河川での微量金属輸送のメカニズム

R J Gibbs

Science (New York, N.Y.)

|April 6, 1973

まとめ

アマゾン川とユコン川の微量金属は,固体やコーティングなどの輸送段階に類似して分布しています. 銅とクロムは結晶固体を好み,マンガンはコーティングに含まれています.

科学分野:

環境科学環境科学
地質化学地質化学
アナリティカル・ケミストリー (Analytical Chemistry) とは

背景:

川は,世界的に微量金属輸送の重要な経路である.
微量金属の分割を理解することは,水生生態系の健康にとって極めて重要です.
アマゾン川とユーコン川は,世界の主要な堆積物と溶液の輸送手段である.

研究の目的:

アマゾン川とユーコン川の様々な輸送段階の間で微量金属を分析的に分割するために.
この2つの主要な河川系における微量金属の分布パターンを比較する.

主な方法:

微量金属を溶液,イオン交換,有機物質,金属コーティング,結晶固体に分割する分析方法.
各フェーズにおける金属濃度を正確に定量化するために,高度な分析技術を使用しています.

主要な成果:

トレースメタルの分布は,アマゾン川とユーコン川の間で同様の割合を示しました.
銅とクロムは主に結晶固体の中で運ばれた.
マンガンは主に金属コーティングと関連していたが,鉄,ニッケル,コバルトはコーティングと固体間で均等に分布していた.

結論:

トランスポートメカニズムと微量金属の分割は,アマゾンやユコンのような大きな,独特の河川システムで比較可能なパターンを表しています.
川の微量金属輸送は,固体相関連,特に結晶固体および金属コーティングによって大きく影響されています.

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