官厅水库水质特征及水体微生物多样性的响应

针对北京市原水源地官厅水库,选择了上下游共6个采样点进行了不同季节的水质及环境因子特征分析.总体看来,4个季节水体氮磷碳营养物质浓度依次为:夏季秋季春季冬季,夏秋季出现明显水华.上游妫水河水质要好于下游水库库区水质,尤其以夏秋季节最为明显.夏季上游妫水河的总碳、总氮、氨氮、总磷平均浓度为26.5,0.95,0.55,0.077mg/L,而水库库区响应平均浓度分别为111.47,4.27,3.16,0.25mg/L.结合PCR-DGGE对不同时期各点水体微生物进行了群落分析,发现上下游水体中细菌群落结构差异很大,水华严重区的细菌群落多样性和丰度要低于比水质较好区域.CANOCA软件分析了夏秋季水华时水体微生物群落变化与环境因子的响应关系,发现细菌群落结构与环境因子(T、p H值、DO、NFR、TP、Fe)之间存在较强的关联.水质较好的上游水体夏秋细菌群落结构主要受温度、DO影响较大;而水质较差的库区水体夏秋季细菌群落结构变化与固氮速率、p H值、总磷的相关性较好.

The corresponding of microbial diversity on water quality and environmental variables of Guanting Reservoir

The water quality and environmental factors of Beijing Guanting Reservoir in different seasons were analyzed based on the characterization of the data from six sampling sites. Generally, the concentrations of the nutrients including carbon, nitrogen, and phosphorus were in the orders of: summer > autumn > spring > winter, and the outbreaks of water-blooms occurred in summer and autumn. The water quality in the upstream (Gui River), was better than that of the downstream (reservoir area), especially in summer and autumn. In summer, the average concentrations of total carbon, total nitrogen, ammonia nitrogen, total phosphorus in upstream were 26.5, 0.95, 0.55, 0.077mg/L respectively, while that of downstream were 111.47, 4.27, 3.16, 0.25mg/L respectively. Microbial community of the water was analyzed employing PCR-DGGE technique. The result showed that bacterial community structures varied considerably between the upstream and the downstream. The upstream water behaved the higher level of bacterial community diversity and richer degree than that of downstream water serious bloom area. In addition, CANOCA software was used to explore the response relationship between microbial community and environmental factors in summer and autumn bloom periods. The result showed strong correlation in response of bacterial community structure with environmental factors (T, pH, DO, NFR, TP, Fe). For upstream water, the better water quality was in the bacterial community structures mainly affected by the temperature and DO factor; while for the downstream, the poor water quality was with the bacteria community structures effected mainly by environmental factors of pH, TP and NFR.