Non-point source (NPS) pollution has been increasingly serious in China since the 1990s. The increases of agricultural NPS pollution in China is evaluated for the period 2000-2008 by surveying the literature on water and soil pollution from fertilizers and pesticides, and assessing the surplus nitrogen balance within provinces. The main causes for NPS pollution were excessive inputs of nitrogen...

proper application of n fertilizer and its optimization for increasing the economic yield of rice is definitely important. in order to determine the best n application method and amount according to growth stages of hybrid rice, an experiment was carried out at experimental farm of rrii in a factorial experiment based on a randomized complete block design with 3 replications. the treatments inc...

A field micro-plot experiment using nitrogen isotope (15N) labeling was conducted to determine the effects of placement methods (broadcast and band) and N rates (60, 150 and 240 kg ha-1) on the fate of urea-15N in the wheat-soil system in Guangde County of Anhui Province, China. N fertilizer applied in bands increased grain yield by 15% compared with broadcast application. The N fertilizer appl...

The use of efficient rates of nitrogen (N) fertilizer application is important with regard to increasing crop productivity and maintaining environmental sustainability. Rice-oilseed rape rotations are a mainstay of the economy and food security of China. Therefore, a field experiment was carried out during 2011-2013 in Honghu to identify the most appropriate N application rates for enhancing cr...

Recent natural gas price increases have resulted in acutely higher fertilizer prices. Profit and environmental concerns have increased interest in identifying optimal nitrogen application rates. Previous estimates of the profit maximizing nitrogen rate (PMNR) have been estimated assuming that price is fixed and exogenous of yield. We construct a model in which price is correlated to yield shock...