西部熱帯太平洋の生体活性微量金属に関する研究（1）

• Published in: Bulletin of the Society of Sea Water Science, Japan Vol. 64; no. 2; pp. 99 - 108
• Main Authors: 中口 譲, 藤田 昭紀, 中川 蓉子, 下島 公紀
• Format: Journal Article
• Language: Japanese
• Published: 日本海水学会 2010; The Society of Sea Water Science, Japan
• Subjects: Bioactive trace metals; ICP-MS; Nutrients; the Western Tropical Pacific Ocean; 栄養塩; 生体活性微量金属; 西部熱帯太平洋
• ISSN: 0369-4550; 2185-9213
• DOI: 10.11457/swsj.64.99

This paper describes the vertical profiles of dissolved bioactive trace metals such as Fe, Cd, Cu, Ni, Zn and Co in the Western Tropical Pacific Ocean. The behavior and profile of bioactive trace metals were classified into three types. 1) Nutrient type behavior and profile (Cd, Ni). 2) Extremely high concentration at the surface with the concentration decreasing linearly from 10m to the bottom (Cu, Zn), 3) Distribution and behavior are different at each sampling station (Fe, Co). Significant correlations were observed between Cd, Ni and nutrient concentrations. The average concentrations of Cd, Cu, Zn, Ni and Co below 2000m in the Western Tropical Pacific were lower than those in the North Pacific Ocean. The origin of the air mass above 1500m at four stations was off shore. The air mass above 1500m at only one station passed through the New Britain Island. Thus, the dissolved Cu and Zn at the surface might be supplied from materials other than these of terrigenous origin. 本論文では西部熱帯太平洋のFe, Cd, Ni, Cu, ZnそしてCoなど溶存態生体活性微量金属の鉛直分布を示した．生体活性微量金属の挙動及び分布は3つのタイプに分類された．1）栄養塩型の挙動と分布を示すもの（Cd, Ni），2）表層で極めて高濃度でしかも10m以深から深層にかけて濃度が直線的に増加するもの（Cu, Zn），3）分布，挙動が測点により異なる（Fe, Co）．Cd, Niと栄養塩濃度の間には極めて高い相関性が認められた．西部熱帯太平洋水深2000m以深のCd, Ni, Cu, ZnそしてCoの平均濃度は北太平洋に比べて低い値であった．4つ試料採取点上空1500mの気塊の起源は洋上であった．1測点のみ上空1500mの気塊はニューブリテン島上空を通過してきていた．その結果，表層における溶存CuおよびZnは陸起源以外の物質から供給されたと考えられた．