abstract- a detailed understanding of crop rooting systems will facilitate water use reduction, optimized nutrient uptake and irrigation scheduling more efficiently. a field experiment was conducted during 2005-2006 to investigate sugar beet rooting depth growth, irrigated with three irrigation methods (subsurface drip, surface drip and furrow) and two water qualities (recycled wastewater: ec= ...

A computer model was created as a scientific and management tool for understanding the effects of macrophytes on hydrodynamics and water quality. A model was required that could simulate macrophytes in a complex water body and could be coupled to a multicompartment water quality model of phytoplankton, dissolved oxygen, nutrients, pH, and organic matter. This would permit the investigation of w...

A 155,947 ha portion of the Shenango River watershed in western Pennsylvania was evaluated as to the potential impact of agriculture drainage on water quality. Approximately a third of the area is being used as either cropland or pasture with approximately an equal percentage in forest lands. Eleven subwatersheds were evaluated as to their potential for nonpoint source pollution according to th...

Lack of monitoring and implementation of appropriate management practices and strategies in compliance with the Ramsar Convention obligations have been contributing to severe degradation of Beeshazar Lake, a Ramsar site in central Nepal. The surface water quality and characteristics of underlying sediments were studied to determine the limnological status of the lake. Water quality in Beeshazar...

This report evaluates and demonstrates technical methods of comparing point source (PS) and non-point source (NPS) nutrient discharges that can be used for developing credit scoring methods for a water quality trading system. We evaluate the state of the science for evaluating hydrologic functions within watersheds and for linking those physical functions to water quality and environmental outc...

Historically, phosphorus has been considered to be the primary nutrient limiting phytoplankton growth in freshwater ecosystems. We tested this hypothesis in 19 Kansas reservoirs located within the Central Plains region, USA. Bioassay experiments were conducted to assess growth-rate limitation by nitrogen (N), phosphorus (P) and nitrogen and phosphorus (N and P). The addition of P alone rarely i...

Current paradigms of reservoir ontogeny suggest that water-level fluctuations may increase sedimentary nutrient release, causing long-term eutrophication of water bodies formed by dryland flooding. Less is known of the changes in nutrient status following conversion of natural lakes into reservoirs. Here, we use historical hydrological and limnological data and paleolimnological records of sedi...