Implications of land use policy on impervious surface cover change in Cixi County, Zhejiang Province, China

Abstract

There is a growing need to understand interactions between land use policies and the development of impervious surfaces. This paper (1) develops an approach to quantify impervious surface change in urban areas using multi-temporal remotely-sensed data sets; and (2) links observed change to change in land use policies. Cixi County in Zhejiang Province, China was used as a representative case study. Landsat imagery from 1987, 1995, 2002, and 2009 was used to detect impervious surface change. First, impervious surfaces for each image were estimated at the sub-pixel level via multiple endmember spectral mixture analysis (MESMA). Second, a high pass change filter (HPCF) was proposed to identify impervious surface change over time. Third, the Getis–Ord (Gi∗) metric was applied to the HPCF results to determine areas of substantial change (hot spots). In terms of the first objective, results suggested that the HPCF-Gi∗ metric could successfully reveal the location, intensity, and geographic extent of significant change in impervious surface coverage. With respect to the second objective, two major mechanisms of impervious surface change were identified: new land development and redevelopment of existing impervious surfaces. The nature and spatial pattern of these mechanisms can be explained through two classical urban growth models. We found that since 1994 the annual rate of impervious surface growth decreased considerably, suggesting that national land protection policies implemented in that year may have had some effect. However, the total area of impervious surface cover continued to increase, particularly in and around urban areas due to the above mechanisms. Both new land development and redevelopment could be linked to land use regulations and their implementation at the local level through local economic development pressure, the construction of transportation corridors, and the incentive structure for local government.