汉江上游金水河流域水电工程对流域水环境的影响

通过监测和实地调查,分析了汉江上游金水河流域水电工程对流域水环境的影响。结果表明：①电导率（EC）、总溶解性固体（TDS）、五日生化需氧量（BOD5）、重碳酸盐（HCO-3）、硫酸盐（SO42-）、总硬度（T-Hard）、溶解性金属元素Si、正磷酸盐（PO43--P）、总溶解性磷（TDP）的监测值季节性变化不显著;②化学需氧量（CODMn）、溶解性重金属元素Cr和As、营养物质PO43--P和TDP的含量在不同采样时期均不同程度的超标;③作为控制河流水化学特征的重要因素,水温（Temp）、pH值与溶解氧（DO）分别与水环境中EC、TDS、CODMn、HCO-3、氯化物（Cl-）、硝酸盐（NO-3）、氟化物（F-）、As、Cr、Si、氨氮（NH＋4-N）、硝酸盐氮（NO-3-N）和PO43--P的监测值呈显著的线性相关。已建成的水电工程在一定程度上破坏了流域的连续性,减少了水体纳污能力,降低了河流水质。因此,在研究的基础上,提出解决水电开发与环境保护之间矛盾的合理建议,为汉江上游的流域生态系统管理提供依据。

Impact of hydropower project on water environment of Jinshui river basin in upper reaches of Hanjiang River

Through monitoring and field survey,the paper analyzed impact of hydropower project on water environment of Jinshui River basin in the upper reaches of Hanjiang River. The results indicated that ①the variations of monitoring value of electrical conductivity（ EC）,total dissolved solids（ TDS）,five day biological oxygen demand（ BOD5）,bicarbonate（ HCO-3）,sulfate（ SO4 2-）,total hardness（ T- Hard）,dissolved Si,orthophosphate（ PO4 3--P） and total dissolved phosphorus（ TDP） are not significant on season. ②The values of chemical oxygen demand（ Mn）（ CODMn）,dissolved Cr and As,nutrient matters of PO4 3--P and TDP have exceeded the guidelines in different sampling periods and extents. ③As the main factors of controlling the hydrochemical characteristics of the river,the monitoring values of water temperature（ Temp）,pH,and dissolved oxygen（ DO） are linearly correlated with EC,TDS,CODMn,HCO-3, chloride（ Cl-）,nitrate（ NO-3）,fluoride（ F-）,As,Cr,Si,ammonical nitrogen（ NH＋ 4-N）,nitrate nitrogen（ NO-3-N） and PO4 3-P present significant linear correlation respectively. The completed hydropower projects damaged the continuity of watershed to a certain extent and reduced the capacity of pollutant carrying of water body and deteriorated the water quality of river. Accordingly,the paper put forward some reasonable suggestion so as to resolve the conflicts between hydropower development and environmental protection,which can provide the basis for watershed ecosystem management of the upstream of HanJiang river.