基于景观格局演变的流域生态风险评价与管控——以贵州赤水河流域为例

以岩溶地区典型流域——赤水河流域为研究对象,以2000、2005、2008、2013年4期遥感数据为基础,结合Arc Map的空间分析功能,对流域景观格局演变过程进行分析,构建流域生态风险评价体系与管控措施。研究表明:2000~2013年赤水河流域无风险区、潜在风险区、轻度风险区分别由1.66、2.95、75.41 km~2上升至5.63、21.81、115.45 km~2,而中度、重度风险区却分别下降了35.6和40.27 km~2;历年生态风险演变格局为以城乡建设用地为中心,生态风险由轻度、中度、重度向潜在或无风险区过渡,轻度、中度、重度主要以点状扩散或增加,潜在及无风险区则连片分布于农田区和山地丘陵区;基于不同生态风险区的风险源管控对策,对建立流域生态风险预警机制、降低流域生态环境风险、维护流域生态服务功能具有十分重要的意义。

ECOLOGICAL RISK ASSESSMENT AND MANAGEMENT OF WATERSHED BASED ON LANDSCAPE PATTERN CHANGE——A CASE STUDY OF THE CHISHUI RIVER BASIN IN GUIZHOU

The Chishui River Basin as a typical karst area was selected as the research object,based on remote sensing data of 2000,2005,2008,and 2013 along with ArcMap spatial analysis function of watershed landscape pattern process analysis,construction of watershed ecological risk assessment system and control measures.The results showed that:during 2000-2013,the risk-free zone,potential-risk zone,and low-risk region increased from 1.66 km2,2.95 km2,and 75.41 km2,respectively to 5.63 km2,21.81 km2,and 115.45 km2,and the moderate-and serious-risk areas were decreased by 35.6 km2 and 40.27 km2,respectively.The ecological risk evolution pattern for the urban and rural construction land as the center,the ecological risk evolving from mild,moderate and severe to potential or no risk zone,mild moderate and severe mainly from point spread or increase potential and no risk areas are distributed in the contiguous farmland area and mountainous hilly region;source of risk control measures of different ecological based on the risk area,has very important significance to establish the early warning mechanism,ecological risk reduction basin watershed ecological environment risk,maintain basin ecological service function.