[Regulation framework of watershed landscape pattern for non-point source pollution control based on 'source-sink' theory: A case study in the watershed of Maluan Bay, Xiamen City, China].

Watershed landscape pattern regulation and optimization based on 'source-sink' theory for non-point source pollution control is a cost-effective measure and still in the exploratory stage. Taking whole watershed as the research object, on the basis of landscape ecology, related theories and existing research results, a regulation framework of watershed landscape pattern for non-point source pollution control was developed at two levels based on 'source-sink' theory in this study: 1) at watershed level: reasonable basic combination and spatial pattern of 'source-sink' landscape was analyzed, and then holistic regulation and optimization method of landscape pattern was constructed; 2) at landscape patch level: key 'source' landscape was taken as the focus of regulation and optimization. Firstly, four identification criteria of key 'source' landscape including landscape pollutant loading per unit area, landscape slope, long and narrow transfer 'source' landscape, pollutant loading per unit length of 'source' landscape along the riverbank were developed. Secondly, nine types of regulation and optimization methods for different key 'source' landscape in rural and urban areas were established, according to three regulation and optimization rules including 'sink' landscape inlay, banding 'sink' landscape supplement, pollutants capacity of original 'sink' landscape enhancement. Finally, the regulation framework was applied for the watershed of Maluan Bay in Xiamen City. Holistic regulation and optimization mode of watershed landscape pattern of Maluan Bay and key 'source' landscape regulation and optimization measures for the three zones were made, based on GIS technology, remote sensing images and DEM model.基于“源-汇”理论对景观格局进行调控与优化是一种较为经济、有效的流域非点源污染控制新方法,目前尚处在探索阶段.在景观生态学及相关理论与前人已有研究的基础上,以流域整体为对象,从2个层次构建基于“源-汇”理论的流域非点源污染控制景观格局调控框架: 1)流域层次:在分析流域“源-汇”景观合理的基本组合与空间布局方式的基础上,建立了流域景观格局整体调控与优化方法;2)景观斑块类型层次:将关键“源”景观作为重点调控与优化对象,建立了包含景观单位面积污染负荷、景观坡度、起传输作用的狭长“源”景观、临河“源”景观单位岸线长度污染负荷等4项关键“源”景观识别准则,并遵循镶嵌“汇”景观、局部增补带型“汇”景观、提高原有“汇”景观消纳污染物的能力等3项调控与优化原则,针对农村地区与城区不同的关键“源”景观类型,制定了9类调控与优化方法.最后将该框架应用到厦门市马銮湾流域,基于GIS平台及研究区遥感图像与数字高程模型,制定了马銮湾流域景观格局整体调控与优化模式及3个片区关键“源”景观调控与优化方案.