资源环境科技发展态势分析平台

Overuse of nitrogen (N) fertilizer, a crucial productivity factor in world cropping systems, is detrimental to the sustainability of crop production from an economic and environmental perspective. Mean yield, N fertilizer use, partial factor productivity (PFP) of N, N use efficiency (NUE) and N surplus in wheat, cotton and rice production in Pakistan, which account for 75% of total national fertilizer N use, were compared with those for the top producer countries for 2014. Pakistan was among the top four in terms of N use but had low mean yields, with the lowest PFP and NUE and highest N surplus. During 1961-2014 in Pakistan, N fertilizer use and N surplus grew at a much faster pace than mean yields; however, PFP and NUE continued to decline to much lower levels. The great potential for Pakistan to increase NUE lies in agronomic practices other than increasing N fertilization, such as balanced crop nutrition, irrigation management, inclusion of legumes in crop rotations, precision in-season N management and the use of enhanced efficiency fertilizers, as is the case for many other parts of the world.