陕西省榆林地区生态环境评价研究

Appraisal of Ecological Environment in Yulin Area of Shaanxi Province

榆林地区地处典型的风沙草滩区和丘陵沟壑区的交错过渡地带,水蚀和风蚀都十分严重,区域生态环境极度脆弱多变。基于RS和GIS软件环境,采用榆林地区1980,1995和2000年3期Landsat TM4,3,2波段合成卫星影像数据为主信息源,在人机交互作业方式下进行信息提取,并结合区内各生态环境质量影响因子,建立了区域生态环境质量评价模型。经对研究区20 a来土地利用、土地覆盖变化和各类型区生态环境质量进行评价分析,认为榆林地区的生态环境虽有明显改善,但生态环境整体质量水平不高,恶化的趋势还没有得到控制。

Yulin area is situated in the transitional zone between the typical wind-sand-grassland area and the knoll-gully area, where both water erosion and wind erosion are extremely serious. The regional ecological environment is more and more brittle and changeable. For the judgment to the Yulin ecological environmental quality and the change, research was conducted to establish ecological environmental appraisal index systems of the transitional zone. The research was based on RS and GIS software and three issues of Landsat TM4, 3, 2 wave bands synthesized satellite data. Information source of Yulin area in 1980, 1995, and 2000 were used and information extraction was carried on under the man machine interactive work way. Combined with various influence factors of ecological environment quality, the ecological environment quality appraisal model for the area was established. By the study of 20 year land utilization and land cover change, as well as the appraisal analysis of various types of ecological environment quality, it is found that the Yulin ecological environment has been improved remarkably. However, on the whole, its ecological environment quality level is not high and the deteriorated tendency has not been under control.