Large plate lysimeter leachate collection efficiency for water beingtransported from soil to ground water

摘要

A large, zero-tension, plate lysimeter (3.05 x 2.13 m) was installed to intercept percolating soil water at Bikini Atoll (11 [degrees] 35'N, 165[degrees] 25'E), a former nuclear test-site. The purpose of the very large plate size was to increase the water collection efficiency of the lysimeter, thus providing larger volumes of water per cm of rainfall to measure the concentration of various radionuclides. In two experiments, controlled amounts of irrigation water were applied over the lysimeter and leachate water was collected. Evapotranspiration calculations were made using the Penman-Monteith equation and climate data collected at the atoll. The water balance efficiency of the lysimeter was essentially 100%, in contrast to low efficiencies (10-50%) reported for smaller plate lysimeters.