水生经济植物根际氮循环细菌及其作用的研究

Research on the Nitrogen Cycle Bacteria and Actions in the Rhizosphere of Economic Aquatic Plants

利用生态浮床系统,在室内研究了浮床植物单作和混作对氮的去除效果及其根际周围硝化与反硝化菌种群数量以及硝化与反硝化作用速率的变化规律。结果表明,浮床植物混作系统对氮的去除效果优于植物单作和无植物系统,而植物系统又优于无植物系统;植物单作与混作根际硝化细菌种群数量和硝化作用速率、反硝化细菌种群数量和反硝化作用速率均具有明显的差异;处理15 d后,硝化细菌种群数量在水芹系统中的减少较比豆瓣菜和混作系统多,硝化作用速率在水芹系统中的降低较豆瓣菜和混作系统明显(P<0.05);反硝化细菌种群数量由多到少的顺序分别为水芹系统,豆瓣菜系统,混作系统,无植物系统;且反硝化作用速率由高到低的顺序分别为水芹系统,豆瓣菜系统,混作系统,无植物系统。

Nitrogen removal in eutrophic water was studied by monoeulture and mixture plants in ecological floating bed system in the greenhouse. At the same time, the numbers of nitrifying and denitrifying bacteria population and the nitrification and denitrification rate in the floating bed plant rhizospere were quantified. The results showed that nitrogen removal in mixture system was outperformed the monoculture＇and no plant system, and the plant system was outperformed no plant system. There was significant difference between the monoculture and mixture system by the numbers of nitrifying bacteria population and denitrifying bacteria population and denitrification rate. In contrast to watercress system and mixture system, the numbers of nitrifying bacteria population and nitrification rate decreased obviously （P 〈0.05） in the water dropwort system, the order of the numbers of denitrifying bacteria population and denitrification rate after 15d treatment is： water dropwort system〉 watercress system 〉mixture system 〉no plant system.