高CO2の海洋における生物学的炭素消費の増大
U Riebesell1, K G Schulz, R G J Bellerby
1Leibniz Institute of Marine Sciences, IFM-GEOMAR, 24105 Kiel, Germany. uriebesell@ifm-geomar.de
Nature
|November 13, 2007
まとめ
二酸化炭素 (CO2) 濃度の上昇による海洋酸化は,プランクトンコミュニティの炭素消費を増大させる. この増加した吸収は,炭素と窒素の比率と有機炭素の損失に影響を与え,海洋生態系に影響を与えます.
科学分野:
- マリン・バイオロジーの海洋生物学
- 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
背景:
- 海洋は大気中の二酸化炭素 (CO2) を大幅に吸収し,海洋酸性化と炭素酸 saturation の減少につながります.
- 予想されるCO2上昇は,海洋生物,特に化生物を脅かし,生態系レベルでの影響はほとんど不明である.
研究 の 目的:
- プランクトンコミュニティの溶けた無機炭素消費量に対する高濃度の二酸化炭素 (CO2) の影響を調査する.
- 変化するCO2レベルが,海洋プランクトンにおける栄養素の吸収と炭素から窒素へのステキオメトリーにどのように影響するかを決定する.
主な方法:
- 異なるCO2偏圧 (350,700,1,050マイクロアトム) の下で自然プランクトン群を維持するためにメソコスムの囲みを利用しました.
- メソコスム内の溶解した無機炭素の消費と栄養素の吸収を監視した.
- 炭素から窒素への吸収と有機炭素の損失のステキオメトリを分析した.
主要な成果:
- プランクトンコミュニティの溶けた無機炭素の消費量は,CO2レベルが上昇するとともに,高濃度で39%まで増加しました.
- 栄養素の摂取量は,異なるCO2処理において一定であった.
- 炭素:窒素の減量比は,二酸化炭素が上昇すると大幅に増加し,レッドフィールド比を超え,より大きな有機炭素の損失を示した.
結論:
- プランクトン群は,二酸化炭素が増加した条件下で,炭素の消費量が増加しています.
- CO2の増加は,海洋の炭素循環を変化させ,生態系の構造と機能に潜在的な影響を及ぼします.
- 海洋における生物学的フィードバックは,世界の炭素循環と気候変動において重要な役割を果たしています.
関連する概念動画
The Carbon Cycle
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
Bioremediation
Bioremediation is the use of prokaryotes, fungi, or plants to remove pollutants from the environment. This process has been used to remove harmful toxins in groundwater as a byproduct of agricultural run-off and also to clean up oil spills.
Oxygen Transport in the Blood
Hemoglobin (Hb) is a crucial molecule in the human body, consisting of four polypeptide chains, each bound to an iron-containing heme group. This unique structure enables hemoglobin to bind to oxygen, with each molecule capable of combining with four molecules of oxygen, leading to rapid and reversible oxygen loading. When fully loaded with oxygen, it is called oxyhemoglobin, while hemoglobin that has released oxygen is called reduced hemoglobin or deoxyhemoglobin. As hemoglobin binds oxygen,...
Carbon Dioxide Transport in the Blood
Carbon dioxide (CO2) transport in the blood is critical to human physiology. On average, our body cells produce around 200 mL of CO2 per minute, precisely the quantity expelled by the lungs. This process involves the transportation of CO2 from the tissue cells to the lungs in three primary forms.
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
Forms of CO2 Transport
1. Dissolved in plasma: A small percentage (7-10%) of CO2 is transported and dissolved directly in the plasma.
2. Carbaminohemoglobin: Just over 20% of CO2 is chemically bound to...
Carbon-dioxide Fixation
Carbon dioxide fixation in prokaryotes enables the assimilation of inorganic carbon into organic molecules, supporting biosynthetic pathways, sustaining ecosystems, and contributing to the global carbon cycle. It also has industrial applications in carbon capture and bioproduct synthesis. Autotrophic organisms rely on this process to utilize CO₂ as a carbon source in diverse environments.The Calvin CycleThe Calvin cycle is the most widespread carbon fixation mechanism, primarily used by...
Marine Microbial Ecology
Marine microbial ecosystems are shaped by distinct physicochemical limits, including high salinity, low nutrient availability, and fluctuating oxygen levels. These conditions favor smaller microbial cell sizes, which maximize their surface-to-volume ratio for efficient nutrient uptake.Microbial activity and community composition are closely linked to biogeochemical cycles, particularly in dynamic environments like estuaries, where halotolerant microbes thrive in response to variable salinity...


