Heavy metal (Zn, Pb, Cu, Ni, Cr, Hg and As) concentrations were analyzed in surface sediments collected from the southwestern coast of Taiwan, the adjacent area of Anping Harbor, and the Tainan Canal. The results clearly indicate that smaller mean grain size and elevated mud content are observed close to Anping Harbor and fishing port. Grain-size normalized metal concentrations show large spatial variation, and metal distributions in the Tainan coastal sediments are clearly affected by terrestrial river inputs based on the locations of elevated metal concentrations. Heavy metal concentrations in the Tainan Canal sediments are significantly higher than those from the offshore area. Moreover, elevated Igeo (geo-accumulation index) values also indicate that the Canal sediments were either moderately or strongly contaminated with Zn and Hg. The varying metal concentrations in sediments near the mouth of Anping Harbor with data from December 2002 to January 2005, suggest no clear trends during phases I and II of dredging of the canal and no abnormal concentrations occurred during the dredging period. This result indicates that the metal contaminated sediments are trapped in the canal and then been removed during dredging.
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science
- Soil Science