关键词: 化肥减量, 粮食产量, 分位数回归, 边际效用, 主粮作物

Abstract:  The impact of chemical fertilizer on grain production is an important issue in the study of the grain economy. Based on the panel data of the amount of chemical fertilizer and the grain yield of corn, wheat, and rice in Chinas major grainproducing areas from 1994 to 2018, this paper designed a quantile regression model to analyze the impact of chemical fertilizer application on the grain yield. The Research showed that with the continuous increase in the amount of chemical fertilizer, the grain yield per unit area had a significant correlation effect with it, and had the obvious characteristics of periodic growth. Before 1997, the fluctuation degree of amount of chemical fertilizer used and the grain yield per unit area tended to the same level. From 1998 to 2004, the amount of chemical fertilizer used showed a large jump in the trend, but the total yield remained above 5 000 kg/hm2. From 2004 to 2015, the amount of chemical fertilizer used and grain production showed a gradually increasing development trend. After 2016, the amount of chemical fertilizer used and the grain yield showed a small increase and then a small decline. In addition, at the 0.1-0.9 quantile, with the increase of the quantile, the fertilizer application rate had a positive effect on the yield per unit area of maize, but the marginal utility was decreasing. On the other hand, the effect of fertilizer application on yield of wheat and rice gradually weakened. On the premise of insisting on zero growth of chemical fertilizer application, we should pay attention to scientific fertilization and combined application of organic fertilizer to improve the utilization rate of chemical fertilizer, so as to achieve a balance between ensuring food security and promoting sustainable development of agriculture.

Key words: chemical fertilizer reduction, grain yield, quantile regression, marginal utility, staple crops