Nitrogen utilization by corn (Zea mays L.) is influenced by the form of inorganic N present in the root zone. A field experiment was conducted on Enon sandy loam (fine, mixed, thermic Ultic Hapludalf) to determine N use efficiency and its partitioning in various plant parts of corn. Ammonium nitrate labeled either as NH4-N or NO3-N and applied at 50, 100, or 200 kg N ha" was evaluated. Microplo...

Protection of ground water for present and future use requires monitoring and understanding of the mechanisms controlling long-term quality of ground water. In this study, spatial and temporal trends in concentrations of nitrate and pesticides in ground water in the eastern San Joaquin Valley, California, were evaluated to determine the long-term effects of agricultural and urban development on...

We studied nutrient balance in a paddy field that had a recycling irrigation system and evaluated the effect of the irrigation system on nutrient balance during the irrigation period, from April to August 2002. Chemical fertilizer was the main input of phosphorus; the soil absorbed about 56% of it. The amount of nitrogen supplied by the irrigation system was higher than in a representative padd...

Conventional and alternative sanitation concepts are compared in terms of their ecological performance via the methodology of LCA. Alternative scenarios include urine separation, faeces composting and digestion, and greywater treatment in a soil filter or technical plant. Urine and faeces are used as secondary fertilizers in agriculture after adequate treatment. Data for Life Cycle Inventory is...

We investigated the variation in leaf nitrogen to phosphorus ratios of tropical tree and liana seedlings as a function of the relative growth rate, whole-plant water-use efficiency, soil water content and fertilizer addition. First, seedlings of 13 tree and liana species were grown individually in 38-l pots prepared with a homogeneous soil mixture. Second, seedlings of three tree species were g...

nowadays, with population growth in urban areas, providing safe water and health is considered basic needs of human, alongside the various pollutants due to urban activities, agriculture and industrial areas on adjacent ranges into urban water resources around the environment is such that study necessary to prevent the pollution of water resources and identification of pollution sources shows. ...

Experiment was conducted as split plot in a randomized complete block design with three replications in Kermanshah to shed lights on economic analysis of deficit irrigation and integrated application of biological and chemical fertilizer son cultivation of medicinal plant Borage (Borago officinalis L). Irrigation tritments include: a) 30% less water than crop requires invegetative, b) inreprodu...

water and nitrogen fertilizer are two main factors of agricultural production and deficiency of each one makes reduction in the yield. deficit irrigation is one of the ways for water management in arid and semiarid areas, but it is effective on the need of nitrogen. excessive use of nitrogen will be a waste of capital and environmental pollution. in this study the interaction of water and nitro...