滇池湿地满江红根际微生物群落组成与水质关联研究

Association Between Composition of Rhizosphere Microbial Community and Water Quality of Azolla imbricate in Tien Lake Wetland

利用漂浮植物修复富营养化水体是目前湿地公园在设计和构建中重要的措施,但湿地水质净化效果和漂浮植物根际微生物群落组成之间的关联及响应机制研究较少。为了探寻一种能够科学监测、管理和控制滇湿地水体质量的有效方法,该文采用荧光原位杂交(fluorescence in situ hybridization,FISH)技术对3个环滇池湿地春、秋两季满江红根际微生物群落的组成和分布进行了研究,对3个湿地水体的理化指标和满江红的生长指标进行了测量,并进一步分析了根际微生物群落、满江红生长指标和湿地水体理化性质三者之间的响应机制。结果表明满江红根际微生物群落组成复杂,主要的微生物群落由变形菌门、广古菌门和放线菌门组成,其中3个湿地满江红根际微生物群落的优势菌群变形菌门丰度在41.73%~54.79%之间。3个湿地水体理化性质测定结果显示秋季水体理化性质的各项指标普遍都高于春季,Spearman相关性分析结果指出满江红的根长、叶长和叶宽与湿地水体的总磷、总氮、氨氮和COD、满江红的干重与总磷和总氮存在显著(p<0.05)正相关。研究表明湿地水体中的氮、磷和COD的含量变化与满江红根际微生物群落的组成有关联,对满江红根际微生物群落的组成和丰度进行追踪是监测、管理和控制湿地水体质量的一种潜在有效手段。

It is a very important project during designing and construction of wetland parks by applying floating plants to purify wetland water due to eutrophication,but there are few studies on the correlation and response mechanism between the effect of water purification and rhizosphere microbial communities of floating plants.In order to detect an available method that can be scientifically used to monitor,manage and control the water quality of the Tien Lake wetlands,fluorescence in situ hybridization(FISH)technique was used to explore the composition and distribution of the rhizosphere microbial communities of Azolla imbricate in three different wetlands during spring and autumn,physicochemical characteristics of wetland water and growth factors of Azolla imbricate of the three wetlands were analyzed.Finally the response mechanism was analyzed among rhizosphere microbial communities,growth factors of Azolla imbricate and physicochemical characteristics of wetland water.The results showed that the compositions of the rhizosphere microbial community of Azolla imbricate were very diverse.The dominate parts were consisted by Proteobacteria,Euryarchaeota and Actinobacteria,over them the Proteobacteria was the most dominate group ranged from 41.73%to 54.79%.The data of physicochemical characteristics of wetland water in autumn were bigger than those in spring.All results showed that the root length,leaf length and leaf width of Azolla imbricate were positively correlated with total phosphorus,total nitrogen,ammonia nitrogen and COD(p<0.05).The study indicated that the degradation of nitrogen,phosphorus and COD of wetland water was closely related to the compositions of the rhizosphere of Azolla imbricate.It was found that it is a potential method to monitor,administer and control the qualities of wetland water by detecting the compositions and abundances of the rhizosphere microbial communities of Azolla imbricate.