中国三大粮食作物化肥施用特征及环境风险评价

基于中国三大粮食作物化肥施用强度及配方肥用量核算数据,运用化肥施用环境风险评价模型定量分析了2016年中国三大粮食作物化肥施用特征及其环境风险。结果表明:(1)2016年中国三大粮食作物普遍存在化肥施用过量现象,且不同区域之间单质肥料施用过量程度差异显著,其中,小麦和玉米种植单质肥料存在施用过量的空间范围及过量程度整体上要高于水稻。(2)中国三大粮食作物化肥施用环境风险具有显著的空间差异性,且处于相同风险等级的区域呈现出一定的空间邻近性。(3)中国三大粮食作物总化肥环境风险水平整体较低,但内蒙古、新疆和江苏的小麦种植以及内蒙古、甘肃和湖北等地的玉米种植化肥施用环境风险仍达到了中度或重度风险等级,应成为重点关注的区域。针对当前三大粮食作物化肥施用过量现象严重的问题,政府应当加快三大粮食作物配方肥的推广应用,出台政策措施鼓励企业按大配方生产配方肥,并引导企业在适宜地区进行销售,制定补贴政策以提高农民选用配方肥的积极性,开展科学指导和技术服务以提高农户科学施肥能力和认知水平。

Characteristics of Chemical Fertilizer Application and Environmental RiskAssessment of Three Major Food Crops in China

Based on the data of chemical fertilizer application intensity and recommended amount of formula fertilizer, the paper used environmental risk assessment model to evaluate the environmental risk of chemical fertilizer application of three major food crops in 2016 in China. The results showed that: (1) The phenomenon of chemical fertilizer over-application existed generally in three major food crops in China, and there was a significant difference in the degree of excessive application of nitrogen, phosphorus and potash between different regions. The spatial scope and degree of excessive application of chemical fertilizer of wheat and maize were higher than that of rice on the whole. (2) The environmental risk of chemical fertilizer application among three major food crops demonstrated significant different patterns of spatial distribution in China, and the regions which were at the same risk level showed certain spatial proximity. (3) The environmental risk of chemical fertilizer application for three major food crops in China was generally low, but the environmental risk of wheat planting in Inner Mongolia, Xinjiang and Jiangsu and maize planting in Inner Mongolia, Gansu and Hubei had reached a moderate or severe risk level, which should be the focus of attention. Targeting at the current problems of chemical fertilizer over-application in China, the government should speed up the popularization and application of formula fertilizer for three major food crops, introduce policies and measures to encourage enterprises to produce formula fertilizer according to large formula, guide enterprises to sell the formula fertilizer in suitable areas, formulate subsidies policies to improve farmers' enthusiasm for selecting formula fertilizer, and carry out scientific guidance and technical services to improve farmers' scientific fertilization ability and cognitive level.