Analyzing the Impacts of Urban Expansion on Green Fragmentation Using Constraint Gradient Analysis. Issue 4 (2nd October 2017)

• Record Type: Journal Article
• Authors: Jiao, Limin; Xu, Gang; Xiao, Fengtao; Liu, Yaolin; Zhang, Boen
• Is Part Of: Professional geographer. Volume 69:Issue 4(2017)
• Page Start: 553
• Page End: 566
• Publication Date: 2017-10-02
• Subjects: gradient analysis -- green space -- land fragmentation -- spatial constraint -- urban expansion; 梯度分析，绿地空间，土地碎裂，空间限制，城市扩张。; análisis de gradiente -- espacio verde -- fragmentación de la tierra -- control espacial -- expansión urbana; Geography -- Periodicals; 910
• DOI: 10.1080/00330124.2016.1266947
• Languages: English
• ISSNs: 0033-0124

Abstract

Abstract : Many existing gradient analysis methods are arbitrary or too simple in gradient partitioning and unsuitable for cities with irregular forms. We propose an improved gradient analysis method with urban structural features as spatial constraints to properly partition an urban area into more homogeneous buffers. Taking the Wuhan metropolitan area in China as an example, we use the improved gradient partitioning method and six landscape metrics to characterize urban expansion and green space fragmentation in 1989, 2001, and 2013 and investigate the relationship between urban green fragmentation and urban expansion using correlation analysis and regression modeling. The results show that the fragmentation of built-up area in each buffer generally decreases from 1989 to 2013, but the fragmentation of green space increases. For each time point, with growing distance from urban centers, the fragmentation of built-up area increases and green space fragmentation decreases. This shows that urbanization exerts a significant influence on fragmentation of urban green space from both a temporal and a spatial perspective. Intensive urban expansion moved outward mainly at the cost of agricultural land and resulted in more fragmented green space in the urban fringe. Further quantitative analyses show that the area ratio and fragmentation of the built-up area are statistically negatively correlated with the fragmentation of green space. The improved gradient analysis with spatial constraints can generate more homogeneous ring gradients and then lead to more reasonable results, thereby helping to better understand how urban expansion affects landscape dynamics.