地球システムシミュレーションでは,プロテロゾイク時代の海洋はより緑色だったが,生産性が低いことが示唆されている
Peng Liu1,2, Yonggang Liu3, Lin Dong4
1Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Lab of Submarine Geosciences and Prospecting Techniques, Ministry of Education and College of Marine Geosciences, Ocean University of China, Qingdao, China.
Nature communications
|February 17, 2026
まとめ
海洋植物プランクトンはプロテロゾーイク時代に開花し,より緑の海を作り出した. しかし,この密集した植物プランクトンは日光を制限し,今日の全体的な海洋生産性を大幅に低下させた.
科学分野:
- パレオセアノグラフィー
- マリン・バイオジオケミストリー
- 気候モデリング
背景:
- 地質学的記録は,海洋植物プランクトンがプロテロゾイク時代に出現したことを示しています.
- 動物プランクトンは存在せず,海洋の生産性はかなり高かったが,定量的なデータは不足している.
研究 の 目的:
- プロテロゾイク時代の植物プランクトンバイオマスと純一次生産性を定量的に推定する.
- 地球システムモデルを使用して,プロテロゾーイクにおける海洋生地化学サイクルをシミュレートする.
主な方法:
- コミュニティ・アース・システム・モデルバージョン 1.2.2.2.を使用しました.
- プロテロゾイクシミュレーションのための改変された生物学的モジュールと境界条件.
- 異なる栄養素と環境条件下での海洋生地化学サイクルを分析した.
主要な成果:
- プロテロゾイク時代の植物プランクトンバイオマスは,現在の2倍以上で,より緑の海をもたらした.
- 顕著な"自己遮断"効果は,密度の高い表面クロロフィールにより,地表の純一次生産性を低下させた.
- 純一次生産性は,現在の水準の約60% (温暖期) と30% (寒冷期) であった.
結論:
- プロテロゾイク期の純一次生産性は,低窒素,藻類の欠如,および自己遮蔽によって制限されていました.
- プロテロゾイク期の海洋条件は,より高い植物プランクトンバイオマスにもかかわらず,全体的な生産性が低下しました.
- モデルの結果は,栄養分レベル,特にリンに対して敏感です.
関連する概念動画
Primary Production
25.7K
The total amount of energy acquired by primary producers in an ecosystem is called gross primary production (GPP). However, of this energy, producers use some for metabolic processes, and some is lost as heat, decreasing the amount of energy available to the next trophic level. The remaining usable amount of energy is called the net primary productivity (NPP). In terrestrial ecosystems, NPP is driven by climate, while light penetration and nutrient availability drive NPP in aquatic ecosystems.
25.7K
Conditions on Early Earth
102.1K
Around 4 billion years ago, oceans began to condense on earth while volcanic eruptions released nitrogen, carbon dioxide, methane, ammonia, and hydrogen into the primordial atmosphere. However, organisms with the characteristics of life were not initially present on earth. Scientists have used experimentation to determine how organisms evolved that could grow, reproduce, and maintain an internal environment.
102.1K
The Soil Ecosystem
25.1K
Plants obtain inorganic minerals and water from the soil, which acts as a natural medium for land plants. The composition and quality of soil depend not only on the chemical constituents but also on the presence of living organisms. In general, soils contain three major components:
25.1K
What is Evolutionary History?
43.8K
Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.
43.8K
Green Algae
931
Green algae, also referred to as chlorophytes, are different from red algae in having the chloroplasts containing chlorophylls a and b, which give them their distinct green hue. However, they lack phycobiliproteins, preventing them from developing the red or blue-green pigmentation seen in red algae. In terms of photosynthetic pigment composition, green algae closely resemble plants and share a close evolutionary relationship with them. Taxonomically Green algae belong to Phylum Chlorophyta in...
931
Global Climate Change
29.1K
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
29.1K


