定西半干旱地区生态环境的遥感动态监测分析

对定西地区的定西县、渭源县、陇西县和通渭县的生态环境进行监测。以 1990年和 2 0 0 0年 2期TM数字图像为主要信息源 ,进行屏幕目视解译 ,取得了初步的本底数据。建筑交通及矿区用地增长率为14 .97% ;农业用地增长率为 8.0 2 % ;林地增长率为 11.2 3% ;其它如河滩地、宜林草荒地则相应有所减少。定西地区经过 10 a的发展 ,土地利用和土地覆盖日趋合理 ,但还存在诸如土地利用率不高 ,农业用地比重过大 ,畜牧业用地比重太小 ,以及造林面积大 ,而存林面积小 ,树木成活率低 ,退耕还林还草力度不够等问题。通过对监测结果的分析 ,说明了遥感技术在定西这一特殊地区土地利用 /植被覆盖动态监测中已被有效地应用 ,同时有针对性的提出一些合理化建议 ,以期有利于项目区土地利用和植被覆盖的合理化

Remote Sensing Dynamic Monitor Analysis on Ecological Environment of Dingxi Semi-arid Region

The two periods of Landsat TM/ETM images in 1990 and 2000 are used to dynamically monitor the ecological environment of Dingxi, Weiyuan, Longxi, and Tongwei counties. The background data are obtained through screen visual interpretation. The construction, traffic, and mining land increase by 14.97%. The farming land increases by 8.02%. The woodland increases by 11.23%. The bare land, which is suitable for forest and grassland, and floodplain land decrease correspondingly. In the later 10 years, some measurements are carried into execution, for example, small basin integration control, transferring from cultivated land to forestland and grassland, the balance between grass and animal, and rotation grazing and closing of vegetation, which are results of the rationalization of land use and land cover. But there still consists of some problems such as low land use rate, higher ratio of agriculture land, low ratio of stockbreeding land, low ratio of the trees surviving.