补给水质与社会活动对白洋淀湿地微生物的影响特征

Effects of Water Supply Quality and Social Activity on the Microbial Community in Baiyangdian Wetland

为了阐明白洋淀湿地补水水质与社会活动对湿地生物群落的影响,研究了淀区不同区域水体中细菌、真菌和古菌群落的变化特征.分别在淀区入口的府河(NBB)、人类社会活动频繁旅游区域(NBD)和居民生活养殖区域(NBX)以及村庄稀疏区域(NBN)采集样品,对样品的理化特征及生物群落进行研究.结果表明,在NBB水体中有机污染物COD浓度为12.35mg·L^(-1),总氮浓度为10.12 mg·L^(-1),污染物浓度较高;NBD和NBX水体中污染物比NBB少.NBN水质较好,其COD和总氮浓度分别为6.9 mg·L^(-1)和1.82 mg·L^(-1).NBB细菌种类较多,多样性指数为5.86,NBN最少为4.78.所有样品中优势细菌菌群均为变形菌门,该菌门在NBN样品中占细菌群落总数的68.8%.真菌在NBB中多样性指数仅为2.14,NBN真菌种类较多,多样性指数为3.23,在NBD和NBN出现壶菌门,分别占真菌总数的5.4%和9.8%,该菌群是难降解有机碳的主要分解者.在NBN中古菌多样性偏低,所有样品中泉古菌门(Crenarchaeota)为优势门类,在NBB、NBD、NBX和NBN样品中所占比例分别39.0%、51.9%、47.3%和30.1%,其次为盐杆菌门(Halobacterota).白洋淀湿地水体富营养化及微生物群落变化的主要因素是外源污染与内源污染共同作用结果,外源污染与内源污染使水体中有机物与氮磷含量增加,微生物群落结构发生了明显改变.

To clarify the impact of water quality and social activity in the Baiyangdian wetland on the biological community,the change characteristics of bacterial,fungal,and archaeal communities in different areas of the Dian District were studied. Samples were collected at the entrance of Fuhe District( NBB),tourist areas with frequent human social activities( NBD),residential breeding areas( NBX),and village sparse areas( NBN). The physical and chemical characteristics and biological communities of the samples were evaluated. The results of the study show that the COD concentration of organic pollutants in the NBB was 12. 35 mg·L^(-1),and the total nitrogen concentration was 10. 12 mg·L^(-1),that the concentration was highest. Moreover,the water quality in NBD and NBX was better than that of NBB. The NBN area exhibited the best water quality,with COD and total nitrogen concentration values of 6. 9 mg·L^(-1) and1. 82 mg·L^(-1),respectively. Many types of NBB bacteria were recorded,with a diversity index of 5. 86,and NBN diversity index exceeding 4. 78. The dominant bacterial flora in all samples was the Proteobacteria,which accounts for 68. 8% of the total bacterial communities in NBN samples. The diversity index of fungi in NBB was only 2. 14. There were many types of fungi in NBN,with a diversity index of 3. 23. Chytridiomycota was found in the NBD and NBN,accounting for 5. 4% and 9. 8% of the total number of fungi,respectively. The Chytridiomycota was main decomposer of hard to degrade organic carbon. The diversity of archaea of NBN was the lowest among all the samples. Crenarchaeota was the dominant phylum,which accounts for 39. 0%,51. 9%,47. 3%,and 30. 1%of NBB,NBD,NBX,and NBN samples,respectively. The number of Halobacterota was lower than Crenarchaeota. The main factor of eutrophication and microbial community changes in Baiyangdian wetland was the results of the combined action of external and internal pollution. Both external and internal pollution increased the organic matter,nitrogen and phosphorus content in the water,and the microbial community structure has changed significantly. The contents of organic matter,nitrogen,and phosphorus in water were increased and the microbial community structures were changed significantly by the increase of both external and internal pollution.