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为了解凡纳滨对虾(Litopenaeus vannamei)养殖过程中挂膜式生物滤器内不同位置间微生物群落结构多样性的差异,采集已运行46 d的挂膜式生物滤器内挂膜上部外侧和内侧、下部内侧和外侧及收集盘5个不同位置的微生物,采用分子生物学手段,通过16S r RNA基因高通量测序法对生物滤器内微生物进行多样性分析,并对不同位置间功能性微生物进行对比。结果显示,在门水平上,5个不同位置共鉴定出10个主要类群,其中,变形菌门(Proteobacteria)所占丰度比例较大,为主要优势类群,硝化螺旋菌门(Nitrospirae)在挂膜内外两侧检出比例均较高(平均4.3%),收集盘内则较低(0.33%),存在显著性差异。共鉴定出41种优势属,其中地杆菌属(Pedobacter)为绝对优势种属,短小盒菌属(Parvularcula)为次优势属,二者丰度比例均在10%以上,硝化螺旋菌属(Nitrospira)为第三优势属,挂膜不同位置丰度比例(平均4.31%)显著高于收集盘内比例(0.28%)。挂膜上氨氧化细菌(AOB)平均丰度比例为1.70%,硝化细菌(NOB)平均比例为6.99%,是系统中主要去除氨氮和亚硝酸氮的微生物。生物滤器各部位微生物物种多样性丰富,微生态系统稳定,可有效维持循环水系统的水质。生物滤器硝化作用主要在上部进行,下部净化能力较弱,收集盘内基本没有硝化能力。生产中应合理配置挂膜数量,科学设计挂膜长度以提高生物滤器的净化效率。
In order to understand the difference of microbial community structure diversity between different positions in the biofilter in the culture of Litopenaeus vannamei, the outer and inner sides of the upper part of the hanging membrane and the inner part and the lower part of the hanging membrane were collected for 46 days Inside and outside of the collection tray and five different locations on the collection tray. By means of molecular biology, 16S rRNA gene high-throughput sequencing was used to analyze the diversity of microorganisms in the biofilter and to compare the functional microorganisms in different locations. The results showed that 10 major groups were identified at five different locations at the gate level. Among them, Proteobacteria accounted for a large proportion of the dominant groups, with Nitrospirae hanging The detection rate was high on both the inside and outside of the membrane (average 4.3%), while it was lower (0.33%) in the collection tray. There was a significant difference. A total of 41 dominant genera were identified, of which Pedobacter was the dominant species, Parvularcula was the dominant genera, and the abundances of both were above 10%. Nitrospira ) Is the third dominant genus, and the ratio of abundance at different positions (4.31% on average) is significantly higher than that on the collection plate (0.28%). The average abundance ratio of ammonia-oxidizing bacteria (AOB) on the membrane was 1.70%. The average proportion of nitrifying bacteria (NOB) was 6.99%, which was the main microorganism that removed ammonia nitrogen and nitrite nitrogen in the system. Microbial species diversity in various parts of the biological filter, micro-ecosystem stability, can effectively maintain the water quality of the circulating water system. Biological filter nitrification is mainly carried out in the upper part of the lower purification capacity is weak, the basic collection of nitrification capacity. Production should be a reasonable allocation of the number of hanging membrane, the length of the scientific design of the hanging membrane to improve the biological filter efficiency.