Ecological consequences of rapid urban expansion: Shanghai, China

and expansion since the late 1970s, accompanied by rapid and widespread urbanization. During the early 1980s, 18% of China’s population lived in cities, but this rose to 39% by 2003, while the number of cities increased from 190 to 660 (including about 170 cities with a population greater than 1 million) over the same time period. From 1980 to 2003, the contribution of Chinese cities to gross national product (GNP) increased from 69.9% to 85.9% (Chinese Statistical Bureau 2004). However, urbanization has also led to serious environmental and ecological problems, both in urban and surrounding areas, including increased air and water pollution (Briant and Guo 2000; Liu and Diamond 2005; Shao et al. 2006), local climate alteration (Zhou et al. 2004), and a major reduction in natural vegetation cover and production (Fang et al. 2003). Urban residents have experienced an increase in levels of cholesterol-related diseases (Lee 2004) and an overall decline in quality of life. As the largest and most modern city, Shanghai has experienced extensive urban expansion over the past three decades (Figure 1a). Between 1975 and 2003, the city’s population increased from 10.8 million to 13.4 million (Shanghai Statistic Bureau 2004). The resulting ecological consequences of urban sprawl have caused considerable concern among scientists and policy makers. Several studies have documented some environmental impacts of Shanghai’s increasing urbanization; for example, an analysis of meteorological data from both the city’s 341