基于水功能区的湖北省农业非点源污染控制区划

农业非点源污染已成为区域水质恶化的主要原因,有针对性地按照国家和地区对不同水功能区的水环境质量标准的要求划分农业非点源污染控制区,可以使非点源污染的控制更有效率.以湖北省103个县域为对象,以水功能区要求为基础,采用ArcGIS分析法确定县域水环境质量标准,在此基础上,采用水质污染指数法及内梅罗指数法解析各县域单元的污染类型及敏感性,最终划定研究区农业非点源污染控制分区.结果表明：1）湖北省可划分为Ⅱ类水质保护区的县域单元29个,划分为Ⅲ类水质保护区的县域单元74个;2）Ⅱ类水质保护区污染类型可划分为3类,主要为单一污染源污染,敏感区可划分为3类,分别为不敏感、轻度敏感及中度敏感;3）Ⅲ类水质保护区污染类型可划分为7类,主要污染类型为单一污染源污染和混合污染,敏感区可划分为3类,分别为轻度、中度及重度敏感;4）农业非点源污染控制区可划分为3个级别,包括2个一级控制分区,6个二级控制分区,23个三级控制分区.区划结果可为湖北省农业非点源污染管理和防治提供参考.

Control zone of agricultural non-point source pollution based on water function zone in Hubei Province

Agricultural non-point source pollution has become the major factor of water quality deterioration. By identifying agricultural non-point source pollution control zones according to the environmental quality standard requirements of different water function zones of the nation and provinces, the management efficiency for controlling non-point source pollution can be improved. Taking 103 counties of Hubei Province as basic units, based on the demand of water function zones, this paper identified the environmental quality standards for surface water at county level. On this basis, the agricultural non-point source pollution type and environmental sensitivity of each county were determined by using the method of water quality pollution index and Nemoro index. Finally, the pollution control zones were determined. The results show that, 1 ） 29 counties are divided into Class- 11 water quality protection area and 74 counties into Class-lU water quality protection area; 2） in Class-Ⅱ area, the pollution type is divided into three types, which are all single source pollution, and the environmentalsensitive area was divided into three regions, namely, non-sensitive, slightly sensitive and moderately sensitive regions; 3 ） in Class-HI area, there are seven pollution types and main pollution types are single source pollution and mixed pollution, and the environmentally sensitive area includes three regions, namely, slightly, moderately and seriously sensitive regions; 4） the pollution control zone is divided into three classes： the first class includes two regions, the second class includes six regions and the third class includes 23 regions. Our results can contribute to providing a basis for pollution management and prevention in Hubei Province.