ON THE IMPORTANCE OF INCLUDING VEGETATION DYNAMICS IN HYDROLOGICAL SIMULATION

摘要

Vegetation exerts effects on runoff via features such as interception, stomatal behavior and transpiration, and rooting strategy. Therefore, it is essential to consider the dynamic role of vegetation e.g. physiological processes, phenological processes, and vegetation changes in runoff simulation. However, the parameterization of vegetation as a dynamic component is insufficient in stand-alone hydrological models. This paper evaluates and improves the hydrological performance of Lund-Postdam-Jena model (LPJ), a prominent dynamic global vegetation model considering transient structural changes in major vegetation types. Applications to four basins located in different climatic zones show that the modified LPJ simulated runoff and vegetation well. Additionally, to evaluate effects of vegetation on runoff and show the potential advantages of LPJ over stand-alone hydrological models, as an example, the model was run under a scenario of changing atmospheric CO_2 content alone and the results showed that runoff increased in humid basins while decreased in arid basins.