Spatial and temporal evolution of urban reserve available land resources in the Karst region of North China from 1990 to 2020: a case study of Jinan city

With the rapid development of urbanization, land resources are mainly converted into urban areas in most karst mountain regions of North China over the last decade, so studying available land resources would have implicational significance to regional planning and sustainability. Based on RS, GIS, DEM, slope information and the evaluation methods for reserve available land resource, this study explored the spatial and temporal evolution of urban reserve available land resources from 1990 to 2020 in Jinan city, which is located in the karst region of North China. The results reveal that the potential of the reserve available cultivated land in Jinan city is large, covering an area of 360.67 km2, and the differences of reserve available cultivated land for each district are mainly caused by the combined effects of regional conditions, economic conditions, population, and industrial zones. The area of reserve suitable construction land in Jinan city is 292.48 km2, which is decreasing and mostly in the southern part of the study area. Based on the overlap and differences of the two types of land, combined with regional socio-economic development and natural environmental conditions, the reserve land resources in the southern region of Tian Qiao, Chang Qing and North Huai Yin, Shi Zhong, and Li Xia within the study area can be converted into construction land, but the reserve land resources in the central and southern regions of Li Cheng and the central and southeastern regions of Chang Qing can be converted into new cultivated land.