Modelling the future variations of Land Use and land cover in the middle reaches of Heihe River, northwestern China

CLUE-S (the Conversion of Land Use and its Effects at Small Region Extent) Model was used to predict land use and land cover change (LUCC) from 2001 to 2020 in Zhangye City. The modeling built 3 kinds of water amount restriction scenarios. The base map was the land use map from TM image of 2001. 10 kinds of important driving factors of LUCC were chosen by Arcview 3.3. The weighting coefficient of each land was analyzed with SPSS13.0. The modeling results were: 1) farmland decreases in three scenarios, which is negatively correlated with available water amount; 2) woodland and grassland increase in three scenarios, which positively relates to available water amount; 3) the change of water area is not obvious in three scenarios; 4) the urban area does not change in scenario 1, but increases in scenario2 and 3; 5) the wasteland greatly decreased.