空间约束背景下海岸带湿地保护边界研究

摘要

The delineation of wetland reserve boundary is essential not only to the functional sustainability of wetland,but also to the coordination of land resource configuration and spatial distribution among wetland protection,farmland utilization and urban construction.This paper is conducted to analyze wetland reserve boundary in light of the theory of source and sink landscape interaction by using a case study of the southern bank of Hangzhou Bay.The spatial differentiation of wetland protect source and sink landscape including ecological bound and spatial constraints assessment were analyzed respectively.And wetland reserve boundary and its type were delineated by using the minimum cumulative resistance model.The case study demonstrated the applicability of research strategy by using minimum cumulative resistance model based on spatial constraints assessing and ecological bound zoning in delineating wetland reserve boundary.While accounting for 52.69％ is of the ecological bound,high constraint district or medium constraint district,only percent of 34.53％,12.79％ are low constraint district and none constraint district,showing an intensive constrained trend of spatial pattern.The area of wetland reserve boundary and buffer zone have the area of 49.1 1 km2,24.07km2 respectively,taking the percentage of 5.47％ in the southern bank of Hangzhou Bay,revealing that the space of wetland reserve is limited.In addition to ecological bound,wetland reserve boundary can be classified into three types including preserved forest area,farmland expansion and water SourceS.%湿地保护边界划定是维护湿地可持续发展的基础前提,也是协调湿地保护与农地利用、城镇发展土地配置与空间布局的必经途径.研究从湿地保护边界的“源-汇”生态景观互动视角着眼,明晰了湿地保护源及保护优先等级,建构了空间约束评价与生态断界来刻画汇景观空间层次分异,借助最小累积阻力模型测度与划分了湿地保护边界及其类型.研究发现:(1)基于多重因素的空间约束评价与湿地生态断界的划分,通过最小阻力模型有效地刻画外部因子集成对湿地保护的限制及差异,以量化方式描绘湿地保护所处阻力最小地带,为湿地保护边界划分提供了新的思路.(2)杭州湾南岸生态断界与中高约束的区域占据研究区52.69％比例,无约束地域仅为12.79％,奠定了综合因素空间约束强势的基本格局.加之低度约束区域占据34.53％,显示杭州湾南岸区域多介于高低空间约束性势转换或过渡阶段,压缩了湿地保护的空间.(3)研究划分湿地保护边界范围与缓冲区带为49.11、24.07km2,面积总和仅占据杭州湾南岸5.47％,湿地保护拓展和弹性调整空间极为有限.除生态断界提供湿地保护的天然边界外,湿地保护界限表现为保育林区、农地延伸型和水源保护型三类.