Land use change and environmental stress of wheat, rice and corn production in China

Grain self-sufficiency is one of the most important agricultural policy goals in China. With only modest imports, China has succeeded in feeding 22% of the world's population on only 7% of its land. However, a high price has been paid for this enormous achievement. Increase in grain yields, in particular in rice, as the main source of production growth, relied heavily on intensive use of physical inputs and increasing intensity of farming systems. Soil degradation, water scarcity, and severe pollution were among the consequences as well as declining efficiency of fertilizer application. Using county-level panel data from 1980 to 2003 and graphical (GIS-based) analysis, this paper first looks at the spatial change of the major grain production across regions over the past two decades, towards the northern and northeastern provinces. The analysis is complemented by using a random panel data model, which underscores the significant influence of land availability, degree of urbanization, and government policy on grain production. Finally, this analysis addresses environmental stress which includes both soil degradation and water shortage. The latter is already severe in many of the traditional grain producing areas, but will now become a bigger problem in the “new” grain producing areas, as these have traditionally much less water resources. Hence, while the economic rational of the “grain shift” towards the northern and northeastern regions is understandable, its sustainability is not guaranteed.

Research Highlights► The grain yield increase in China relied on intensive use of physical inputs. ► The increase in grain productivity leads to much environmental degradation. ► Grain production shifted from the central and south to the north and northeast. ► Land availability, degree of urbanization and R&D policy are the main factors.