土地利用の歴史が,米国の森林における炭素蓄積に与える貢献
J P Caspersen1, S W Pacala, J C Jenkins
1Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08540, USA. jpc@eno.princeton.edu
Science (New York, N.Y.)
|November 10, 2000
まとめ
森林の炭素蓄積は,主に土地利用の変化によって引き起こされ,CO2や気候要因による樹木の成長が促進されない. この研究は,土地利用が支配的な力であり,成長の促進は森林の炭素貯蔵に小規模な役割を果たしていることを示しています.
科学分野:
- 林業科学 林業科学とは
- エコロジー エコロジー エコロジー
- 気候変動に関する研究
背景:
- 森林の炭素蓄積は,土地使用の歴史とCO2肥料化,窒素堆積,気候変動などの環境要因の影響を受けています.
- これらの要因が森林の炭素吸収に及ぼす相対的な影響は,生態学研究の重要な分野であり続けています.
研究 の 目的:
- アメリカ合衆国東部における森林の炭素蓄積に,歴史的な土地利用の変化と成長の強化の貢献を定量化するために.
- 二酸化炭素の肥料化,窒素の堆積,気候変動が木の成長と,その後の炭素貯蔵に与える影響を評価する.
主な方法:
- 緯度グラデーションに沿った5つの米国東部州の森林在庫データを活用した.
- 歴史的な土地利用パターンを分析し,木の成長促進効果を推定した.
主要な成果:
- 土地利用の変化は,研究された森林における炭素蓄積を牽引する支配的な要因として特定されました.
- CO2の肥料化,窒素の堆積,そして気候変動による成長の促進は,以前に推定されたものより著しく少なく貢献した.
- 成長の促進による地上環境の純生態系生産の割合は2.0 +/- 4.4%と計算された.
結論:
- 歴史的な土地利用の変化は,米国東部における森林の炭素蓄積の主な原動力である.
- 樹木の成長と炭素の蓄積を促進する二酸化炭素の肥料化,窒素の堆積,気候変動の役割は,しばしば報告されるよりも少ない.
- 将来の森林の炭素管理戦略では,土地利用の考慮を優先すべきである.
関連する概念動画
01:14The 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.
01:50Global Climate Change
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.
01:50Threats to Biodiversity
There have been five major extinction events throughout geological history, resulting in the elimination of biodiversity, followed by a rebound of species that adapted to the new conditions. In the current geological epoch, the Holocene, there is a sixth extinction event in progress. This mass extinction has been attributed to human activities and is thus provisionally called the Anthropocene. In 2019 the human population reached 7.7 billion people and is projected to comprise 10 billion by...
02:22The Colonization of Land
Changes in the environment of the early Earth drove the evolution of organisms. As prokaryotic organisms in the oceans began to photosynthesize, they produced oxygen. Eventually, oxygen saturated the oceans and entered the air, resulting in an increase in atmospheric oxygen concentration, known as the oxygen revolution approximately 2.3 billion years ago. Therefore, organisms that could use oxygen for cellular respiration had an advantage. More than 1.5 years ago, eukaryotic cells and...
01:27Microbes and Climate Change
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...