Spatial Distribution of Selenium and Other Inorganic Constituents in Ground WaterUnderlying a Drained Agricultural Field, Western San Joaquin Valley, California. Regional Aquifer-System Analysis

摘要

High concentrations of selenium in subsurface agricultural drainwater in thewestern San Joaquin Valley, California, have caused high mortality rates in waterfowl at Kesterson National Wildlife Refuge near Gustine, California. Agricultural drainage systems were installed in some low-lying areas of the western San Joaquin Valley to prevent accumulation of soil root-zone salt that adversely affects crop production. Shallow ground water affects about 100,000 ha of agricultural land in the western San Joaquin Valley. High concentrations of boron, molybdenum, and arsenic in drainwater and ground water are also of primary environmental concern because of documented or possible adverse effects on water quality, public health, agricultural productivity, and fish and wildlife.