池塘水体氨氧化细菌季节变化及其与环境影响因子相关性分析

以氨氧化细菌(AOB)的氨单加氧酶amoA基因为分子标记,调查了湖北省公安县崇湖渔场草鱼池塘水体AOB季节变化,并分析了AOB丰度与主要环境因子的相关性.结果表明,池塘表、底层水体AOB amoA基因拷贝数均呈相似的季节变动规律,即夏季显著高于春、秋两季(p0.05),而春、秋两季间无显著差异(p0.05);相同季节池塘表、底层水体AOB amoA基因拷贝数无显著性差异(p0.05).表、底层水体AOB amoA基因拷贝数均与温度、总磷呈显著正相关;与溶解氧呈显著负相关.此外,表层AOB amoA基因拷贝数与总有机碳呈极显著负相关.主成分分析将8个环境因子划分为3个主成分.表层第一主成分为水温、溶解氧、氨氮与总磷,第二主成分为硝态氮与总有机碳,第三主成分为总氮与亚硝态氮;底层第一主成分为水温、溶解氧、氨氮、总磷与总有机碳,第二主成分为硝态氮与亚硝态氮,第三主成分为总氮.

Correlation analysis between the seasonal variations of abundance of ammonia-oxidizing bacteria and environmental factors in ponds

This study investigated the seasonal variations of abundance of ammonia-oxidizing bacteria (AOB) and the relationship between the abundance of AOB and environmental factors in different grass carp ponds by using the functional gene amoA as a molecular marker. The target ponds were located in Chonghu fishery farms, Gong''an County, Hubei province. The results show the similar results in different ponds. Higher copy numbers of AOB amoA gene were observed in summer (p<0.05), while no significant differences were detected in spring and autumn (p>0.05). There was no significant difference between AOB abundance at the surface and bottom layer in the same season (p>0.05). The AOB abundance at the surface and bottom layer were positively correlated with temperature and total phosphorus, but negatively correlated with DO. Furthermore, the surface AOB abundance was negatively correlated with total organic carbon. The principal component analyses (PCA) show that the eight environmental factors were grouped into three PCAs. At the surface layer, PCA1 included temperature, DO, ammonia nitrogen and total phosphorus, PCA2 included nitrate nitrogen and total organic carbon, PCA3 included total nitrogen and nitrite nitrogen. At the bottom layer, PCA1 included temperature, DO, ammonia nitrogen, total phosphorus and total organic carbon, PCA2 included nitrate nitrogen and nitrite nitrogen, PCA3 included total nitrogen.