几种湿地植物的氮素累积量与其根际固氮菌总数之间相关性分析

A Study on Relationship between Nitrogen Accumulation of Several Wetland Plant Species and Biomass of Their Rhizospheric Nitrogen-fixing Bacteria

为研究湿地植物的氮、磷累积量与其根际微生物之间的相关性，并调查湿地植物的净化潜能，结合位于洱海北部的弥苴河河口湿地恢复和示范技术，对芦苇、茭草、纸莎草．水葱、美人蕉和鸢尾6种湿地植物进行了相关性研究分析。结果表明，芦苇，美人蕉氮素累积量与其根际固氮菌总数呈显著正相关关系，而其他4种湿地植物的相关性不显著。针对湿地系统的环境因素，如表层土壤全氮、湿地水体总氮和溶解氧的影响，也作了简单的回归分析和偏相关分析。数据显示，三者对根际固氮菌数量均有较大的影响；而芦苇、美人蕉氮素累积作用与其根际固氮菌的相关性受3种环境因素的影响甚微，进一步证实芦苇、美人蕉的氮素累积量与其根际固氮菌之间存在着协同代谢活动。

In order to investigate the correlation of nitrogen and phosphorus accumulation with rhizospheric microbes, as well as the assimilative potentials of several wetland plant species, such relationships of Phragmites communis, Zizania caduciflora Hand Mazz, Cyperus papyrus Linn, Scirpus validus Vahl, Canna indica and Iris germanica Linn were studied in combination with the research on wetland restoration and its demonstration technologies for Miju River estuary situated at the northern Erhai Lake. The correlation between nitrogen accumulation of Phragmites communis and Canna indica and biomass of their rhizospheric nitrogen-fixing bacteria was found evidently positive, whilst that of the others was unmarked. Furthermore, simple regression and partial correlation analyses were also conducted to focus on the influence of environmental factors of the wetland system such as total nitrogen in surface soil, total nitrogen and dissolved oxygen in water body. In general, all of the factors would make rather great impacts on the biomass of rhizospheric nitrogen-fixing bacteria. However, the correlation of nitrogen accumulation of Phragmites communis and Canna with their rhizospheric nitrogen-fixing bacteria was slightly affected by those environmental factors, and it was further confirmed that there were co-metabolic activities between their nitrogen accumulation and rhizospheric nitrogen-fixing bacteria.