Net infiltration of the Death Valley regional ground-water flow system, Nevada and California

Recharge in the Death Valley regional ground-water flow system (DVRFS) was estimated from net infiltration simulated by Hevesi and others (2003) using a deterministic mass-balance method. Hevesi and others (2003) estimated potential recharge for the DVRFS, an approximately 100,000 square-kilometer region of southern Nevada and California, using the net-infiltration model, INFILv3. Net infiltration, estimated on a cell-by-cell basis, equaled the sum of snowmelt, precipitation, and infiltrating surface flow minus the sum of evapotranspiration (ET), runoff, and changes in root-zone storage. The net-infiltration model was calibrated to available surface-water flow measurements and constrained by prior estimates of recharge and discharge. The calibrated net-infiltration model (model 1 in Hevesi and others, 2003) was used to simulate daily net infiltration from 1950 through 1999 across the DVRFS model domain (San Juan and others, 2004) and was also used as a component of recharge in the DVRFS transient ground-water flow model (Faunt and others, 2004). The DVRFS transient ground-water flow model is one of the most recent in a number of regional-scale models developed by the U.S. Geological Survey (USGS) for the U.S. Department of Energy (DOE) to support investigations at the Nevada Test Site (NTS) and at Yucca Mountain, Nevada (see "Larger Work Citation", Chapter A, page 8).

死亡谷区域地下水流动系统（Death Valley Regional Ground-water Flow System, DVRFS）的补给量，通过Hevesi等（2003）采用确定性质量平衡法模拟得到的净入渗量进行估算。Hevesi等（2003）借助净入渗模型INFILv3，对面积约10万平方千米、涵盖内华达州南部与加利福尼亚州部分区域的DVRFS的潜在补给量进行了估算。净入渗量以逐网格单元进行估算，其值为融雪量、降水量与入渗地表径流量之和，减去蒸散发（Evapotranspiration, ET）、地表径流量以及根区储水量变化量之和。该净入渗模型基于已有的地表径流量实测数据进行校准，并以既往的补给与排泄估算结果作为约束条件。经校准的净入渗模型（即Hevesi等（2003）中的模型1）被用于模拟1950年至1999年间DVRFS模型域内的逐日净入渗量（San Juan等，2004），同时也作为补给量组成部分被纳入DVRFS瞬态地下水流动模型（Faunt等，2004）。DVRFS瞬态地下水流动模型是美国地质调查局（U.S. Geological Survey, USGS）为美国能源部（U.S. Department of Energy, DOE）开发的一系列区域尺度模型中的最新模型之一，旨在支持内华达试验场（Nevada Test Site, NTS）与内华达州尤卡山的相关调查研究（详见"Larger Work Citation"，A章节，第8页）