Simulating Uneven Urban Spatial Expansion under Various Land Protection Strategies: Case Study on Southern Jiangsu Urban Agglomeration

Pingxing Li,Hui Cao

doi:10.3390/ijgi8110521

Abstract

Urban spatial expansion (USE) is an uneven process affected by both natural and human factors, and land use regulation policy is of significance. To indicate the potential effects of different policies at a regional scale and then improving them under the context of increasing emphasis on land protection, we take Southern Jiangsu Urban Agglomeration (SJUA) in eastern China as a case study. Based on USE simulation with a minimum cumulative resistance (MCR) model under four scenarios related with arable and ecological land protection, we analyze the spatial differentiation of newly added urban construction lands and examine the changes of urban system with fractal analysis. Results indicate the allocations of newly added urban construction land differs by scenarios as well as total expanding amounts, and larger cities tend to grow faster. The share of the four largest cities (Suzhou, Nanjing(S), Wuxi, and Changzhou) were mostly higher than 40%. Accordingly, the final area of all cities was linearly corrected with their extant sizes in 2010. However, the differentiated allocations of newly added urban lands related to both increasing expanding amounts and different scenarios caused differences in the said linear relationships and also influenced urban rank-size in different degrees. It is concluded that the MCR model is feasible for simulating regional scale urban expansion and land protection strategies do not induce dramatic changes to the basic structures of regional urban system, but they are slightly different as land protection strategies change. The spatial distribution of protected lands affect the differentiation of both the predicted expanding amount of different cities and the regional urban systems significantly. It is of importance to optimize the spatial distribution of protected lands to regulate regional scale USE patterns and also urban systems properly.

Highlights

Urban spatial expansion (USE) is ongoing at an unprecedented speed in our world’s developing countries and regions [1]
Land Use Suitability (LUS) evaluation is proved to be effective and reasonable basically as most extant urban construction lands are distributed in zones with high suitability, while most ecological lands are in zones with low suitability
Most of the Southern Jiangsu Urban Agglomeration (SJUA) is within the Yangtze River plain, which lies at a low elevation and slope and is topographically suitable for land development

Summary

Introduction

Urban spatial expansion (USE) is ongoing at an unprecedented speed in our world’s developing countries and regions [1]. Urban construction lands are reported to increase by 58,000 km or 9% from 1970 to 2000 globally [2]. The share of developing countries and regions is increasing greatly, and China is a typical case with rapid urbanization where developed land increased from 13,148 km to 35,633 km during the period from 1990 to 2012 [3]. Urban agglomerations or megacities expand faster in both developed and developing countries [4]. As more issues are caused (and resolved) in regions composed by a group of cities, the uneven USE has received increasing research attention in recent years [10,11]

Results

Discussion

Conclusion