地球規模の炭素循環の陸から海へのループ
Pierre Regnier1, Laure Resplandy2, Raymond G Najjar3
1Biogeochemistry and Modelling of the Earth System-BGEOSYS, Department of Geoscience, Environment and Society, Université Libre de Bruxelles, Brussels, Belgium. pierre.regnier@ulb.be.
Nature
|March 17, 2022
まとめ
陸から海までの水質連続体 (LOAC) は,世界の炭素循環において重要な役割を果たしています. 人類の活動によって これらの流れが変化し 陸上と海洋の炭素貯蔵量に 影響を及ぼしています
科学分野:
- 環境科学
- 地球システム科学
- 生地化学
背景:
- 海洋と陸の炭素貯蔵は通常別々に評価され,陸から海洋の水中の連続体 (LOAC) は無視されます.
- LOACは内陸水域,河口,潮湿地,大陸棚水域を含み,炭素輸送を容易にする.
- 工業化前と人間による LOACの炭素循環を理解することは,正確なグローバルな炭素予算にとって不可欠です.
研究 の 目的:
- 陸から海への水域連続体 (LOAC) 内の工業化前と人間の影響による炭素の流れを定量化する.
- 地上と海洋の炭素貯蔵量に対する LOAC 炭素循環の影響を評価する.
- LOACフロースの評価を改善するための主要な知識のギャップを特定する.
主な方法:
- LOAC内の炭素移転を推定するために質量バランスアプローチを使用した.
- 産業化以前の炭素循環と 気候変動を含む人間の直接的干渉を分析した.
- 陸上生態系,内陸水域,潮湿地,大陸棚水域を炭素循環モデルに組み込みました.
主要な成果:
- 陸上の生態系からLOAC経由で海洋への工業化以前の純炭素転送は,年間0.65±0.30ペタグラムでした.
- 人類の活動により 陸地と内陸の水と大気の炭素循環が加速しています
- 人間の影響により 潮湿地や水中植生による炭素吸収が 減少しています
結論:
- LOACの炭素フローを無視すると,年間0.6±0.4ペタグラムの地球上の炭素貯蔵が過大評価されます.
- 現在の評価では,未解決のLOACダイナミクスにより,堆積物と海洋の炭素貯蔵が過小評価されています.
- LOACフロースの評価における不確実性を軽減するには,認識された知識のギャップに対処する必要があります.
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