[Spatial correlation between non-agricultural land expansion and soil quality in Suzhou City]

Based on the layer of non-agricultural land expansion interpreted from 4 Landsat TM images in 1984, 1995, 2000 and 2003 and the soil quality map, the patterns of non-agricultural land expansion occurring on soil quality levels in Suzhou City were analyzed. It was indicated that the non-agricultural land expansion happened mainly on the soils with high quality during 1984-2003. 90% of the expansion took place on the soils with moderately high quality (grade 2), and the next was those with high quality (grade 1). In the meanwhile, the expansion on the soils with moderate (grade 3) and low quality (grade 4) was only less than 1% of total area. From the viewpoint of soil quality, we should ponder more over the opinion on "dynamic balance of total amount of arable land between occupying and supplementing".