methylene blue is widely used in various industrial branches. due to insufficient treatment, its occurrence in wastewater is frequently detected, which may result in serious environment problems to aquatic organisms. hydroponic experiments were conducted with rice seedlings (oryza sativa l. cv. xzx 45) exposed to methylene blue to determine the effective concentration using relative growth rate...

increasing resource use efficiency is one of the important ways to enhance agricultural productions and reduce environmental hazards. for this purpose, improvement of n use efficiency is an effective approach. nitrogen losses not only occur in field but also in the processing course. the objective of this study was to calculate nitrogen losses and efficiency during production to consumption for...

in order to evaluate radiation capture and use efficiency and productivity in sole and intercropping of three crops, rapeseed (brassica napus l.), bean (phaseolus vulgaris l.) and corn (zea mays l.), an experiment was conducted in mashhad region during the growing season of 2007-2008. in this study six treatments including three sole cropping of the crops (rapeseed sown in 22 september 2007, co...

In recent decades, the land use changes induced by various economic activities in agricultural ecosystems have affected many aspects of human life. This is reason why change considered as one agriculture-related environmental impacts a sustainability assessment food and bio-based products. At same time, methodology applied for quantification effects still under intensive research, stimulating s...

water is one of the most important and limited inputs in agricultural productions. the aim of water resources management in agriculture is increasing production performance and raising water use efficiency. to achieve this, in the present research, the water use efficiency of the main agricultural products and farmers of zabol district was studied using data envelopment analysis (dea) in 2011. ...

Common belief and some empirical evidence indicates that productivity of a farmer may increase with age, reach some maximum level, and then decrease with further age (Tauer 1984; Tauer 1995). If productivity exhibits a life-cycle pattern, then productivity of agriculture may decrease as the U.S. farm population continues to age. Lifecycle changes are also critical in planning for succession of ...

found, had they considered N derived from the soil (Keeney, 1982; van der Ploeg et al., 1997). Using the Worldwide, nitrogen use efficiency (NUE) for cereal production same references and assumptions in Table 1, cereal (wheat, Triticum aestivum L.; corn, Zea mays L.; rice, Oryza sativa L. and O. glaberrima Steud.; barley, Hordeum vulgare L.; sorghum, NUEs are 42 and 29% in developed and develop...