Research On Metagenomic Of Microbes And Diversity Of Nitrogen Transformation Strains In The Sediment From Different Areas Of Lake Taihu

This study was conducted to characterize the distribution of nutrient elements、composition of the microbial community and diversity of Anaerobic ammonia oxidationbacteria in the sediment samples collected from Lake Taihu, a typical eutrophic lake，using polymerase chain reaction （PCR）、 clone library、 denaturing gradient gelelectrophoresis (DGGE) and sequencing technique．An investigation, conducted on the distribution of nutrient elements in the water andsediment from Zhushan lake and Meiliang lake, suggested that the water from Zhushanlake was more eutrophic than that from Meiliang lake, however, the eutrophic levelof the sediment from the two lakes had no significant difference. The TP concentrationof water and sediment was significantly correlated, but the concentration of TOC andTN was not.A systematic investigation of the bacterial communities was conducted on thesediment from different areas of Lake Taihu, The results suggested thatα-proteobacteria、β-proteobacteria、γ-proteobacteria、δ-proteobacteria and Nitrospirawere the predominant bacteria in the sediment of Lake Taihu; and the diversity ofbacterial was not significantly influenced by the concentration of nutrient elements.the diversity research of anaerobic ammonia oxidation bacteria in the sedimentfrom Lake Taihu showed that the abundance of ANAMMOX bacteria in Meilianglake was higher than that in Zhushan lake. Two ANAMMOX bacteria partialsequences which were reported for the first time were detected and submitted to NCBI(ID: JQ927330、Q927331). Its highest similarity was93%, compared with thepublished sequences.It was revealed that phosphorus in the sediment of Lake Taihu came fromwastewater emission by human activities, but carbon and nitrogen were accumulatednaturally. Lake Taihu had made a transition from natural eutrophication to culturaleutrophication, which was reflected in the sediment. And the structure of bacterialcommunities was not significantly influenced by the concentration of nutrient elements, but by geographical isolation and heavy metal ions. This research hasimportant significance on monitoring pollution、 surveying and making use ofmicrobial resources in Lake Taihu.