武昌湖典型退化湿地菰草根际微生物群落结构

Microbial Diversity of ZizaniaLatifolia Rhizosphere in Typical Degenerating Wetland of Wuchang Lake

为研究淡水湖泊湿地微生物群落结构与退化湿地环境之间的关系,选取武昌湖湿地菰草根际水体、根际土壤、根下湖泊沉积物3组环境样本,提取样本微生物基因组DNA,并利用16S r DNA基因进行454高通量测序,共得到优质序列17 051条,产生2 062条OUTs。结果表明：武昌湖退化湿地菰草根际具有较为复杂的微生物群落结构,涉及15门48属,其中以变形菌门（Proteobacteria）、拟杆菌门（Bacteroidetes）、酸杆菌门（Acidobacteria）和绿弯菌门（Chloroflexi）为主要门类;菰草根际不同微环境微生物群落结构存在明显差异,生物多样性指数Shannon、Chao、ACE指数及OTUs均呈现根际土壤〉湖泊沉积物〉根际水体的变化特征。探究湿地退化过程中植被菰草根际微生物群落结构特征,对揭示长江中下游浅水湖泊湿地退化机理具有重要意义。

To better understand the relationships between microbial communities in freshwater wetland and wetland degradation, soil, water and sediment samples in rhizosphere of invaded Zizanialatifolia were selected from Wuchang Lake wetland. Total DNA Extraction tested samples were conducted to analyze bacterial community structures by high-throughput sequencing based on 16S rDNA gene. Finally, 17 051 high quality sequences were obtained; whilst OTUs number was 2 062. Results show that the rhizosphere soil of Zizanialatifolia has complex microbial community structure, including 15 phyla and 48 genera. Additionally, the main phyla contained Proteobacteria, Bacteroidetes, Acidobacteria and Chloroflexi in the three sample types in rhizosphere. Diversity indexes of Shannon, Chao, ACE and OTUs reveal the similar variation trend of SI〉Sla〉W1, indicating that microbial communities are obviously different from soil, water and sediment in rhizosphere. Studying microbial diversities in rhizosphere of Zizanialatifolia in the degenerating wetland should play an important role in understanding the natural wetland degeneration in the middle and lower reaches of the Yangtze River.