Spatio-temporal processes and causes analysis of Jiayuguan oasis in China over a 23a period

摘要

Environmental change of oases in the arid regions of China is a subject of recent concern. Although many changes have been recorded qualitatively through the use of photography and historical reports, little quantitative information has been available on regional scale. Basing on RS images which all were rectified, interpreted and classified with ArcGIS or Erdas softwares, this paper studied the spatio-temporal processes and causes of Jiayuguan oasis over a 23a period. It also evaluated the condition of Jiayuguan oasis in relate to human being and natural distributions. The result shows that, during the years between 1986 and 2009, oasis area increased from 109.93 to 189.68km², total area of oasification land has an increase tendency. Factors influencing oasification occurrence is human being activities including urban economic development, fixed assets investment, transportation construction, state and local policy changes and urban population growth. Other factors also affected it but can be ignored duing to the short scale of study time.