摘要
为了解鄱阳湖湖区内具有不同形态、功能的沉积物微生物群落的空间差异,采用T-RFLP(末端限制性片段长度多态性)和Biolog-Eco微平板法,对松门山(主湖区)、饶河(入湖口)、南矶山(碟形湖)和白沙洲(湖汊)样地表层沉积物进行细菌遗传多样性和微生物代谢功能多样性进行分析.结果表明:鄱阳湖具有不同形态、功能的样地间细菌群落结构及微生物功能多样性存在协同的空间异质性,显示饶河样地与其他样地之间差异显著(P<0.05).基于T-RFLP结果,饶河样地与其他样地细菌群落结构的差异主要来源于中等相对丰度(0.20%~2.00%)的TRFs片段.此外,饶河样地微生物代谢活性显著低于其他样地(P<0.05),主要是因为饶河样地微生物对多聚物类和碳水化合物类碳源的利用能力显著降低.基于微生物群落与环境因子的冗余分析(RDA)结果显示,营养物质(有机质、TOC、TN)和重金属(Zn)是影响细菌群落结构的主要因子,而水深、pH、速效氮[w(NH_4^+-N)、w(NO_3^--N)]、重金属[w(Zn)、w(Cu)、w(Cd)]是影响微生物代谢多样性的显著因子.研究显示,重金属(Zn)对鄱阳湖沉积物细菌群落结构及微生物功能多样性具有显著影响.研究结果可为探索大型淡水湖泊底栖微生物群落结构和功能的空间异质性以及探讨微生物群落结构与功能对环境因素的响应提供理论依据.
This study aimed to explore the spatial distribution patterns of bacterial community structure and metabolic function in the surface sediments of Poyang Lake using the T-RFLP and Biolog-Ecoplate. Sediment samples were selected from four sites： Songmenshan（ SMS）,Nanjishan（ NJS）,Baishazhou（ BSZ） and Raohe（ RH）. The results demonstrated that both the bacterial community structure and function from RH were significantly different from the other sites（ P〈0. 05）,suggesting a similar spatial variation in both bacterial community and microbial metabolic functions. The T-RFLP fragments with a relative abundance between 0. 20%-2. 00% mainly contributed to the differences of bacterial community composition among the four sites. Meanwhile,the average well color development（ AWCD） used to characterize the microbial carbon metabolic activity of the Raohe samples（ AWCD = 0. 65） was remarkably lower than the other sites（ P〈0. 05）; further analysis attributed this decrease to the reduced utilization of polymers and carbohydrates. Redundancy analysis（ RDA） results showed that nutrient parameters（ i. e.,organic matter,TN and TOC） and heavy metal Zn obviously affected the bacterial community structure,while water depth,p H,available nitrogen（ i. e.,NH4^＋-N,NO3^--N） and heavy metals（ i. e.,Zn,Cu and Cd）had significant effects on the microbial carbon metabolic function. Overall,heavy metal Zn was the most important factor that shaped the bacterial community structure and microbial carbon metabolic function of lake sediments. This study may give insight into the spatial heterogeneity and environmental effects on sediment microbes in large freshwater lakes.
出处
《环境科学研究》
EI
CAS
CSCD
北大核心
2017年第4期529-536,共8页
Research of Environmental Sciences
基金
国家自然科学基金项目(31360127,31060082,31660027)
