Experimental studies in natural groundwater recharge dynamics: Assessment of recent advances in instrumentation

M. Sophocleous; C. A. Perry

doi:10.1016/0022-1694(84)90133-1

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Experimental studies in natural groundwater recharge dynamics: Assessment of recent advances in instrumentation

M. Sophocleous·C. A. Perry

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Abstract

To quantify and model the natural groundwater-recharge process, two sites in south-central Kansas, U.S.A., were instrumented with various modern sensors and data microloggers. The atmospheric-boundary layer and the unsaturated and saturated soil zones were monitored as a unified regime. Data from the various sensors were collected using microloggers in combination with magnetic-cassette tape, graphical and digital recorders, analog paper-tape recorders, and direct observations to evaluate and automate data collection and processing. Atmospheric sensors included an anemometer, a tipping-bucket raingage, an air-temperature thermistor, a relative-humidity probe, a net radiometer, and a barometric-pressure transducer. Sensors in the unsaturated zone consisted of soil-temperature thermocouples, tensiometers coupled with pressure transducers and dial gages, gypsum blocks, and a neutron moisture probe operated by an observer. The saturated-zone sensors consisted of a water-level pressure transducer, a conventional float gage connected to a variable potentiometer, soil thermocouples, and a number of multiple-depth piezometers. Evaluation of the operation of these sensors and recorders indicated that certain types of equipment such as pressure transducers are very sensitive to environmental conditions. Extraordinary steps had to be taken to protect some of the equipment, whereas other equipment seemed to be reliable under all conditions. Based on such experiences, a number of suggestions aimed at improving such investigations are outlined.

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Journal of Hydrology Article

Source-reported bounding extent: 37.64917420455242° to 38.507940104645996° latitude; -99.1748871630371° to -97.68600447634276° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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M. Sophocleous, C. A. Perry. 1984. Experimental studies in natural groundwater recharge dynamics: Assessment of recent advances in instrumentation. https://doi.org/10.1016/0022-1694(84)90133-1

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