鉄による亜北極植物プランクトンの繁栄の衰退と運命
Philip W Boyd1, Cliff S Law, C S Wong
1NIWA Centre for Chemical and Physical Oceanography, Department of Chemistry, University of Otago, PO Box 56, Dunedin, 9003, New Zealand. p.boyd@niwa.co.nz
Nature
|April 3, 2004
まとめ
鉄の受精は植物プランクトンの開花を促しますが,多くの固定炭素は深海の輸出ではなく,細菌や牧草動物に失われます. シリチウム酸の枯渇と非効率的な炭素転送の限界結合の可能性.
科学分野:
- 海洋学 海洋学とは
- バイオジオケミストリー バイオジオケミストリー
- 海洋生態学 海洋生態学
背景:
- ハイ・ナイトレット・ロー・クロロフィール (HNLC) の海洋地域は,しばしば鉄の利用可能性によって制限されています.
- 鉄によって刺激される植物プランクトンの開花は,海洋の炭素循環において重要な役割を果たします.
- これらの開花の後,地表水から海洋内部の炭素輸出の効率は,十分に理解されていません.
研究 の 目的:
- 鉄で刺激された藻の咲きによる微粒子有機炭素 (POC) の減少と運命を調査する.
- 炭素輸出効率を定量化し,損失経路を特定する.
- 過去の鉄の肥料化イベントと将来の炭素封じ込め戦略への影響を評価する.
主な方法:
- アラスカ湾で鉄添加後にダイアトームの開花をモニタリング.
- 混合層の有機炭素粒子 (POC) とシリカ粒子の測定.
- 50~125mの深さで輸出フローを定量化するための沈殿物トラップの展開.
- バクテリアの再鉱化とメゾゾープランクトンの放牧への影響の評価.
主要な成果:
- 鉄とシリチウム酸が枯渇したため,その咲きは終わりました.
- 混合層のPOCは,咲き終えた後に急速に減少した.
- 粒子状シリカの輸出の増加は,重要なPOCの輸出を先行した.
- バクテリアによる再鉱化と牧草は,POCの赤字の半分以上を占めました.
- 永久熱線線以下で輸出されたPOCはわずかでした.
結論:
- シリチウム酸の枯渇は,ダイアトムの開花期間と,その後の炭素輸出を制限する.
- 深海への鉄刺激炭素の輸出は非効率である.
- この発見は,地質的な鉄の肥料化と,海洋の炭素収縮方法について提案された仮定に異議を唱えている.
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