Basin Water Sensitivity and Its Impact on Spatial Expansion: A Case Study of the Taihu Basin, China

Water is the most important and sensitive factor controlling urban development in basins. This paper developed a novel approach to construct a Basin Water Sensitivity Index (BWSI) from the perspective of integrated basin management. The correlation between the spatial expansion of development and water sensitivity over the past 30 years in the Taihu Basin was analyzed using BWSI and urban development data. The analysis found that, (1) from 1985 to 1995 the spatial expansion of developed areas in the Taihu Basin was unrelated to BWSI; (2) from 1995 to 2007 the expansion intensity decreased with an increase in BWSI; and (3) from 2007 to 2017 there was a significant increase in the spatial development expansion intensity and the area of expansion was concentrated in low BWSI areas, while the constraints of water sensitivity on spatial expansion were more obvious than in previous years. The analysis illustrated how BWSI affected spatial growth in a basin and this research can be used to help formulate a spatial growth management policy that includes water sensitivity and provides a scientific basis for coordinating the relationship between economic and social development with water resources and the environment.