【摘要】 基于土地利用数据,结合ArcGIS和Fragstats4.2计算研究区各类景观指数,分析广陵区2010—2015年景观生态风险空间格局与过程特征,为研究区生态风险管控措施的制定奠定坚实的基础.研究结果表明:(1)2010—2015年,广陵区景观格局发生了较明显的变化,草地、林地、耕地和水域面积降幅明显,建设用地扩张明显,扩张面积主要来自耕地和水域面积的转化. 2010—2015年,广陵区景观破碎度整体呈降低趋势,分离度也明显的降低,分维数整体变化不大,耕地的分维数最高,最小的是其他土地.(2)景观生态风险等级有逐渐降低的趋势,中度风险区面积明显减少,而轻度风险区面积有所增加,高度风险区面积减少也比较明显.(3)从空间分布上分析,整体上广陵区的风险类型从西部向东部风险等级有增加的趋势.较高风险区主要分布在施桥镇、沙头镇和头桥镇等农村地带,该区域主要的景观类型是耕地,极易受到人为活动的干扰;轻度风险区主要分布在西北部的汤汪乡和杭集镇周边的农村地区;微度风险区大部分在广陵区市辖区,主要的景观类型是建设用地,抗干扰能力强,风险值最低.基于不同土地利用变化的生态风险评价,对建立研究区生态风险预警机制、降低生态环境风险、维护区域生态系统服务功能具有十分重要的意义.更多还原

【Abstract】 Based on land use data,combined with ArcGIS and Fragstats4.2 to calculate various landscape indices,the spatial pattern and process characteristics of landscape ecological risk in Guangling District from 2010 to 2015 are analyzed,which lay a solid foundation for the formulation of ecological risk management and control measures.The results show that:(1)From 2010 to 2015,the landscape pattern of Guangling District has changed significantly. The area of grassland,woodland,cultivated land and water has decreased significantly,and the expansion of construction land is obvious. The expansion area mainly comes from the transformation of cultivated land and water area. From 2010 to 2015,landscape fragmentation in Guangling District showed a decreasing trend as a whole. During this period,the degree of separation of the study area also decreased significantly,and the fractal dimension changed little as a whole. The fractal dimension of cultivated land was the highest and that of other land was the smallest.(2)Landscape ecological risk level tends to decrease gradually,the area of moderate risk area has decreased significantly,while the area of mild risk area has increased,and the area of high risk area has decreased significantly.(3)From the spatial distribution analysis,the overall risk type distribution in Guangling District tends to increase from the west to the east. The types of higher risk areas are mainly distributed in rural areas such as Shiqiao Town,Shatou Town and Touqiao Town. The main landscape types in this area are cultivated land,which is easily disturbed by human activities. The types of mild risk areas are mainly distributed in the rural areas around Tangwang Township and Hangji Town in the northwest. The types of slight risk levels are mostly in Guangling District,and the main landscape type is construction land. It has strong anti-interference ability and lowest risk value.Based on the ecological risk assessment of different land use changes,it is of great significance to establish the ecological risk early warning mechanism,reduce the ecological risk and maintain the regional ecosystem service function.更多还原