辽河浮游植物群落及生物多样性基准验证

Phytoplankton community and validation of phytoplankton biodiversity criteria in Liaohe River

为建立中国水环境生态学基准体系，并验证其合理性，于2011和2012年夏季，对辽河水系浮游植物群落结构特征进行了调查，并结合所收集到的资料，初步验证了辽河水系浮游植物生物多样性基准值的合理性．两次采样共检出6门169种及变种；细胞密度均值分别为4．91×10^6,7．04×10^6个／L，优势类群为硅藻和绿藻．共检出污染指示种59种，其中乙型中污指示种最多，为53种；检出优势种35种，主要为硅藻．综合各生物指标显示辽河水系夏季为富营养型中度污染水体．Shannon指数（邱在1．18-3．56之间，均未达到本文参考的基准值3．65，分析结果显示用于计算基准值所选取的参照点较为合适，通过分析辽河水系及我国其他一些河流的Shannon指数与水质状况，初步认为，该基准值偏高，建议辽河水系设定基准值的下限H=3．29．

To establish Chinese water environment ecological criteria and to validate its reasonableness, an investigation was conducted on the phytoplankton community structure in Liaohe River water system in summers of 2011 and 2012. with other recults refered, the reasonableness of phytoplankton biodiversity criteria was validated preliminarily. The 169 phytoplankton species were recorded in all of the samples; the mean cell density was 4.91×10^6cells/L in 2011 and was 7.04×10^6cells/L in 2012, and dominated by Bacillariophyta and Chlorophyta. The 59 indicator species of water pollution were detected and most of them were offl-mesosaprobic; The 35 dominant species were found and many of them were Bacillariophyta. All of these biological indicators showed that the Liaohe River water system was in eutrophication and at moderate polluted level in the summers. The Shannon index （H） was between 1.18 and 3.56, less than the proposed criteria value of 3.65 previous. The analysis showed the reference sites for calculation of the ecological criteria were appropriate. Considering the H and water quality of the Liaohe River water system and some other rivers, the proposed criteria value was a little higher, so it was recommended to set the lower limit H = 3.29 in Liaohe River water system.