砷污染湖滨湿地底泥微生物群落结构及多样性

为研究高原砷污染湖滨湿地底泥微生物群落结构及多样性特征，探寻底泥砷含量及砷形态与微生物之间的联系，采集云南省阳宗海东、西、南、北岸湖滨湿地底泥样品，利用16S rRNA高通量测序技术，研究了砷污染湖滨湿地底泥微生物丰富度特征，探讨了不同砷形态差异对微生物群落的影响.结果显示，底泥砷含量对微生物丰富度影响显著，砷含量高的南岸区域微生物的丰富度较高，OTU为1286~1473.而砷含量较低的西岸区域微生物丰富度也随之较低，OTU为693~1339.阳宗海湖滨湿地底泥微生物群落结构稳定，主要优势类群为Proteobacteria（变形菌门，15.6%~59.6%）、Chloroflexi（绿弯菌门，10.1%~44.9%）及少量的Actinobacteria（放线菌门）和Acidobacteria（酸杆菌门）.底泥中砷形态主要以残渣态砷（F5）和无定型氧化物结合态砷（F3）为主，无定型氧化物结合态砷（F3）对底泥微生物类群影响最为显著.同时，底泥中生物有效态砷（非专性吸附态砷+专性吸附态砷+无定型氧化物结合态砷）占到19.3%~58.6%，存在环境释放风险.研究结果加深了对砷污染高原湖泊底泥中微生物群落的认识，为湖泊砷污染防治提供微生物治理的理论基础和科学依据.

Microbial community structure and diversity of arsenic-contaminated lakeshore wetland sediments

The purpose of the present work was to explore the microbial community structure and diversity characteristics of arsenic-contaminated lakeshore wetland in the Plateau lakes, and to explore the relationship between the content & forms of arsenic and microbial community characteristics in the sediment. This paper collected samples of lakeshore wetland sediments from the east, west, south and north lakeshore of Yangzonghai Lake in Yunnan Province, not only the characteristics of microbial richness in sediments of arsenic-contaminated lakeshore wetlands were analyzed by 16S rRNA high-throughput sequencing technique, but also the effects of arsenic forms on microbial communities were discussed. The results showed:(1) the arsenic content of the sediment has a significant effect on the microbial richness, and the microbial richness is higher with high arsenic content in the South Bank region, which the Operational Taxonomic Units is 1286~1473, In the West Bank region the microbial richness is low with low arsenic content which the Operational Taxonomic Units is 693~1339; (2) The microbial community structure of sediments in Yangzonghai Lake Lakeshore wetland is stable, the dominant populations are Proteobacteria (15.6%~59.6%), Chloroflexi (10.1%~44.9%), with few Actinobacteria and Acidobacteria; (3) The arsenic form in the sediment is mainly composed of residual arsenic (F5) and amorphous oxide-bound arsenic (F3), and F3 has the most significant effect on the microbial community. Meanwhile, the bioavailable arsenic (non-specific adsorbed arsenic + specific adsorbed arsenic + amorphous oxide bound arsenic) in the sediment accounts for 19.3%~58.6%, the risk of arsenic release is high. The research results deepened the understanding of microbial community in sediments of arsenic-contaminated plateau lakes, and provide theoretical and scientific basis for microbial treatment of lake arsenic pollution prevention.