By taking 2007 TM images and 1∶250 000 contour maps of Bazhong City as data sources and using GIS spatial analysis functions,landuse database of Bazhong City is established and the DEM,slope,and terrain niche index chart are produced.Then,slope gradient,elevation gradient,and terrain gradient are respectively overlaid with landuse landscape data.The distribution characteristics of different landuse landscapes at different terrain gradients are discussed by introducing the dimensionless distribution index.Re...