Vegetation regulation on streamflow intra‐annual variability through adaption to climate variations. Issue 23 (2nd December 2015) - Ye, Sheng
Abstract: This study aims to provide a mechanistic explanation of the empirical patterns of streamflow intra‐annual variability revealed by watershed‐scale hydrological data across the contiguous United States. A mathematical extension of the Budyko formula with explicit account for the soil moisture storage change is used to show that, in catchments with a strong seasonal coupling between precipitation and potential evaporation, climate aridity has a dominant control on intra‐annual streamflow variability. But in other catchments, additional factors related to soil water storage change also have important controls on how precipitation seasonality propagates to streamflow. More importantly, use of leaf area index as a direct and indirect indicator of the above ground biomass and plant root system, respectively, reveals the vital role of vegetation in regulating soil moisture storage and hence streamflow intra‐annual variability under different climate conditions. Key Points: Ratio between seasonal variability of precipitation and streamflow decomposed under Budyko framework Control of climate aridity, seasonality in precip, and its coupling with ET on catchment responses Vegetation plays an important role when the climate seasonality is weak