Model-based analysis of future land-use development in China

The recognition that land-use changes are directly linked with economic decisions has led the land use change (LUC) project at the International Institute for Applied Systems Analysis (IIASA) to adopt an economic framework as the organizing principle of its modeling efforts. This paper discusses three complementary approaches used for analyzing and projecting regional land use in China. First, an enhanced agro-ecological zones (AEZ) assessment model provides a spatially explicit measure of production potentials for agricultural land uses. Next, land-use change scenarios are assessed with an extended input-output model of China's economy. Finally, we indicate how land-use policy alternatives can adequately be analyzed in a multi-region economic framework using optimization when an AEZ-based representation of climate and biophysical conditions is incorporated in the model specification. The analysis makes a strong appeal for sustaining efforts that can furnish rapid technological progress in land-based sectors, and it suggests that an increase of grain imports to about 10-15% of China's current total grain output would greatly reduce the pressure on cropland and water resources, especially in the northern half of the country