Nitrogen for plant nutrition is mainly obtained from three sources: nitrogen-fixing plant, rain water and manure.
氮素是植物必要的营养元素之一，其主要来源有：生物固氮作用、降雨和灌溉水以及人工施肥。
2
The effect of cellulose-decomposing fungus(CDF) mixed with associative nitrogen-fixing bacterium(ANFB) to cellulose-decomposing has been studied.
从纤维素分解菌与联合固氮菌的接种配比，研究了混合培养对滤纸分解的影响。
3
Actinorhizal Plants are a kind of important natural nitrogen-fixing resources, and they have high value in reforestation as pioneer and accompanying species.