Research On The Diversity, Distribution And Abundance Of Anammox Of Sediments From Marine Aquaculture Pond In Jiaozhou Bay

China is now the world's largest fishery nation in terms of total seafood production volume. The rapid development of marine aquaculture in China caused heavy ammonia accumulation which not only is toxic to the cultured animals and also induced serious eutrophication and destruction to the surrounding marine environment. Anammox (anaerobic ammonia oxidizing) bacteria have the ability of transforming ammonia and nitrate into N2 in anoxic conditions, reducing the ammonia in aquaculture environment and maintaining the smooth circulation of nitrogen in farming. To understand the impact of the hypernutritional marine aquaculture to the community structure of anammox bacteria, we use the functional gene hzo (hydrazine-oxidizing enzyme) to study the diversity, spatial distribution and abundance of Anammox bacteria.Six hzo gene libraries for Anammox were constructed. Through RFLP (Restriction Fragment Length Polymorphism) analysis, 625 clones and 104 OTUs (Operational taxonomic units) were identified. The similarity of hzo gene most similar sequences with the GenBank database is 84% to 100%. Station L3 showed the highest diversity, while the station L4 lowest. The Jackknife Cluster and the PCoA cluster analysis of Anammox bacterial community showed two groups. The inside station L2 and L3 were grouped in to the polluted group, and L1, L4, L5 were grouped into the cleaner one. This result was consistent with the environmental classification, indicates that the Anammox significant adaptive environmental conditions in the spatial distribution, and also suggests that hzo gene can be used as indicators of environmental pollution and tracer. The combination of physiochemical and sedimental parameters contributed to the Anammox niche adaption. Phylogenetic tree was divided into six Cluster. Two branches, "Candidatus Scalindua" and "Candidatus Scalindua-like", were dominant in the marine aquaculture sediment. The highest hzo gene copy number was found in station L2 (1.255×10⁶ copies/g), while station L5 was lowest (1.257×10⁵ copies/g). The relative abundance were parallel to the former results, station L2 was the highest (1.1975×10^-5) and station L5 lowest (1.3693×10^-6). Further studies on the RNA transcriptional level should be done to reveal the key environmental factors which influence the hzo abundance and anaerobic activities of Anammox.Nitrogen pollution is the most important factor which impacts the genetic diversity of anaerobic ammonia oxidizing bacteria. Our research showed significantly values in revealing the Anammox diversity and the correlationship of environmental parameters and Anammox community structure, and would provide the theoretic support to the nitrogen pollution management in hypernutritional marine aquaculture system.