城市缓流水体生物膜群落与环境因子响应关系

Relationship between the biofilm microbial communities and the environmental factors of municipal slow-flow water

以南京市秦淮河、石头城护城河、乌龙潭、玄武湖4个水体为研究对象,采用磷脂脂肪酸（PLFA）法对城市缓流水体生物膜群落特征进行分组研究.通过SPSS、CANOCO软件分析水体生物膜群落与环境因子的响应关系,结果表明：（1）温度及水体营养盐含量的降低会导致水体微生物新陈代谢缓慢,微生物大量死亡.静态水体生物膜中微生物量的变化范围是9.16×10^6~2.74×10^8cells/g,流动水体生物膜中为1.69×10^7~7.77×10^7cells/g,静态水体中生物量的下降趋势比流动水体中显著,可能是由于水体的流动加强了营养盐在固液相之间的质量传递,削弱了水体温度及营养盐含量变化对流动水体生物膜中微生物生长的影响程度.（2）功能菌群G-、G＋、真菌是微生物菌群的主要成分,3者比重为：G-〉真菌〉G＋.随温度的降低（T≥8.4℃）,静态水体中主要功能菌群总含量变化波动较大,其波动范围为27.41%~66.20%,流动水体中主要功能菌群总含量的变化范围较小,为43.09%~68.25%,差异的主要贡献者是G-和真菌.（3）静态水体中环境因子温度、硝态氮、COD是功能菌群的主要影响因子,氮元素是流动水体中功能菌群的显著影响因子.

The objective of this paper was to study the biofilm microbial communities from Qinhuai River,Stone town moat,Lake Wulong and Lake Xuanwu of Nanjing using phospholipid fatty acid（ PLFA） method.（ 1） It was found that the decreasing of temperature and nutrients concentration led to the slowing down of the metabolism rate and even the death of microorganisms. The microbial biomass ranged from 9. 16 × 10^6 to 2. 74 × 10^8 cells / g in static water,while in running water,it ranged from 1. 69 × 10^7to7. 77 × 10^7 cells / g. The decline of microbial biomass in static water could be attributed to the higher transfer resistance.（ 2） G-,G＋ and fungi mainly comprised the microbial community in the order： G-〉 fungi 〉G＋. As temperature decreasing（ T ≥8. 4℃）,the content of functional bacteria in static water fluctuated from 27. 41% to 66. 20%,while in running water it fluctuated from 43. 09% to 68. 25%. The difference might be caused by G-and fungi.（ 3） In static water,temperature,concentration of nitrate and COD largely influenced the growth of functional bacteria,while in running water the concentration of nitrogen was critical.