Land use and spatiotemporal pattern evolution of a mountain city agglomeration: A case study of the urban agglomeration in Dianzhong (central Yunnan), southwestern China

Land use is attracting increasing amounts of attention in today's society. Taking the central Yunnan city cluster as an example, in this study, a quantitative method was used to study the evolution of land use and its spatial-temporal patterns. The results show that (1) in general, from 2000 to 2018, the area of construction land increased significantly, while the area of cultivated land and grassland decreased dramatically, and the area of woodland decreased slightly. In recent years, the water area increased, but the growth rate was slow and unstable, exhibiting a spiral growth trend. (2) From the perspective of land-use change, the overall rate of the land-use change in the study area was variable. For example, the rate of change of construction land was relatively fast compared with those of other land-use types. The rates of change of the forest area and water area were relatively slow. The drastic spatial changes in land use were mainly concentrated in the cultivated land, grassland, and construction land. The four types of land use experienced significant mutual transformations, among them, grassland, cultivated land, woodland, and construction land experienced the most significant transformations. (3) From the perspective of the evolution of the spatiotemporal pattern, the rate of change of the spatial patterns of all of the land-use types in the central Yunnan urban agglomeration increased, and the areas with drastic spatial changes were mainly concentrated in the grassland, arable land, and woodland. The construction land expanded in the northeast and southeast directions, which was related to the urbanization process and the regional economic development center of the central Yunnan urban agglomeration.