非共生固氮是水稻土氮素循环中的一个基本环节。作为一个基础数据,人们首先需要知道稻田土壤中的非共生固氮量。在这一方面已经有了一些总结性报导,其中主要是通过长期试验中氮素平衡账的估算而获得的。但国内迄今还未见这类报告。从另一方面来看,稻 Non-symbiotic nitrogen fixation is a basic part of nitrogen cycling in paddy soil. As a basic data, people first need to know the amount of non-symbiotic nitrogen fixation in paddy soil. There have been some summary reports in this regard, mainly through the estimation of the nitrogen balance in long-term trials. However, so far no such reports have been reported in China. On the other hand, rice