|Abstract: ||本研究採用Tessier et al.(1979)的連續萃取法分析臺灣沿岸河口及臺灣海峽沉積物重金屬濃度，以了解其空間分佈及污染情形，連續萃取分析方法將沉積物重金屬濃度分成離子交換相(F1)、碳酸結合相(F2)、鐵錳氧化相(F3)、有機結合相(F4)與殘餘相(F5)。 臺灣沿岸河口及臺灣海峽沉積物各重金屬濃度範圍如下：鋁為2.923-9.478%，鈷為6.65-25.28mg/kg，鉻為23.48-142.93mg/kg，銅為6.97-146.83mg/kg，鐵為1.139-5.065%，錳為188.15-1170.38mg/kg，鎳為16.47-48.91mg/kg，鉛為11.51-32.96mg/kg，鋅為29.40-186.09mg/kg，汞為11.52-96.13ug/kg。除了銅元素外，臺灣海峽沉積物各重金屬元素的平均濃度皆高於臺灣沿岸河口的濃度，其原因可能是臺灣海峽沉積物粒徑較細、多為黏土，且其總有機碳濃度較高。使用富集因子(Enrichment Factor)與地理累積指數(Geoaccumulation Index)來判斷所分析沉積物重金屬的污染程度，計算結果顯示臺灣海峽及臺灣沿岸河口沉積物中之鈷、鉻、鎳與汞等元素有輕度污染的情況，其餘元素並無污染。 重金屬元素在五相的濃度分佈有明顯差異，鋁、鈷、鉻、銅、鐵、鎳、鋅與汞元素其濃度主要存在於殘留相(46.5-94.3%)，鉛主要存在於鐵錳氧化相(48.0%)，而錳元素則是以碳酸結合相濃度較高(33.1%)。|
The present study used the sequential extraction method published by Tessier et al.(1979) to analyze the concentrations of trace metals in sediments of the Taiwan estuarine mouth and the Taiwan Strait and to understand the spatial distribution and the pollution status of the analyzed trace metals. The sequential extraction method divides the concentrations of trace metals in sediments into five fractions, namely: (1) exchangeable; (2) bound to carbonates; (3) bound to Fe-Mn oxides; (4) bound to organic matter and (5) residual. The concentration ranges of trace metals in the analyzed sediment samples were as follows: Al, 2.923-9.478 %; Co, 6.65-25.28 mg/kg; Cr, 23.48-142.93 mg/kg; Cu, 6.97-146.83 mg/kg; Fe, 1.139-5.065 %; Mn, 188.15-1170.38 mg/kg; Ni, 16.47-48.91 mg/kg; Pb, 11.51-32.96 mg/kg; Zn, 29.40-186.09 mg/kg; Hg, 11.52-96.13 g/kg. The average concentration of trace metals, except Cu, in sediments of the Northern Taiwan Strait were generally higher than that of the Taiwan estuarine mouth. The reason for this is probably that the sediments of the Northern Taiwan Strait were mostly the clay and contained a relatively higher concentration of organic carbon. The enrichment factor and geo-accumulation index were employed to identify the contamination status of trace metals in the analyzed sediment samples. The calculated results suggest that the analyzed sediment samples were mildly contaminated by Co, Cr, Ni and Hg, the other elements were not contaminated. Based on the fractionation contribution of trace metal in sediments, the studied elements can be classified into three groups: Al, Co, Cr, Cu, Fe, Ni, Zn and Hg mainly dominated in the residual fraction; Pb mostly present the Fe-Mn oxides fraction; and Mn dominated in the carbonates fraction.