 21st century. We studied the African continent, because Africa is a useful target for assessing changes in vegetation due to climate change. The distribution of African vegetation is primarily regulated by soil moisture availability and thus is tightly coupled with climatic variability. For our study, we employed a dynamic vegetation model SEIB-DGVM. Our previous study shows that the model reproduced geographical distributions of the continent's biomes, annual gross primary productivity (GPP), and biomass over the African continent under current climatic conditions (Sato et al. 2012).ReferencesJasechko S, Sharp ZD, Gibson JJ, Birks SJ, Yi Y & Fawcett PJ (2013) Terrestrial water fluxes dominated by transpiration. Nature 496.Kumagai, T., Katul, G. G., Porporato, A., Saitoh, T. M., Ohashi, M., Ichie, T. and Suzuki, M. (2004) Carbon and water cycling in a Bornean tropical rainforest under current and future climate scenarios. Advances in Water Resources, 27(12), P1135-1150.Sato H & Ise T (2012) Effect of plant dynamic processes on African vegetation responses to climate change: Analysis using the spatially explicit individual-based dynamic global vegetation model (SEIB-DGVM). Journal of Geophysical Research-Biogeosciences 117.