我国已进入WTO,蔬菜生产必须要与国际接轨,即生产出的蔬菜要达到国家规定的绿色食品标准:无巨毒高残留农药的污染、重金属含量不超标、硝酸盐含量不超标(国际上规定每公斤鲜菜硝酸盐含量低于432毫克)、无病虫卵。如何通过施肥减少蔬菜中硝酸盐的积累,是无公害蔬菜施肥应注意的问题: 1.重视施用有机肥料。有机肥有鸡、猪及牲口粪和矿物有机肥,如草炭、泥炭与褐煤等腐殖质类肥料。农村有机肥必须先经过高温发酵,粪堆内温度达到60℃～70℃持续6～7天,再经倒翻,将外层的粪料倒入内层继续发酵,在温度达 China has entered the WTO, vegetable production must be in line with international standards, that is, to produce vegetables to meet the state green food standards: non-toxic high residual pesticide pollution, heavy metal content does not exceed the standard, nitrate content is not exceeded (international regulations Nitrate content per kilogram of vegetables less than 432 mg), no pest eggs. How to reduce the accumulation of nitrate in vegetables by fertilizing is the problem of pollution-free vegetable fertilization should pay attention to: 1. Emphasis on the application of organic fertilizer. Organic fertilizer with chickens, pigs and livestock dung and mineral organic fertilizer, such as peat, peat and lignite and other humus fertilizer. Rural organic fertilizer must be subjected to high temperature fermentation, dung pile temperature reached 60 ℃ ~ 70 ℃ for 6 to 7 days, and then inverted, the outer layer of feces poured into the inner layer to continue fermentation at temperatures up to