利用水生生物指标识别滇池流域入湖河流水质污染因子及其空间分布特征

入湖河流作为连接湖泊流域"源"(陆地)-"汇"(湖体)的廊道,其水生态系统健康状态是对流域上游陆地生态系统土地利用/覆被变化的响应,而其下游水质污染因子则因流域分水线的封闭性,可以表征上游土地利用/覆被变化对入湖河流水生态系统健康的影响.因此,利用水生生物指标识别入湖河流水质污染因子及其空间分布特征,对于整个湖泊流域的...

Identification of water pollution factors and their spatial distribution with aquatic bioindicators in streams of Lake Dianchi watershed

In the lake watershed, streams are important landscape corridors that link the source (land) and the sink (lake). The ecosystem health of streams is usually used to indicate the aquatic biodiversity of the lake ecosystem, as well as being affected by water pollution factors in response to changes in land use cover of the terrestrial ecosystem due to natural geographic characteristics of the watershed with the closure of ridge lines. Therefore, identification of the water pollution factors with aquatic bioindicators has a good effect on the restoration of aquatic ecosystem health and the control of the total water pollution in the lake watershed. Using mensal physical-chemical parameters of the 29 streams of Lake Dianchi watershed in 2009 and the survey data of periphytic algae and macrozoobenthos during July and August, 2009, factor analysis, canonical correspondence analysis and hierarchical cluster analysis were used to identify the community of aquatic bioindicators and the key water pollution factors and their spatial distribution. The results identified 5 divisions, 18 families, and 24 genera of periphytic algae. Among these, Navicula (Bacillariophyta) was the dominant genus. Besides, 3 divisions, 7 families, and 8 genera of macrozoobenthos were identified. Limnodrilus (Annelida) was the dominant genus. TN, NH3-N, and TP were the key water pollution factors, and were significantly correlated with the aquatic bioindicators. The spatial distribution of density of aquatic bioindicators and water pollution was both greatest in the streams flowing into the north lake(River Wangjiaduiqu, River Xinyunlianghe, River Laoyunlianghe, River Wulonghe, River Daguanhe, River Xibahe, River Chuanfanghe, River Cailianhe, River Jinjiahe, River Panlongjiang, River Daqinghe, River Haihe, River Liujiabaoxianghe, River Xiaoqinghe, River Wujiabaoxianghe, River Xiabahe, River Laobaoxianghe, River Xinbaoxianghe, and River Maliaohe),followed by those flowing into the south lake(River Nanchonghe, River Yunihe, River Laochaihe, River Baiyuhe, River Cixianghe, River DongDahe, River Zhonghe and River Guchenghe), and least in those flowing into the east lake(River Luolonghe and River Laoyuhe).