论文部分内容阅读
湖南省保靖县设计以引水方式开发白岩洞地下河为城镇生活供水水源。该地下河的补给有大气降水和地表水 ,几个主要地表水入口多为岩溶洼地 ,洼地中分布着农田和人口密集的村庄 ,地下河系统森林覆盖率较低。地下河出现一些环境问题 ,如地下河水中出现农药和化肥的残留成分、泥沙含量在雨季剧增、地下河水细菌总数和大肠杆菌群超过国家饮用水标准规定的量等。同时 ,开发地下河也会对引水工程沿线地区的自然、社会和生态环境造成有益的和不利的影响 ,如挖掘隧洞可增加引水工程水量、高位自流供水可降低成本 ,白岩洞地下河淤积、部分村庄缺水、生态不良反映等。应抓住开发白岩洞地下河的机遇重新整理地下河流域土地资源 ,调整用地结构 ,增加林业用地面积和投资 ,建立水源卫生防护带 ,控制农药化肥用量和类型。
Baojing County, Hunan Province, designed to develop water diversion Baiyan underground river water supply for urban life. The underground river is replenished with atmospheric precipitation and surface water. Most of the major surface water inlets are karst depressions. There are farmland and densely populated villages in the depressions, and the underground forest system has a low forest coverage. There are some environmental problems in the underground river, such as pesticides and fertilizers in the underground river, residual sediment content in the rainy season, the total number of underground river bacteria and coliform bacteria than the amount of national drinking water standards and so on. At the same time, the development of underground rivers will also have beneficial and unfavorable impacts on the natural, social and ecological environment along the water diversion project. For example, excavation of tunnels may increase the water diversion project, high gravity gravity supply will reduce costs, silt in Baiyan underground river and some Village water shortages, poor ecological response. We should seize the opportunity of developing the underground river in Baiyan Cave to rearrange the land resources in the underground river basin, adjust the land use structure, increase the area and investment of forestry land use, establish the water source health protective belt, and control the dosage and types of pesticide and fertilizer.