Multi-scenario analysis of land space based on PLUS and MSPA

Land space is an important link between human social-economic activities and the evolution of the natural environment. Its changes can directly reflect the transformation process of mankind's activities on the surface system, and it is a core element of the study of global environmental change. In the research, based on the "three districts and three lines" classification method of national land spatial, the urban space, agricultural space, and ecological space of Tianjin were divided. Natural trend, economic development, cultivated land protection, and ecological priority were set as four simulation scenarios, which were predicted by the Markov-Plus model for the spatial pattern of national land in 2030. Data statistics and the MSPA model were used to quantitatively analyze Tianjin's future land space from two aspects of structure and pattern. The main conclusions were as follows: (1) The overall accuracy of the simulation results of the Markov-Plus model was 0.971, and its kappa value was 0.948. The simulation accuracy was relatively high, which provides a reference for future spatial simulation prediction in this area. (2) In different simulation scenarios, the changing trend of Tianjin's land space scale from 2020 to 2030 was that urban space continues to increase, while agricultural space and ecological space decrease successively. (3) Each simulation scenario achieves good results for spatial prediction under the condition of setting limiting factors. In the natural trend scenario, the spatial variability of the types is more complex, the boundaries are more fragmented, and the spatial reference value of the territory is lower.