With strengthening control of point source pollution , agricultural non - point source pollution will be the main pollution source to the three - gorge reservoir area 随着点源污染的有效治理,农业面源污染将成为三峡库区水体的最主要污染源。
With the rapid urbanization , while point source pollution is of control , urban non - point source pollution turns into a serious threat to urban watershed 摘要随着城市化迅速发展,点污染源基本得到控制,非点污染源对城市水体构成严重的威胁。
Rainfall - runoff simulation is the very important technique for soil erosion , non - point source pollution , surface water balance calculation and some other study fields 降雨径流模拟是土壤侵蚀、非点源污染、地表水量平衡计算等众多研究领域的非常重要的技术手段。
So it is important to control and manage agricultural non - point source pollution to guarantee the water quality and realize the agricultural sustainable development 因此,要实现农业可持续发展,保证三峡水库水体质量,对农业面源污染进行控制和治理变得非常重要。
It is reported that agricultural non - point source pollution influence 30 % ~ 50 % of the world land and 12 % of 2 . 1 billion hm2 land in the world is caused by agricultural non - point source pollution 据报道,农业面源污染影响了全世界陆地面积的30 50 ,并且在全世界不同程度退化的21亿hm ~ 2耕地中,约12由农业面源污染引起。
The study on absorption of pesticides will be tested in future . these may offer guide and reference to establish riparian buffer controlling agricultural non - point source in shanghai and other plain districts 根据试验研究,以及结合国内外的先进经验,提出了适合上海市情的缓冲带设计和管理模式,并对缓冲带进行了环境效益评估。
( 2 ) according to the requirement of the item , the non - point source pollution metadata standard that is accorded with fgdc standard has been organized and non - point source pollution metadata has been built based on metadata standard ( 4 )利用gis技术结合面源污染危险性评价模型modifiedusle对三峡库区农业面源污染的危险性进行了评价。
Now the study of the agricultural non - point source pollution is mainly to integrate gis with environmental model . building spatial database is the basement of using gis to study non - point source pollution 目前对农业面源污染的研究主要是将gis作为非常有用的工具结合到环境模型中,而建立空间数据库是利用gis进行面源污染研究的基础。
Water quality is an important issue for flood management study , in the thesis the estimation of non - point source pollution load and simulation are researched in consideration of water quality monitoring situation 洪水管理中的重要问题在于需要研究水质,论文结合目前我国水质监测现状,比较深入地研究了非点源污染模拟与负荷估计问题。
The results of this dissertation include : ( l ) this study has designed and built an agricultural non - point source pollution spatial database of the three - gorge reservoir area in chongqing based on geodatabase and case tools 在论文进行过程中取得了以下一系列成果: ( 1 )基于geodatabase数据模型,利用case工具设计并建立了三峡库区农业面源污染空间数据库。