Environmental stresses, meanwhile, are already slowing China's economy. China is also short of fresh water. China is also putting great stress on its limited agricultural and forest lands. The rich arable land along the coastal plain is rapidly being covered with homes, factories, roads, and parking lots, while soil erosion has reduced the productivity of a sizable portion of the remaining lands. Moreover, demand for building materials and firewood has put similar pressures on China's forests.
International surveys find that five of the world's ten most air-polluted cities are found in China.
China's acid rain is also carried by the wind to Japan and South Korea, both of which claim that China now accounts for more than half the acid rain falling within their borders. Globally, China's rising emissions of greenhouse gases have placed it at the center of international debates over climate change. China is already the second largest producer of carbon dioxide, the leading greenhouse gas. Though its per capita emissions are currently one seventh those of the United States, future growth is projected to push its overall emissions past the US by 2020. The Framework Convention on Climate Change, signed in 1992, calls for industrial countries to hold greenhouse gas emissions in the year 2000 to 1990 levels, but includes no limits on developing countries.