Review on the Simulation of Non-Point Source Pollution in the Hilly Region of Southern China
GAO Huiran;SHEN Lin;LIU Junzhi;ZHU Axing;QIN Chengzhi;ZHU Liangjun;State Key Lab of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences;University of Chinese Academy of Sciences, CAS;Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University;State Key Laboratory Cultivation Base of Geographical Environment Evolution (Jiangsu Province);Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application;Department of Geography, University of Wisconsin-Madison;
With the increase of economic development, water quality degradation caused by non-point source pollution has become a serious problem in the hilly region of southern China. It is hard to set up controllable experimental environment at the watershed scale due to the complexity of non-point source pollution processes.Model simulation has become an effective way to facilitate watershed management and planning. Related studies on the simulation of non-point source pollution have been conducted in this region. However, few works have been done to summarize the outcomes of shortcomings of these studies and to point out the future research directions. Firstly, this paper analyzed the physical mechanism of non-point source pollution and regional characteristics such as special land features, human activities in this region and pointed out that the simulation methods of non-point source pollution in this region should meet the following demands:(1) coupling multiple watershed processes such as hydrology, soil erosion, plant growth and the migrating and transforming of nonpoint source pollutants;(2) spatially fully distributed in order to express the spatial heterogeneity of non-point source pollutant loading, and describe the migration and transformation routes of pollutants explicitly in this region;(3) taking the special land features and human activities into consideration which have important effects on the process of non-point source pollution. Then, based on the above demands, this paper summarized the current studies on the aspects of migration routes modeling and the representation of special land features and human activities in this region, and analyzed the problems of existing methods for non-point source pollution modeling that applied in the hilly region of southern China. On the aspect of spatial discretization, currentmethods cannot accurately describe the spatial heterogeneity of non-point source pollution processes, and the modeling of pollutant transport routes is limited to semi-distributed approaches which can't describe the exchange relationship of material and energy among adjacent spatial units at the hillslope scale. On the aspect of describing the regional characteristics, some watershed processes that are special in this region are absent in the current models. At last, future research directions were discussed on the following aspects:(1) Strengthen the description of the special landscape features, and explore the method of spatial discretization that suitable for hilly region of southern China;(2) Improve the construction of the fully-distributed migration routes of nonpoint source pollutants;(3) Conduct comprehensive representation of special land features and human activities in the fully-distributed non-point source pollution model. This paper aims to provide references to the simulation of non-point source pollution in the hilly region of southern China, which can then serve as an effective tool for scientific watershed management.
【Fund】： 国家自然科学基金项目(41601413、41431177、41401205);; 江苏省自然科学基金项目(BK20150975、BK20140921)
【CateGory Index】： X52
【CateGory Index】： X52