Distributions of heavy metals in the sediment of coastal waters, southwestern Taiwan

• Main Authors: Yi-Yuan Peng, 彭議源
• Other Authors: Chiee-Young Chen
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/22901011136161494769

碩士 === 國立高雄海洋科技大學 === 海洋環境工程研究所 === 102 === This study is aiming to investigate the heavy metal concentrations, including As, Cd, Cu, Fe, Mn, Ni, Pb and Zn, in the sediment of southwestern Taiwan coastal waters. Sediment samples were collected, using research vessel OR-III equipped with a Smith-McIntyre Bottom Sampler, from March 2008 to August 2010. These samples were analyzed with an atomic absorption spectrometer (Hitachi Z-2000) to determine their metal concentrations. The concentrations of all the studied metals, except As, demonstrated significant geographical differences that the southern sites, Lin-yuan and Feng-liao, contain higher concentrations than those of the northern sites, Tai-si and Ci-gu. Nevertheless, no significant difference was observed between seasons or water depths. Based on the mean concentrations of earth’s crust, the enrichment factor (EF) of each heavy metal was then estimated. The EF values of Mn, Cu, Ni and Cd were all smaller than 1.5, and most of EF of the Pb and Zn were 1.5 ~ 3.0, while those of As located 8.8 ~ 21.3. However, when the EF were estimated based on regional background metal concentrations, majority of the EF were smaller than 1.5. Moreover, no geographical difference in the EF was observed. The geographical difference in metal concentrations but not in the corresponding EF may reflect that the heavy metal concentrations in the southern sites, Lin-yuan and Feng-Liao, are higher than those of the northern sites, Tai-si and Ci-gu, in nature. In comparison to the mean concentrations of earth’s crust, the concentrations of As, Pb and Zn in the sediment of southwestern Taiwan coastal waters also showed much higher values.