We report here on the extension of Passive Flux Meter (PFM) applications for measuring fluxes of oxyanions in groundwater, and present results for laboratory and field studies. Granular activated carbon, with and without impregnated silver (GAC and SI-GAC, respectively), was modified with a cationic surfactant, hexadecyltrimethylammonium (HDTMA), to enhance the anion exchange capacity (AEC). La...

The Ogallala Aquifer is an important source of irrigation water on the Texas High plains; however, significant decreases in saturated thickness threaten its future use for irrigation. A better understanding of the roles of playas, ephemeral surface ponds, in aquifer recharge is needed to establish levels of withdrawals that will meet either established desired future conditions or sustainabilit...

Accurate estimates of groundwater recharge are essential for effective management of groundwater, especially when supplies are limited such as in many arid and semiarid areas. In the Hebei Plain, China, water shortage is increasingly restricting socioeconomic development, especially for agriculture, which heavily relies on groundwater. Human activities have greatly changed groundwater recharge ...

Pakistan’s Irrigation system is more than a century old, the distribution system within any canal command is designed to distribute the canal water equitably ignoring rainfall patterns and underlying groundwater resources. Now, the groundwater contribution in meeting crop water requirement has even crossed the canal water supply in the existing scenario of increased cropping intensities. The un...

This Licentiate Thesis presents a new approach of understanding leakage in agricultural land. Former studies concentrate on long term measurement of different pollutants in nearby watercourses and streams. The new approach is so far only numerically performed, but will soon be complemented by laboratory tests and field measurements. Our hypothesis is that nutrient leakage into groundwater is ca...

Dune slacks are seasonal wetlands, high in biodiversity, which experience considerable within-year and between-year variations in water-table. They are subject to many pressures including climate change, land use change and eutrophication. Despite their biological importance and the threats facing them, the hydrological and nutrient parameters that influence their soil properties and biodiversi...

Groundwater flow in sedimentary rock saprolite, and in soils derived from this material, is strongly influenced by sedimentary layering and fractures inherited from the parent bedrock. The main objectives of this study were to determine whether parent bedrock lithology and infilling of fractures and other macropores with pedogenically derived clays and Fe/Mn oxides also play major roles in cont...

lysimeter tests were conducted on shallow groundwater that supplies part of the maize water requirements to determine crop yield. twenty-four 0.8 m diameter lysimeters were buried in the test field at a depth of 1.2 m. the lysimeters were filled with the field soil (silty loam) and planted with summer maize. the groundwater depth in the lysimeters was set at 0.6 m using marriotte bottles. three...

Nitrate concentrations of groundwater are increasing in residential areas. One probable cause is input of nitrogen fertilizers to maintain healthy turfgrass. This study was conducted to evaluate differences in nitrate concentrations in soil water between sites fertilized with chemical or organic fertilizer. To obtain nitrate concentrations leaching below turfgrass and evaluate the impact to gro...