HEAVY METAL DISTRIBUTION PATTERNS IN CHINESE COASTAL SEDIMENTS AND ENVIRONMENT QUALITY ASSESSMENT

Geochemical data of heavy metal, such as As, Cd, Cr, Cu, Hg, Pb, Zn, from 6 094 stations of Chinese coastal surface sediments and 1 495 stations of deep sea sediments were collected for environmental quality assessment. The data were processed with multivariate statistics and other mathematical methods in order to better reveal the distribution pattern of heavy metal elements. Following the quality criteria of marine sediments setting up by the GB18668—2002, a comprehensive index method was adopted to evaluate the ecological vulnerability of heavy minerals in the coastal sediments. Results suggest that the clean areas for 79%, slightly polluted areas for 14%, and heavily polluted areas for 7% in China's coastal waters. The heavily polluted areas are located near Huludao, Liaoning Province and the Pearl River estuary, the slightly polluted area is near the Yangtze River estuary. Pollutants are mainly from human activities.