环境因子对河流回水区水体富营养化影响的研究综述

Review of research on different environmental factors' influence on the eutrophication in backwater region of rivers

水体富营养化多发生于湖泊水库等缓流水域,其中部分河流具有较长的回水区,由于其流速较缓,常年处于水库状态,对污染物质的扩散和自净能力低。在营养盐富集的情况下,其不利的水文条件增大了水华现象发生的可能性。特别是自三峡水库建成蓄水以来,干流流速明显减缓,水体自净能力大幅下降,库区多条次级河流的回水区都已经出现了藻类异常繁殖的现象,因此河流回水区水质值得我们关注。通过综述不同环境因子,包括营养盐、水温、光照强度、pH值、水动力条件对河流回水区水体富营养化的影响,继而提出防治河流回水区富营养化的措施及建议。

The eutrophication happens occurs mostly in waters with slow flowing water such as lakes and reservoirs; parts of the rivers have long backwater reaches,which result in the slow stream velocity and the reservoir state of the water; the pollutant diffusion and self-purification ability in these areas are low. In the case of the nutrient enrichment,the disadvantageous hydrological conditions increase the likelihood of water bloom. In particular,since the water storage of Three Gorges Reservoir,the main stream velocity slows significantly down and the water self-purification ability has fallen sharply,with abnormal growing of algae in many secondary rivers' backwater reach in the reservoir; consequently,the water quality of the backwater reaches deserves much attention. Through the review of different environmental factors' influences,including nutrients,water temperature,light intensity,pH values,hydrodynamic force conditions,on the eutrophication in the backwater reach of rivers,this paper proposes measures and suggestions for the prevention and control of eutrophication in backwater reaches.