The quaternary aquifer of Vitoria-Gasteiz (Basque Country, Northern Spain) is characterised by a shallow water table mainly fed by drainage water, and thus constitutes a vulnerable zone in regards to nitrate pollution. Field studies were performed with a potato crop in 1993 and a sugar beet crop in 2002 to evaluate their impact on nitrate leaching. The overall predictive quality of the STICS so...

At the European scale, nitrate concentration is the most important parameter that determines groundwater quality. Since in most cases nitrate input into the aquifer is a non-point source pollution problem, measures to reduce nitrate leaching have to be designed on the aquifer scale. In this context we have coupled the unsaturated, vertical soil water and nitrogen transport model SIMWASER/STOTRA...

Nitrate nitrogen losses through subsurface drainage and crop yield are determined by multiple climatic and management variables. The combined and interactive effects of these variables, however, are poorly understood. Our objective is to predict crop yield, nitrate concentration, drainage volume, and nitrate loss in subsurface drainage from a corn (Zea mays L.) and soybean (Glycine max (L.) Mer...

Wintering cattle directly in the field creates potential concerns with water quality, as nutrients added from urine and fecal material over the winter can end up in runoff water, ground water and soil. In 2008/2009 an experiment was conducted to observe the effect of in-field winter feeding of cows on the nutrients in spring snowmelt run-off water. Low temperatures give little opportunity for o...

Forest harvesting disrupts the nitrogen cycle, which may affect stream water quality by increasing nitrate concentrations, reducing pH and acid neutralizing capacity, and mobilizing aluminum and base cations. We tested the application of wood chips derived from logging slash to increase immobilization of N after harvesting, which should reduce nitrate flux to streams. In August 2004, a stand of...

Wetland loss along the Louisiana Gulf coast and excessive nitrate loading into the Gulf of Mexico are interrelated environmental problems. Nitrate removal by soil denitrification activity was studied in a ponded freshwater marsh receiving diverted Mississippi River water for the purpose of reversing or slowing wetland loss. Labeled (15)N-nitrate was applied at 3.8 g N m(-2) into four replicate ...

knowledge of crop N need may be used by producers to guide future fertilizer-N management thereby improving The end-of-season stalk nitrate test provides a method of assessing profitability and reducing environmental degradation. the N available to the corn (Zea mays L.) crop during the latter part of the season. This study was conducted to determine how stalk nitrate To be a useful crop manage...

The leachate contains dissolved and suspended organic and inorganic, toxic or chemicals pollutants. Leachate can contaminate groundwater, surface water and soil. It can further have detrimental health effects on human being. This study sets out to investigate the effects of land treatment of municipal landfill’s leachate on the natural reduction of nitrogen and phosphorous density existing in t...

The characteristics of nitrate uptake and induction of nitrate reductase were studied in excised roots of corn (Zea mays L.). Upon initial exposure to nitrate, the low initial rate of nitrate uptake gradually increased until a steady uptake rate was achieved in 1 to 2 hours depending on the NO(3) (-) concentration. The pattern was observed over a wide range (0.2-5 mm) of nitrate concentrations ...

On a Flemish sandy loam soil, cut and grazed swards were compared at different levels of mineral nitrogen (N) fertilization. Economically optimal N fertilization rates were 400 (or more) and 200 kg N ha yr on cut and grazed swards respectively. Considering the amounts of residual soil nitrate-N in autumn, these N rates also met the current Flemish legal provisions, i.e. no more than 90 kg ha ni...