Hillslope and Climatic Controls on Hydrologic Fluxes

摘要: The position and shape of the hillslope water table has long been considered to be a useful diagnostic both for field analysis spatial structure hydrologic behavior initializing forecasting models. Water positions near surface often indicate areas which contribute runoff generation, yield evaporation at climate-demanded rate, produce net discharge saturated zone groundwater. Deeper tables typically drier where is suppressed infiltration enhanced, therefore promoting groundwater recharge. time integral these fluxes over an area forms local climatic cycle. Continuity (throughout hillslope) modeled long-term mean moisture land-atmosphere interface within unsaturated zones provides closure climate-hillslope system, it used determine equilibrium corresponding recharge, discharge, evaporation, production. This method tool systematic study how characteristics atmospheric forcing (e.g., precipitation, evaporative demand, storm intermittency intensity), soil properties, geologic features topography) interact observed patterns distinct various scales. Application methodology simplified idealized geometries reveals in good qualitative agreement with observations. Case studies demonstrate that wide range nature reproducible climatic, geologic, parameters. Partial full system yields few dimensional parameter groups, relative values are indicative transitions between geologic-, soil-, climate-controlled conditions presence or absence characteristic such as seepage faces, recharge areas, hinges, midline zones, partial Under limited lateral transmissivity slope, region (over exchange zero) can dominate lead invariance area-averaged respect length scale.