渭河流域河流健康调查与评价

在渭河流域开展野外采样调查,并采用水文改变指标法、综合水质标识指数法、生物完整性指数法等分析和评价渭河流域的水文、水质和水生态现状。结果表明:(1)林家村、魏家堡和咸阳3个站点的水文情势改变程度为高度改变,而临潼、华县的水文情势改变程度为中度改变;(2)渭河流域丰水期水环境质量状况优于枯水期,影响渭河水系的主要环境因子为总氮(TN)和总磷(TP),影响泾河和北洛河水系的主要环境因子为电导率;(3)渭河流域鱼类和底栖动物在丰、枯水期的生物完整性差异较小,着生藻类在丰、枯水期的生物完整性差异则较大。提出以下建议:(1)控制水利工程的过量开发利用,合理调控闸坝的蓄放水过程;(2)在河道沿岸建设污水处理厂,对排河污水进行拦截和处理,并定期监测水体理化性质,重点关注TN、TP和电导率;(3)控制渭河流域内的石油开发强度,恢复河岸带及边坡生境,以保证水生生物的正常栖息和繁衍。

Investigation and assessment on river health of Weihe River Basin

Field sampling survey was conducted in Weihe River Basin, and methods such as indicators of hydrologic alteration, comprehensive water quality identification index and index of biotic integrity were applied to analyze the status of hydrological, water quality and water ecology of Weihe River Basin. The results show that the hydrological regimes at Linjiacun, Weijiapu and Xianyang have been markedly altered, while those at Lintong and Huaxian have been moderately altered. The water quality of Weihe River Basin in wet seasons is better than that in dry seasons. Total nitrogen(TN)and total phosphorus(TP)are the primary pollution factors in Weihe River, while conductivity is primary one in the Jinghe River and Beiluohe River. The biotic integrity of fish and benthic macroinvertebrate in wet seasons differs slightly from that in dry seasons, while the biotic integrity of periphytic algae in wet seasons has great differences from that in dry seasons. According to the main problems of river health in Weihe River Basin, the following countermeasures and suggestions are put forward. Excessive development and utilization of water conservancy projects should be controlled and water storage and release of dams should be regulated reasonably. Sewage disposal plants should be set up on both sides of the rivers to intercept and dispose the drainage. And water quality should be monitored termly, in which TN, TP and conductivity should be focused on. The oil development intensity in Weihe River Basin should be controlled to reinstate riverbank belt and slope habitat, guaranteeing the normal habitat and reproduction of aquatic organisms.