Search

For revealing the spatial distribution characteristics and laws of land use on topographic gradient under different geomorphic forms in poor mountainous areas, the paper took Bijie City as the research area, which was divided into karst and non-karst areas. Based on land use data and DEM in 2009 and 2018, different characteristics of the land use change under different terrain gradients was discussed through the methods of topographic index, topographic distribution index. The results are as follows. 1) The land use types in karst and non-karst areas are hierarchical in terrain gradient. Dry land, paddy field, garden land, construction land, road and water area have certain selectivity for low terrain, while woodland, shrub land, grassland and unused land have certain selectivity for high terrain, among which land use types in non-karst areas are more widely distributed in low terrain area. 2) It has obvious effect for the terrain gradient on land use diversity in karst and non-karst areas. It had great changes as the augment of terrain gradient in 2009. And in 2018, the lower the terrain gradient was, the higher the diversity was. Compared with non-karst area, the diversity of karst area is higher in interval 1, 2 and 5 than that of non-karst area, but the opposite is true in interval 3-4. 3) The terrain gradient effect of karst and non-karst land use degree is significant, which shows the higher the terrain gradient is, the lower the land use degree is. The spatial difference is influenced by natural environment, socio-economy and policy. [ABSTRACT FROM AUTHOR]