Spatial Distribution of Sediment Bacterial Communities in Eutrophicated Meiliang Bay: Correlation with Environmental Factors

Abstract

Bacterial community structure and the effects of several environmental factors on the spatial distribution of bacterial communities were investigated in the sediment of Meiliang Bay in a large, shallow, eutrophic freshwater lake. Water and surface sediment samples were collected at 10 sampling sites on 15 September 2013. Based on cluster analysis of the DGGE banding patterns, there were no significant variations in spatial distribution of bacterial community structure of the 10 sediment samples in the eutrophicated Meiliang Bay. The dendrogram of the bacterial community similarities in the 10 samples revealed that samples grouped into two defined clusters with a 60% similarity. Analysis of DNA sequences showed that the dominant bacterial groups in the Meiliang Bay belonged to Proteobacteria, Acidobacteria, Cyanobacterium, Planctomycetes, and Verrucomicrobia, which commonly exist in freshwater ecosystems. In addition, some Actinobacteria, Firmicutes, Nitrospirae bacterial groups were also found in the Meiliang Bay. The transformation of nitrogen and phosphorus nutrients in the water and sediments of Meiliang bay influenced on bacterial community in the sediments. Canonical correspondence analysis demonstrated that total nitrogen and total phosphorus in the sediment significantly influenced the bacterial community structure in the sediment of Meiliang Bay.