Flooded paddy soil ecosystems in the tropics support the cultivation of the majority of the world's leading crop, rice, and nitrogen (N) availability in the paddy-soil rooting zone limits rice production more than any other nutritional factor. Yet, little is known about the dynamic response of paddy soil to N-fertiliser application, in terms of horizontal and vertical patchiness in N distributi...

high quantity of chemical fertilizer use in farms to increase production but low efficiency irrigation leaches part of nitrate and follows groundwater pollution. in this research, extra water below root zone as deep percolation collected with point drains which installed interface of natural drainage zone and agricultural soil in university of tehran research farms. then, concentration of nitra...

The end-of-season corn (Zea mays L.) stalk nitrate-N test was developed as a post-mortem to determine if excessive or insufficient N was available to the corn crop during the latter part of the season. The stalk section specified for the test was very specific, the 20 cm-long section between 15 and 35 cm above the soil. Under production conditions, it may not always be possible to collect this ...

Background and Purpose: Elevated nitrate concentrations in drinking water can cause methemoglobinemia in infants, stomach cancer in adults and nitrate poisoning in animals as well. Modeling of nitrate fate and transport in groundwater to minimize nitrate concentration in groundwater has been studied by numerous researchers. Materials and Methods: In order to determine the pote...

the use of fertilizers in agriculture is a potential source of environmental pollution especially in ‎water quality and soil resources. the study of effective factors on water and nutrient transport ‎through soil profile is helpful for nutrient management to minimize adverse impacts on environment ‎and nitrate leaching below root zone. in this study, for assessing the nitrate transportation bel...

The photochemical persistence of quinalphos, one of the most widely used organophosphorous insecticides, was investigated in a variety of environmental matrices such as natural waters and soils of different composition. Simulated solar irradiation was obtained using a xenon arc lamp (Suntest CPS+ apparatus) giving an irradiation intensity of 750 W m(-2) equivalent to a light dose per hour of ir...

Understanding the responses of terrestrial ecosystems to global change remains a major challenge of ecological research. We exploited a natural elevation gradient in a northern hardwood forest to determine how reductions in snow accumulation, expected with climate change, directly affect dynamics of soil winter frost, and indirectly soil microbial biomass and activity during the growing season....

nitrate pollutants increase the growth of algal bloom, resulting in fresh water eutrophication. the high nitrogen level in wastewater has become a growing concern, which has risen the necessity to develop efficient nitrogen removal techniques. biological denitrification, which is the reduction of oxidized nitrogen compounds like nitrate or nitrite to gaseous nitrogen compounds, is the most impo...