温榆河浮游动物多样性及水质改善效果评价

为评价自2010年5月罗马东湖示范工程运行后温榆河水质变化情况,于2010年5月-2011年2月间,定期采集该流域大型浮游动物,并从浮游动物种类、敏感种数量以及Shannon-Weaver生物多样性指数(H')等3个方面对温榆河流域大型浮游动物多样性进行分析。2010年5月-10月,罗马东湖大型浮游动物种类增加,敏感种数量上升,Shannon-Weaver生物多样性指数(H')由0.650 1升至2.134 2,水质由重污型改善为β-中污型;2010年11月-2011年2月,H'降低,说明季节变化对生物多样性影响较大。下游苇沟桥由于接受示范工程水域敏感种,H'与罗马东湖具有相同变化趋势,但受到清河水体影响,实际水质较差。苇沟桥下游北关闸敏感种再次消失,H'降低。其他位点H'明显较低,并受季节变化影响。结果表明:温榆河水质改善示范工程对局部水域的水质改善效果明显。要实现河流健康目标,必须控制污染源,由点到面,逐步由局部生态修复过渡到流域生态系统的恢复。

Evaluation of Water Quality Improvement in Wenyuhe River Based on the Analysis of Diversity of Macro-zooplankton

The analysis of diversity index of macro-zooplankton in Wenyuhe River with Shannnon-Weaver diversity index(H’),zooplankton species and sensitive species from May 2010 to February 2011 was carried out after the demonstration project.The amount of zooplankton in Roma East Lake where the demonstration project was running increased evidently,and the number of sensitive species rose.Shannon-Weaver diversity index(H’) changed gradually from 0.650 1(serious pollution type)in May to 2.134 2(medium pollution of β type) in October,and it showed the rule of seasonal change.Though H’ of Weigou Bridge downstream increased due to H’ of Roma East Lake,which showed the same trend as Roma East Lake,the water quality was poor due to the water pollution of Qinghe River.H’ of Beiguan Brake downstream of Weigou Bridge decreased evidently.The results suggested that the artificial demonstration project of Roma East Lake had positive effects on the improvement of water quality.However,some other measures must be taken to control the pollution source to realize the targets of overall improvement of water quality in Wenyuhe River.