大水面放养水葫芦对富营养化湖泊水体可培养细菌群落结构的影响

Effect of large-scale planting water hyacinth on cultivable bacterial community structure in the eutrophic lake

摘要:

【目的】了解大水面放养水葫芦对富营养化湖泊水体可培养细菌群落结构和多样性的影响。【方法】采用稀释平板法，分别对云南滇池紫根水葫芦放养区(ZW)、野生型普通水葫芦放养区(PW)、未放养水葫芦对照区(CK)水体中细菌进行分离，并对其16S rRNA序列进行分析。【结果】 分别从ZW、PW、CK 3种水体分离得到54、49、40株菌落形态差异的细菌，Shannon-Wiener多样性指数分别为3.17、3.07、2.73，细菌数量分别为1.35′107、8.35′106、2.70′106 CFU/L。16S rRNA序列分析表明，ZW、PW、CK 3种水体可培养细菌主要包括变形菌门α亚群(Alphaproteobacteria，35.1%、32.4%和40%)、放线菌门(Actinobacteria，18.9%、32.4%和20%)、变形菌门β亚群(Betaproteobacteria，13.5%、5.9%和16.0%)、变形菌门γ亚群(Gammaproteobacteria，13.5%、14.6%和12.0%)、拟杆菌门(Bacteroidetes，13.5%、8.8%和8.0%)和厚壁菌门(Firmicutes，2.7%、5.9%和4.0%)。在属的水平上，3种水体仅有鞘氨醇盒菌属(Sphingopyxis)、红细菌属(Rhodobacter)、黄色杆菌属(Xanthobacter)、新鞘脂菌属(Novosphingobium)、鞘氨醇单胞菌属(Sphingomonas)、假单胞菌属(Pseudomonas)、微杆菌属(Microbacterium)、链霉菌属(Steptomyces)、黄杆菌属(Flavobacterium)、芽孢杆菌属(Bacillus)等10个属的细菌为共有菌属。【结论】大水面放养水葫芦提高了富营养化湖泊水体中可培养细菌的多样性，改变了细菌的群落结构。

Abstract:

[Objective] To investigate the impact of large-scale planting water hyacinth (Eichhornia crassipes) on the cultivable bacterial community structure and diversity in the eutrophic lake. [Methods] Diluting plate counting method was applied to monitor the cultivate bacteria communities in three water hyacinth planting areas composed of purple root water hyacinth planting area (ZW), wild-type water hyacinth planting area (PW) and non-planting sites (control, CK), and then the 16S rRNA gene of the isolates were sequenced. [Results] 54, 49 and 40 isolates with various morphological characteristics were obtained from ZW, PW and CK, respectively. The Shannon-Wiener diversity indexes were 3.17, 3.07 and 2.73, respectively. And the quantities of the culturable bacterial in ZW, PW and CK were 1.35′107 CFU, 8.35′106 CFU, 2.70′106 CFU of per Liter, respectively. The 16S rRNA sequencing result showed that at the common and dominant phylum species among the three sampling sites were Alphaproteobacteria, which accounting for 35.1%, 32.4% and 40.0% of total culturable bacteria, and Actinobacteria which accounting for 18.9%, 32.4% and 20.0%, and Betaproteobacteria which accounting for 13.5%, 5.9% and 16%, and Gammaproteobacteria which accounting for 13.5%, 14.6% and 12.0%, and Bacteroidetes which accounting for, 13.5%, 8.8% and 8.0%, and Firmicutes which accounting for 2.7%, 5.9% and 4.0%, respectively. Only ten genera Sphingopyxis, Rhodobacter, Xanthobacter, Novosphingobium, Sphingomonas, Pseudomonas, Microbacterium, Steptomyces, Flavobacterium and Bacillus were shared by all the three water samples. [Conclusion] This study indicates that large-scale planting water hyacinth could both increase the cultivated bacterial diversity and modify the bacterial community composition in the eutrophic lake.