西太平洋邊緣海銀之分佈研究

Abstract

本研究分析西太平洋邊緣海〔東海、南海、西菲律賓海、台灣海峽以及沿岸河口〕表水中的銀，探討銀在邊緣海的表層海水分佈情形；及分析探討銀的垂直剖面變化。研究結果顯示，台灣海峽表水與沿岸河口表水銀濃度較開放性海域西菲律賓海及北南海之表水濃度高，濃度範圍從0.5pM~65pM。在台灣海峽，濃度分佈從南往北濃度遞增；離岸往近岸河口遞增，可見沿岸河口受到人為污染影響導致濃度較高。 垂直剖面研究區域於北南海及西菲律賓海，共七個剖面。垂直剖面上層水銀濃度低而深層水濃度高，濃度範圍在7pM內，底層深海水濃度範圍最高將近37pM。銀的濃度垂直分佈，主要為營養鹽分佈型態，與矽酸鹽濃度成正向關係。因此大洋區銀的分佈主要應是受到浮游生物影響作用。菲律賓海向南海漸增，相較於北太平洋深層水並未有明顯增高情形，與西北太平洋研究相符，詳細地球化學現象仍有待進一步探討。

This study aims at the investigation of the spatial distribution and vertical profile of dissolved silver in the waters of the East China Sea, South China Sea and Philippine Sea. Results show that Taiwan Straits surface water and the coast of river silver concentrations are high to compare to the open ocean areas (the west Philippine sea and the north South China Sea). Silver concentrations range from 0.5~65pM. Silver distributions were characterized by decreasing long-shore southward and increasing near-shore concentrations near river mouths indicating anthropogenic inputs. Seven section vertical profiles of silver concentrations in the South China Sea and Western Philippine Sea show that silver concentrations are low in surface waters (< 7 pM) and relatively high (37 pM) in the deep waters. This nutrient-type distribution is further evidenced by the significant correlation of silver with silicate concentrations. Silver concentrations in the west Philippine sea gradually increase towards to the South China Sea, but they do not compare well to ours in the North Pacific deep water. Comparison to the northwest Pacific studies are discussed based on methodological differences.