Quota Restrictions on Land Use for Decelerating Urban Sprawl of Mega City: A Case Study of Shanghai, China
The mega cities of China are faced with great pressure from conflict between huge land demand for construction use and limited resources. To improve this situation, it is necessary to slow the increasing rate of built up land and even reduce the existing built up land by improving land use efficiency. Herein, land use planning with urban sprawl deceleration is proposed. Land quotas are important tools for the control of land use planning in China, but the current quotas are mainly in the form of increment, thus cannot support land use planning with urban sprawl deceleration. To address these issues, we developed a model named "current plan requirement response (CPRR)" to optimize the land quotas. With this model, we investigated the current status of land use, the process of land use planning, and the requirements of land use planning with urban sprawl deceleration in Shanghai. It was found that the current land quotas have provided somewhat inhabited conversion of arable land to built up land, but scarcely any regulation of land use efficiency or protection of natural environment. Then, the land quotas were optimized and quota management recommendations were made. The optimized land quotas included four aspects of quotas: arable land protection, ecological conservation, scale constraint on built up land and economical and intensive land use. These new land quotas could be used to guide reduction of built up land and increase ecological land in China's mega cities. It might also be beneficial for easing conflict between supply and demand of built up land, for building an eco friendly city land use structure.