【摘要】 探究浮床空心菜种植对罗非鱼养殖池塘水体微生态环境的影响方式，采用10%的浮床覆盖率进行空心菜种植作为处理塘，在空心菜旺盛生长以后，分别采集池塘水、对照塘水和空心菜根系样品，提取样品DNA，一部分进行细菌16S rRNA基因PCR扩增和高通量测序，研究其细菌群落结构，分析浮床空心菜对水中细菌群落结构的影响，分析空心菜根系和所在水中细菌群落结构的关系，另一部分采用荧光定量PCR方法测定固氮酶基因拷贝数，分析浮床空心菜对水体固氮酶基因的影响。结果表明，浮床空心菜种植对水中浮游细菌群落结构的直接影响不显著，空心菜根系生物膜作为池塘微生态环境重要组成部分发挥作用。空心菜根系生物膜还同时增加了池塘单位水体固氮微生物的数量。更多还原

【Abstract】 In order to explore the way of water spinach planting in floating bed affecting the water microecological environment of tilapia aquaculture ponds, water spinach floating beds were set up in the ponds under the 10% coverage. These ponds served as the treatment group, while the other ponds without floating beds served as the control group. After the vigorous growth of water spinach, the samples of water from treatment ponds, control ponds, and the samples of water spinach roots were collected respectively. The DNA of the samples was extracted, part of them was used to amplify the 16S rRNA genes and carry out the highthroughput sequencing, to investigate the effect of water spinach planting on the bacterial community structure in water, and analyze the relationship between the root system of water spinach and the bacterial community structure of surrounding water. Another part of DNA was used to conduct the fluorescent quantitative PCR to determine the copy number of nitrogenase gene, and analyze the effect of water spinach planting on the nitrogenase genes in tilapia aquaculture pond ecosystems. The results showed that the direct effect of water spinach planting on the community structure of planktonic bacteria in the water was not significant; however,the root biofilm of water spinach played an important role as a key part of the pond micro-environment. At the same time, water spinach root biofilm also increased the number of nitrogen-fixing microorganisms per unit volume in pond water.更多还原