In this paper evolution of ancient lake in Taiyuan basin and changes of ecological environment were studied by optical enhancement of remote sensing image

geoscience analysis and historical records. Using 11 combinations we extracted information by means of the ratio method between MSS + 5 and MSS -7 gathered by landsat in Dec. 11

1973

May 9

1977 and Oct. 23

1979. Information about the contour of the ancient lake bank during different historical period was obtained

its acreage was measured by optical electronic scanner and analysed quantitatively. By analysing historical records we identified the date of the ancient lake

the influence of forest destruction on environment and shrinkage or extinction of the lake.