县域景观生态风险评价

Landscape ecological risk assessment of county

【目的】利用地理国情数据,定量化研究县域尺度下景观生态风险的变化趋势。【方法】以2015和2017年安徽省宿松县国情数据分类合并后的景观分布图为数据源,在地理信息系统(GIS)技术和Fragstats 4.2软件支持下,基于景观指数,采用地统计学方法,定量化分析2015-2017年宿松县土地景观动态变化、生态风险的时空变化及人类干扰活动对其的影响。【结果】宿松县景观破碎化程度不断增高,多样化程度不断增强,景观分布呈复杂趋势;西北部景观破碎度、分离度、分维度均较低,景观多样化水平低,景观生态风险较低,中部和东南部景观破碎度、分离度、分维度较高,景观分布结构较为复杂,景观生态风险较高;宿松县低生态风险区、较低生态风险区、中等生态风险区面积呈降低趋势,而较高生态风险区和高生态风险区面积呈增加趋势。【结论】宿松县景观生态风险程度有所增加,生态等级表现为低等级向相邻的高等级转化,潜在生态风险程度从高到低排序为矿产资源区、鱼米之乡、交通枢纽镇、农业区、山地旅游区。

[Objective] The geographic national conditions data was used to quantitatively study the change trend of landscape ecological risk at the county scale. [Method] Based on the geographic and national conditions data supported by the GIS technology and Fragstats 4.2 software, the landscape index were selected and the geo-statistical methods were used to analyzed the dynamic changes of landscape, spatial-temporal changes of landscape ecological risks and human disturbance activities in Susong County from 2015 to 2017.[Result] In the northwest, landscape fragmentation, landscape separation, landscape fractional dimension, the level of landscape diversity and landscape ecological risks were all lower;In the central and southeast,landscape fragmentation, landscape separation, and landscape sub-dimension were higher which shows that the landscape distribution structure was more complicated, and the landscape ecological risk was higher;The low ecological risk areas, lower ecological risk areas, and medium ecological risk areas were decreasing, while the areas of higher ecological risk areas and high ecological risk areas were increasing. [Conclusion] From 2015 to 2017, the degree of landscape ecological risk in Susong County increased, and the ecological risk level wastransformed from a lower level to an adjacent higher level. The ecological risk levels of mineral resource areas,fish and rice towns, transportation hub towns, agricultural areas, and mountain tourist areas were arranged in order from high to low.