The output of PCA was generated by SPSS. The research shown that the changes of pattern are notable. The landscape patches such as cropland, residential site and saline land increase rapidly in contrary to reduction of grassland, forestland, water area and wetland to different degree.
in 1990 and 1999,grassland,agricultural land,and saline land became the main land use/cover type in the basin. The total tendency of land use/cover change in the study area from 1973 to 1999 is that: the area of agricultural land,residental land,and grassland was increased even more;