论文部分内容阅读
森林生态系统中,氮累积的速度及数量对各生物组分的发生、繁育、演替以及生物生产量都起着重要作用。生物固氮是大气中氮素向森林生态系统输入的一个重要途径,包括土壤中自生固氮菌的固氮以及某些森林植物与特定的根瘤菌、放线菌等微生物的共生固氮作用。据统计,生物固氮的数量占整个生态系统输入量的6/7。长白山的森林是北温带地域内植被较为复杂,垂直分布带非常明显的针、阔叶天然林。从海拔500米的针阔混交林带到2,000米的亚高山岳桦带,经初步调查,高等植物中就有12个种具有结瘤固氮能力。其中分布较广、结瘤较多的是东北赤杨[Alnus mandshurica(Call.)
In forest ecosystems, the rate and amount of nitrogen accumulation play an important role in the occurrence, breeding, succession and biomass production of various biological components. Biological nitrogen fixation is an important way for the input of nitrogen to the forest ecosystem in the atmosphere, including the nitrogen fixation of autotrophic Azotobacter in soil and the symbiotic nitrogen fixation of certain forest plants with certain rhizobia and actinomycetes. According to statistics, the number of biological nitrogen fixation of the entire ecosystem input 6/7. The forest of Changbai Mountain is a needle and broad-leaved natural forest with more complicated vegetation in the north temperate zone and very obvious vertical distribution. From a coniferous and broad-leaved forest with an elevation of 500 meters to a 2,000-meter sub-alpine mountain birch, preliminary investigation revealed that 12 species of higher plants have nodulation and nitrogen fixation ability. Among them, the distribution is wider and the nodulation is more in Alnus mandshurica (Call.)