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Hexi Aisle located in west of Gansu province is the base of national trade-corn. Recent years, because of the increase of population, the improving of economy and the damage of environment, many ecological problems appear more serious, such as desertification, shortage of water and degeneration of vegetation. So, in order to protect and improve the ecosystem and avoid advanced damage, it’s necessary to analyze the change of the eco-environment during the past ten years.
Remote sensing is good at observation on long-term and insignificant change in environment. In the paper we used two periods TM image combined band 2,3,4. Then, through manual explaining under the GIS software, we got the environment vector data and built graphics database and attribute database. Those data primely present the eco-environment change of the past 10 years. With GIS method, overlay the two periods eco-environment vector map to taking the detail of the dynamic data of the eco-environment change (Guan Weihe, 1992).
Regional eco-environment change is important part of the globe change analyze, many research indicate that regional eco-environment is driven by the natural and human activities. In our research, we find that many eco-environment changes are influenced by the alteration of the climate and human activities. Integrating social, economic and climate factors, we think that natural factors including temperature, water, salt, eroding and human activities including unreasonable agricultural practices, heavy livestock grazing and firewood cutting is the dominant driving factors in the change of the eco-environment. Especially, in the change and distribution of the eco-environment, human activities make a more important role. In addition, during the past 14 years, three major drainage area are suffering notable eco-environment including degeneration of vegetation, river water shortage, river breaking and lake shrinking. Accompanying the increase of population, excessive digging, heavy livestock grazing, strong eroding and desertification became more and more serious and rapid.
Because of the weak eco-environment and special geographic location, research region is more important area to the regional and globe change analyze. The analyze in the region is very significant to the monitor of the eco-environment change, improving the weak eco-environment and avoiding natural disaster, especially reducing desertification and avoiding dust storm.
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