阐述了不同水平有机肥及无机N肥长期定位施用对露地土壤 -蔬菜生态系统变化的影响 ,明确指出长期偏施N肥明显地破坏该系统的结构 ,降低系统的功能 ,配施有机肥可在一定程度上得到改善 ,但在土壤肥力提高到一定水平后应增施P、K肥 ,防止土壤养分平衡的失调。 The effects of different levels of organic manure and inorganic N fertilizers on the changes of soil-vegetable ecosystem in open field were described. It was clearly pointed out that the long-term partial application of N fertilizer obviously damaged the structure of the system and reduced the function of the system. To some extent improved, but after soil fertility increased to a certain level should be increased P, K fertilizer, to prevent imbalance of soil nutrient balance.