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プレイストセンの水層を通るアルゼンチンの輸送の遅延
Alexander van Geen1, Benjamín C Bostick, Thi Kim Trang Pham
1Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA. avangeen@ldeo.columbia.edu
Nature
|September 13, 2013
まとめ
東南アジアにおける地下水の汲み上げは,安全なプレイストセンの水層を,浅いホロセンの水源からのヒ素で汚染しています. アルゼンチンはアルゼンチンを含んでいる.
科学分野:
- 環境科学 環境科学
- 水文地質学 水文地質学は,水文地質学である.
- 地質化学 地質化学
背景:
- 南アジアと東南アジアでは,何百万人もの人々が,浅いホロセンの水層から発するヒ素中毒に直面しています.
- プレイストセンの水層は,より古く,通常はアルゼンチンがなく,より安全な飲料水の代替品です.
- プレイストセンの水層における汚染の動態を理解することは,公衆衛生にとって極めて重要です.
研究 の 目的:
- ベトナム・ハノイ近郊のプレイストセンの水層におけるアルゼンチンの汚染の初期段階を再構築する.
- 地下水のポンプがプレイストセンの水層におけるヒ素濃度にどのように影響するかを調査する.
- 水層システムにおけるヒ素の輸送と遅延を制御する要因を評価する.
主な方法:
- 初期汚染段階の再構築.
- 地下水の流れ状況と酸化還元状態の変化の分析.
- 塩基層の砂に含まれるヒ素の吸収と輸送遅延の測定.
主要な成果:
- 地下水をポンプで汲み上げることで,ホロセンのアルゼン汚染 (>120m) がプレイストセンの水層に横向に侵入した.
- アクイフェアの砂にアルゼンチンの吸収は,輸送を大幅に遅らせ (16-20倍) ました.
- プレイストセンの水層のアルゼンチンの汚染は,輸送の遅延によって遅れる可能性があります.
結論:
- 地下水をポンプで汲み上げることで,浅い水源から,以前は安全な深層水層に,を移動させることができます.
- アルゼンチンの輸送は,吸収によって著しく遅れており,広範囲にわたる汚染を遅らせる可能性があります.
- 地下水資源の管理戦略は,ヒ素の動員と輸送のダイナミクスを考慮する必要があります.
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