区域生态风险评价——以呼和浩特市区为例

区域生态风险具有大尺度、多因素、多风险受体的特点,难以直接定量;从生态风险的定义出发,构建景观破碎度和面积加权生态价值指数评价区域生态风险,并以ArcGIS和Fragstats软件为研究平台,通过空间采样和插值方法得到区域生态风险的空间分布规律。以2006年Spot卫星遥感数据解译的呼和浩特市区土地利用图为例,研究结果表明生态风险值范围在0.04-0.26之间,空间梯度差异明显,风险较高区域为东北部的大青山山区以及西南角的平原农业区,北部风险驱动力主要来自土壤侵蚀、地下水源地水位下降、水质恶化以及林地的退化;南部则是快速工业化导致林地、草地、特别是耕地景观转换为居民与工矿用地景观。案例研究结果表明所建方法直观、简便,可定量描述区域景观生态风险的相对大小和空间分布规律。

The regional ecological risk assessment of Hohhot City

The regional ecological risk has the characters of large scale, multiple stressors and multiple types of agents and difficult being quantified, From the definition of ecological risk, the ecological risk assessment method based on the indexes of landscape fragmentation degree and land value coefficient weighted by areas proportion has been put forward in this paper. Based on software platforms of ArcGIS and FRAGSTATS, the isoline map for ecological risk can be created by using the spatial sample method and the ordinary Kriging interpolator method. The land use map of Hohhot City for year 2005 was selected as example,the scope of ecological risk are between 0.04-0.26,but spatial difference of them are obviously, which high risk region locate at northeast mountainous area and southwest corner of faming land,. The driving force of north areas comes from soil erode, underwater and forest degradation, while that of south areas are the rapid industrialization,which make the forest, grass and especially agriculture land rapidly convert to industry use land. The results show the method set up in this paper is intuitionistic and convenient. It can be used to score relatively value and rules of spatial distribution for regional ecological risk.