大口黑鲈池塘工程化循环水养殖系统的溶解氧时空变化及菌群响应特征

采用基于Illumina Miseq测序平台的高通量测序技术, 从不同角度(密度、区域、溶氧、季节)分析大口黑鲈(Micropterus salmoides)池塘工程化循环水养殖系统中溶解氧和水温对细菌群落结构和丰富度的影响。结果表明: 菌群丰富度在9月份最高, 在10月份最低。在昼夜变化中, 溶解氧最低时的菌群丰富度整体上高于溶解氧最高时。在不同区域中, 粪便收集区的菌群丰富度高于养殖区。在7—11月份的季节变化中, 变形菌、放线菌、拟杆菌和蓝细菌的相对丰度占据前四位; 在属水平上, 假单胞菌、黄杆菌和聚球菌为优势物种; 几乎每种细菌都具有显著或极显著的月份差异。假单胞菌的相对丰度与溶解氧和水温皆具有极显著的相关性。聚球菌、蓝细菌、CL-500_marine_group和Alpinimonas皆与水温具有极显著相关性。分枝杆菌、MNG7与溶解氧极显著相关。此外, 不同菌群之间也具有显著或极显著的相关性。实验结果表明放养密度、养殖区域、溶氧浓度和季节变化都会影响水体菌群丰富度。

TEMPORAL AND SPATIAL VARIATION OF DISSOLVED OXYGEN AND REACTION OF BACTERIAL COMMUNITY IN IN-POND RACEWAY SYSTEM (IPRS) OF LARGEMOUTH BASS (MICROPTERUS SALMOIDES)

This study analyzed the effects of dissolved oxygen content (DOC) and water temperature on the community and richness of bacteria in In-pond Raceway System (IPRS) from various viewpoints using Illumina Miseq high-throughput sequencing technology. The highest and lowest microbial richness was in September and October, respectively. In general, the microbial richness in lowest DOC was greater than that in highest DOC during the diurnal variation. The microbial richness in fecal collecting area was greater than that in aquaculture area. Proteobacteria, Actinobacteria, Bacteroidetes and Cyanobacteria were the 4 dominant species among July and November. At generic levels, Pseudomonas, Synechococcus and Flarobacterium were dominant species. Almost every bacterium had significant or extremely significant difference among different months. The richness of Pseudomonas was positively correlated to DOC (r=0.415, P<0.01), but negatively correlated to water temperature (r=–0.427, P<0.01). There was a significant correlation between Synechococcus, Cyanobacteria, CL500-29, Alpinimonas and water temperature (r=0.636, –0.448, 0.755, –0.428 respectively, P<0.01). The richness of Mycobacterium (r=0.488, P<0.01) and MNG7 were significantly correlated to DOC. Furthermore, there were significant or extremely significant relations among different bacterial communities. The microbial richness increased with the decreasing DOC level to reach peak level at 2.5 mg/L of DOC. These results suggest that stocking density, culture area, DOC, and season variety could regulate microbial richness.