Scenarios of changes in the spatial pattern of land use in China

Land use changes affect many aspects of Earth System functioning, for example in impacting global carbon cycle, contributing to climate change, or increasing soil erosion. The simulation of land use change is important in environmental impact assessment and land use planning. We assessed the land use scenarios of China in the next 100 years based on the SMLC (surface modelling of land cover change) model and Dyna-CLUE (dynamic conversion of land use and its effects) model. Three SRES scenarios were evaluated: Global Economy (A1FI): lean government, strong globalization; Continental Markets (A2a): lean government, regional culture and economic development; Regional communities (B2a): much government intervention, regional cultural and economic development. Ten land cover types were simulated, which are cultivated land, woodland, grassland, built-up land, water area, wetland, nival area, desert, bare rock and desertification land. The SMLC model was used to calculate changes in area for each land use types in the future at country level while the spatially explicit land use model Dyna-CLUE was used to simulate land use pattern at 2 km2 resolution based on the country level areas demands for each land cover type. The results show that the cultivated land would decrease in all of the three scenarios, while in the A2a scenario, the cultivated land would decrease with the lowest rate because of the high population growth, high level of market protection and low agricultural efficiency; in the B2a scenario, it would decrease with the highest rate caused by the decreased population numbers and increased crop productivity. The nival area would decrease with the highest rate in the A1FI scenario since the rapid introduce of new technology and the energy system is fossil intensive, which would discharge more greenhouse gas than other two scenarios. The area of natural ecosystems such as wood land, grassland, water area and wet land would increase significantly in the B2a scenario because this scenario puts more weight on environmental sustainability. The land use spatial pattern in China under the B2a scenario is simulated. The results are important to identify hotspots of land use change that need specific attention by the governments and the researchers.