乌江水质的百分比模式相似性指数评价

Assessment on water quality of Wujiang River by percent model affinity

为了用水生生物生态状况评价乌江的水质情况,在乌江干、支流布置了14个采样断面,以Novak等的百分比模式相似性指数(Percent Model Affinity,PMA)对水电建设期间的乌江下游水质状态进行了评价,并与种类丰富度、EPT%和物种多样性指数相关性分析结果进行了比较。结果表明,支流除郁江水质一般(Moderate)外,其余断面水质处于良好(Good)状态,干流除彭水和洪渡较好外,其余断面水质一般(Moderate)。总体而言,支流水质要好于干流,导致乌江水质恶化的根源主要并不是有机污染,其原因可能与水电工程的建设活动及频繁航运有关。分析表明,百分比模式相似性指数与种类丰富度、EPT%和物种多样性指数相关性均达到显著水平。

In order to assess the water quality by aquatic organisms,14 sampling sections are arranged in the main stem and branches of Wujiang River,and based on the sampled data,the water quality in the downstream of Wujiang River during the hydropower construction period is assessed with Percent Model Affinity（PMA） established by Novak,etc.The assessed results are compared with those by species abundance,EPT% and correlative index of species diversity.The results show that for the branches,except the Yujiang River is moderate,the water quality of other sections is in a good state;the water quality of the mainstream is moderate except that the water quality of Pengshui and Hongdu stations is good.Overall,the water quality of tributaries is better than that of the mainstream.It is revealed that organic pollution is not the main pollution source,whose reason may be the hydropower construction and frequent shipping activities.The analysis shows that the index of PMA has significantly correlation with species abundance,EPT% and correlative index of species diversity.