Acidification in China: Assessment based on studies at forested sites from Chongqing to Guangzhou

The rapid economic growth in China has been accompanied by a corresponding increase in pollution. In this paper the extent and effects of acid precipitation and precursors are discussed based on field observations and literature studies. Sulfur dioxide emissions are at present the major cause of acid precipitation, but emissions of nitrogen oxides are increasing. The deposition of sulfur compounds in the most polluted areas in China is higher than in parts of Eastern and Central Europe experiencing severe pollution. Soils and soil waters seem to be acidified in many areas in southern China. Pollution has affected the vitality of forests and other vegetation particularly in and close to urban areas. Surface water acidification is not likely to become a major regional problem in the near future, but streams in some areas, which currently receive little acid deposition, appear to be sensitive to acidification.