Background: Qual2k is a stream water quality model and was used to evaluate the water quality of the Kine-Vars River and assess the response of the river to nutrient management strategies. Methods: For that purpose, 7 sample stations were selected and surface water samples were collected in the winter and summer of 2012 and were analyzed for temperature, dissolved oxygen, biological oxygen dem...

Nitrogen (N) is the primary growth-limiting nutrient in many terrestrial ecosystems, and therefore plant production per unit N taken up (i.e., N use efficiency, NUE) is a fundamentally important component of ecosystem function. Nitrogen use efficiency comprises two components: N productivity (A(N), plant production per peak biomass N content) and the mean residence time of N in plant biomass (M...

abstract water and nitrogen are the main limiting factors affecting agricultural production in arid and semiarid regions. therefore, improving the efficiency of these factors is very important. the method of fertilizer application is affecting water and fertilizer use efficiency. the objective of this study was to investigate the effect of furrow fertigation on fertilizer use efficiency (fue), ...

Extraordinary importance of Date-Palm, Phoenix dactylifera especially ‘Piarom’ variety and also undeniable effect of nitrogen and phosphorus on yield and quality of this product, caused this research to be accomplished. The research was performed during two years on 72 (4*3*3*2=72 trees) fruitful, 12 years old trees in Hormozgan province. Treatments were consisted of four levels of nitrogen (0,...

plackett-burman design was used for selection of important media components such as carbon and nitrogen sources and minerals which affect poly(hydroxybutyrate) production and cell growth of methylobacterium extorquens dsmz 1340. among the studied variables, nitrogen and phosphorus sources, mgso4 and most of the trace elements were found to be significant variables for phb production from methan...

in order to study the effects of drought stress and nitrogen (n) levels on grain yield, yield components and water use efficiency of grain corn (sc.704), a field experiment was conducted in 2009 growing season. the experiment was split-plot based on randomized complete block design arrangement and four replicates. main plots were three irrigation levels included optimum irrigation (i1), moderat...