Nonpoint source nitrogen is recognized as a significant water pollutant worldwide. One of the major contributors is agricultural drainage line water. A potential method of reducing this nitrogen discharge to water bodies is the use of immobilized denitrifying sludge (IDS). Our objectives were to (1) produce an effective IDS, (2) determine the IDS reaction kinetics in laboratory column bioreacto...

There are concerns about the impact of maize cultivation with high applications of nitrogen (N) and phosphorus (P) on water quality in surface waters in Mediterranean Central Chile. This study estimated the contribution of N and P from maize fields to nearby drainage channels and evaluated the effects in water quality. An N and P budget was drawn up for three fields managed with a maize-fallow ...

The Midwestern United States is dominated by agricultural production with high concentrations of swine, leading to application of swine manure onto lands with artificial subsurface drainage. Previous reports have indicated elevated levels of antibiotic resistance genes (ARGs) in surface water and groundwater around confined animal feeding operations which administer antimicrobials. While previo...

Irrigation water is limiting for crop production in arid and semi-arid areas. Furthermore, excess nitrogen (N) application is a source of groundwater contamination. Partial root drying irrigation (PRD) can be used as water saving technique and a controlling measure of groundwater N contamination. The objectives of this investigation were to evaluate the effect of ordinary furrow irrigation (OFI...

The dramatic effect of flow through macropores and hardpan fissures on artificial drainage in shallow sloping soils is demonstrated. Implications of these preferential flow mechanisms on drainage design and water management are discussed. In designing drainage systems on these types of soils, more emphasis should be given to the characteristics of the hardpan.

Modeling landscape with high-resolution digital elevation data (DEM) in a geographic information system can provide essential morphological and structural information for modeling surface processes such as geomorphologic process and water systems. This paper introduces several DEM-based spatial analysis processes applied to characterize spatial distribution and interactions of ground and surfac...

Implementation of artificial subsurface drainage (tile drainage) for cultivation of row crops in poorly-drained areas of the Upper Midwest of the United States has enabled the region to be one of the most agriculturally productive areas of the world; but has also resulted in loss of wetland ecosystems, altered hydrology, and increased transport of nitrate-nitrogen (NO3-N) to surface water. The ...

In the irrigated western U.S. disposal of drainage water has become a significant economic and environmental liability. Development of irrigation water management practices that reduce drainage water volumes is essential. One strategy combines restricted drainage outflow (by plugging the drains) with deficit irrigation to maximize shallow groundwater consumption by crops, thus reducing drainage...

Wadi El Raiyan is a great depression located southwest of Cairo in the Western Desert of Egypt. Lake Qarun, located north of the study area, is a closed basin with a high evaporation rate. The source of water in the lake is agricultural and municipal drainage from the El Faiyum province. In 1973, Wadi El Raiyan was connected with the agricultural wastewater drainage system of the Faiyum provinc...

iran is ranked fourth for saline-sodic soils in asia following china, india and pakistan. therefore, if coupled with waterlogging, drainage would be an inevitable and indispensable activity agriculture in most irrigated parts of iran. drain installation depth is one of the main economic as well as environmental challenges in design and construction of drainage systems. deep pipe drain installat...