基于GIS的陕西省土地生态环境敏感性评价研究

依据陕西省土地生态环境目前存在的问题和生态环境敏感性理论,充分考虑生态环境敏感性的影响因素,选取了土壤侵蚀、土地沙化、地质灾害、生物多样性和生态环境等5个生态敏感性因子,并确定了其叠加值.通过资料收集、实地调研、遥感影像解译与分析、定量计算、专家评议总结等方法,得出陕西省土壤侵蚀类型与强度图、陕西省沙漠化类型与强度图、陕西省地质灾害图、陕西省生态环境遥感综合评价图、陕西省自然保护区与森林公园分布图等5个评价因子单要素专题图.利用ArcGIS软件对5幅单要素专题图按照其生态敏感优先度等级进行叠加分析,得到陕西省土地生态环境敏感性分区.发现极度敏感区占陕西省总面积的9.38%,主要分布在陕西北部的长城沿线地区,该区生态敏感性很高,抗干扰能力差,属重点生态保护区;重度敏感区占18.61%,分布在陕西长城沿线以南的榆林地区和秦岭的局部区域,该区生态敏感性较强,可以适度发展畜牧业;中度敏感区23.3%,分布在秦岭大部分区域及榆林和延安的交界地带,开发强度不宜过高;敏感区占33.03%,分布在渭北旱塬及延安南部、巴山的大部分区域和秦岭的部分区域,可以进行适度的土地开发;低敏感区占15.67%,主要分布在关中平原、汉水谷地等区域,这部分的土地是陕西土地利用的重要区域,适合高强度开发.

GIS-based assessment of sensitivity of land eco-environment in Shaanxi Province

In accordance with the ecological environment sensitive theory and the problems of land ecological environment existing in Shaanxi Province at present,fully considering the ecological environment sensitive influence factors,this paper has selected soil erosion,geological disaster,biodiversity and other 3 ecologic sensitive factors,and determined its superimposition value.Through the acquisition of information,real investigates and studies,quantitative evaluation and other methods,it obtains special charts of 5 appraisal factors.They are the type of soil erosion and the intensity chart,the type of desert and the intensity chart,the chart of geology disaster,ecological environment remote sensing synthesis evolution map,nature protection area and the forest park distribution map.The paper carries on the superimposition analysis using ArcGIS software to special charts of 5 single essential factors according to first rank of ecologic sensitive,obtains land ecological environment sensitive district of the Shaanxi Province.It has discovered that the extreme sensitive area accounts for 9.38% of the total area in Shaanxi Province,which lies mainly in north Shaanxi along the Great Wall.The specific weight sensitive area accounts for 18.61%,which is distributed in Yulin area south of the Great Wall and part of the Qinling region,the ecologic sensitivity is stronger in this area.The moderate sensitive area accounts for 23.3%,which is distributed in the majority of Qinling region and the border region between Yulin and Yan'an.The sensitive area accounts for 33.03%,which is distributed the Weibei and southern part of Yan'an,the majority of Mountain Ba and part of Qinling regions.The low sensitive area accounts for 15.67%,which is mainly distributed in the Guanzhong plain,the valley of the Han River and so on.