不同鱼类和采样时间的养殖池塘环境微生物群落研究

微生物群落是养殖池塘生态系统重要的组成部分。本研究在不同月份采集尼罗罗非鱼和斑点叉尾鮰池塘水体样品,分析水样中的硝酸盐氮、亚硝酸盐氮、氨氮、总氮和总磷等理化指标,利用Biolog-Eco微平板技术分析水体中微生物对各类碳源代谢的平均颜色变化率,利用高通量测序技术分析水体中的菌群结构,以期了解养殖鱼种类和季节对养殖池塘环境及菌群结构的影响。结果表明：冬季淡水养殖池塘水质和菌群结构不同于其他季节,养殖鱼类种类对池塘水体理化指标和水体微生物菌群结构的影响不大。不同采样时间的池塘水体理化指标差异显著,同一采样时间不同养殖鱼类池塘水体理化指标之间无显著差异。其中,1月尼罗罗非鱼养殖池塘水样中的NH4-N含量高于其他月份,显著高于4月和7月的水样(P<0.05)；1月TP含量显著高于1月、4月和7月(P<0.05)。1月斑点叉尾鮰养殖池塘水样中的TP和NO₃-N含量显著高于其他三个月份(P<0.05)。Biolog-ECO微平板技术检测到尼罗罗非鱼和斑点叉尾鮰养殖池塘水样中的微生物群落对碳水化合物和氨基酸的利用能力较强,对酚胺类化合物的利用能力较弱,4月斑点叉尾鮰养殖池塘水体微生物对碳源的利用率高于尼罗罗非鱼养殖池塘。高通量测序结果发现厚壁菌门(Firmicutes)和拟杆菌门(Bacteroidetes)是尼罗罗非鱼和斑点叉尾鮰养殖池塘水体中的绝对优势菌门。hgcI clade、CL500-29 marine group和C39等参与氮磷循环的菌属为淡水池塘养殖水体中的主要菌属。本研究结果为了解淡水养殖环境中微生物群落结构与变化规律、更有针对性的构建淡水养殖池塘尾水生态化处理方法提供科学依据。

Environmental Microbial Community of Different Fish Aquaculture Ponds at Different Sampling Times

The microbial community is of great significance to the maintenance of pond ecosystem. In order to understand the effect of fish species and seasons on water quality and environmental microbial community structure in aquaculture ponds, water samples of Nile tilapia and channel catfish ponds were collected in different months to analyze the contents of total nitrogen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen and total phosphorus. The average well color development (AWCD) of water microorganisms using various carbon sources was analyzed by Biolog ECO-plate technology, and the microbial community structure in water was analyzed by high-throughput sequencing technology. The results showed that the water quality and microbial structure of water in aquaculture ponds in winter were different from those in other seasons, and the species of cultured fish had little effect on the water quality and microbial structure of pond water. There were significant differences in the water qualities of ponds among different sampling times, and there was no significant difference in the water qualities of ponds between tilapia and channel fish at the same sampling time. Among them, the content of NH4-N in water of tilapia ponds in January was higher than that in other months, significantly higher than that in April and July (P<0.05). The content of TP in January was significantly higher than that in January, April and July (P<0.05). The contents of NO3-N and TP in water of channel catfish ponds in January were significantly higher than those in other months (P<0.05). Biolog ECO-plate detected that microorganisms in ponds had high utilization rate of carbohydrates and amino acids and low utilization rate of phenolic amines. In April, the utilization rate of carbon sources by microorganisms in water of channel catfish ponds was higher than that in tilapia ponds. High throughput sequencing showed that Firmicutes and Bacteroidetes were the dominant phylla in tilapia and channel catfish ponds. Hgcl clade, CL500-29 marine group and C39 were the main genera involved in nitrogen and phosphorus cycle in water of freshwater ponds. The results of this study provided a scientific basis for understanding the microbial community structure and variation in aquaculture environment and for constructing targeted method for ecological treatment of waste water in aquaculture.