中国北方农牧交错带生态环境的空间格局演变

中国北方农牧交错带受自然条件和人为活动等多种因素的综合影响,生态环境问题比较突出,成为生态环境研究的典型区和理想地带。论文以此作为研究对象,选择能反映生态环境特点的多种空间数据信息,利用数字网格模型,通过采用空间叠加的分析方法,评估北方农牧交错带1989年和1999年的生态环境背景状况,并对北方农牧交错带生态环境变化及空间格局特征进行研究。结果表明:①1989至1999年,北方农牧交错带生态环境背景状况从东南向西北逐渐变差;②1989至1999年来,北方农牧交错带生态环境背景状况逐渐变差;③北方农牧交错带生态环境背景状况变化严重地区集中在晋陕蒙宁甘交界处、科尔沁沙地区、青海海东地区3个区域;④在205个旗县中,宁夏盐池县、内蒙古翁牛特旗、陕西定边县、甘肃环县、青海尖扎县、山西汾西县等12个旗县的生态环境变化最为严重,60%以上的面积生态环境背景状况逐渐变差。

Change and Spatial Pattern of Eco-environment in the Farming-pastoral Ecotone of the Northern China

The farming-pastoral ecotone of the northern China is a typical and ideal zone for stu-dying eco-environment.The eco-environment is vulnerable in this area,which is attributed to the natural conditions and human activities.First,the study builds the diagnostic indicators of eco-en-vironment background condition,based on multi-subject spatial data to reflect the characters of the eco-environment.Then,the eco-environment is evaluated in 1989 and 1999 by using the digital grid model and the spatial analytical method.Next,the changes and spatial pattern of the eco-environment are analyzed.The results are as follows (1)The eco-environment background condition becomes worse from southeast to northwest in the farming-pastoral ecotone of the northern China.(2)The eco-environment background condition deteriorates from 1989 to 1999.(3)The contiguous areas of Shanxi-Shaanxi-Inner Mongolia-Ningxia-Gansu,Horqin sandy land and its outer area and the eastern Qinghai province witness the serious eco-environmental changes.(4)The eco-environment background condition of 12 counties is the worst in the 205 counties of the farming-pastoral ecotone of the northern China,they are Yanchi county of Ningxia,Wengniute banner of Inner Mongolia,Dingbian county of Shaanxi,Huanxian of Ganshu,Jianzha county of Qinghai,Fenxi county of Shanxi and so on,the affected area of every county is more than 60%.