A Common Stomatal Parameter Set Used to Simulate the Energy and Water Balance over Boreal and Temperate Forests

A parameter set expressing the potential response used to simulate evapotranspiration was inferred from pooled data of leaf-level stomatal conductance in the Far East. We used Jarvis-type parameterization, which consists of restriction terms of light, air dryness, temperature, and soil water. Two parameter sets, pooled common (PC) and within-site (WS) sets, were determined using stomatal conductance data of eight species at nine sites. Seasonal changes of energy and water fluxes observed at four tower sites are well reproduced by a land surface model, despite using a different set of parameters. The results suggest that energy and water fluxes can be simulated using only one common parameter set with no parameter tuning, at least for forests in a wide region of the Far East. We discuss why similar fluxes were simulated using PC and WS parameters despite the clear differences between these two parameter sets. Sensitivity experiments showed that the effects of maximum stomatal conductance and soil water content mutually cancel each other in Yakutsk and that an optimum temperature effect was added.