我国不同区域小麦施肥资源环境影响的生命周期评价

以河南、江苏和陕西三省的小麦生产体系为例,以生产1 t小麦为评价的功能单元,应用生命周期评价（LCA）方法,比较了不同生态区小麦施肥的资源环境影响潜力。结果表明,三省环境影响综合指数大小依次为江苏0.288、河南0.201、陕西0.180。几种资源环境影响中,潜力大小依次是富营养化、环境酸化、温室效应、土地利用和能源消耗,其中施用氮肥引起的氨挥发是导致富营养化和酸化的主要因素。农户间生产的资源环境影响潜力差异很大,环境影响综合指数变异范围在34.9%～57.3%,陕西最高,江苏最低。如果将小麦追肥由撒施都改为沟施,三省的环境影响综合指数将降低28.0%～45.4%。

Life Cycle Assessment of Wheat Fertilization in Different Regions of China

Wheat is a key crop in China,consequently it is very important to assess the integrated environmental impacts of wheat production because it is associated with excessive fertilization.In this study,examples of Henan,Jiangsu and Shaanxi identified within different eco-districts were taken to evaluate the individual and integrated environmental indices using life cycle assessmen（tLCA）method.For simplicity,the individual and integrated environmental indices were estimated on the base of emissions,resource and energy consumptions to produce 1 ton wheat.Results showed that the integrated indices of these provinces were in an order of 0.288（Jiangsu）,0.201（Henan）and 0.180（Shaanxi）.Of the individual indices,they were in an order of eutrophication,acidification,global warming,land use and energy consumption,where eutrophication and acidification were mainly caused by ammonia volatilization during N fertilization.Large variation of environmental indices between farms of each province was recognized and the coefficient variances ranged from 34.9%~57.3%,in particular,Shaanxi and Jiangsu were with the highest and lowest environmental index respectively.Given the top-dressing of N fertilization were replaced with deep application,the integrated environmental indices would be reduced by 28.0%~45.4%.