まとめ
アマゾン川の有機物質には,爆弾炭素14が含まれているので,炭素の急速な循環が示唆される. 炭素14濃度の差異は,排水盆地内の炭素池の土壌保持の変動を示している.
科学分野:
- 地質化学 地質化学
- 環境科学 環境科学
- 放射性炭素年代測定法による年代測定
背景:
- アマゾン川は,その広大な排水盆地からかなりの量の有機炭素を輸送します.
- この有機炭素の年齢と循環を理解することは,世界の炭素予算の評価に不可欠です.
- 爆弾で生成された炭素14 (14C) は,最近の炭素投入量とターンオーバー率のトレーサーを提供します.
研究 の 目的:
- 爆弾で生成された14Cの存在と重要性について,アマゾン川の様々な有機炭素分数で調査する.
- 微粒子有機物質と溶けた有機物質の流通率を評価する.
- アマゾン流域の土壌プロセスが,輸出された炭素の14Cシグネチャーにどのように影響するか調査する.
主な方法:
- 粗細な suspended particulate organic matter (POM) の分析について. 粗細な suspended particulate organic matter (POM) の分析について. 粗細な suspended particulate organic matter (POM) の分析について. 粗細な suspended particulate organic matter (POM) の分析について.
- 溶けたヒウム酸とフルブ酸の分析.
- これらの分離した炭素分子の放射性炭素 (14C) 年代測定.
主要な成果:
- 爆弾で生成された14Cは,分析されたすべての分数:粗質POM,細質POM,ヒュミック酸,フルビック酸で検出されました.
- これらの共存する炭素形態の間で14C含有量の測定可能な差異が観察されました.
- この発見は,これらの材料を供給する親炭素プールの比較的速いターンオーバーを示唆しています.
結論:
- アマゾン川の有機炭素輸出は比較的若いもので,最近の大気14Cの影響を受けています.
- 14C濃度の差は,アマゾンの土壌内で炭素の保持と処理の度合いが異なることを示している.
- この研究は,大規模な河川システムにおける炭素動態の追跡における14Cの有用性を強調しています.
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