Name: carbon movement in living systems
Uploaded: 2019-03-11T09:21:40.000Z
Duration: 1 min 14 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

NC K-12 Science Standard Course of Study

9-12

Biology

ecosystems-interactions-energy-and-dynamics

Ecosystems- Interactions, Energy, and Dynamics

LS.Bio.4.1

The Carbon Cycle

炭素循環とは、炭素の原子が生態系を移動することを指します 植物のような独立栄養生物が、光合成によって 大気中の炭素を二酸化炭素から 消費エネルギーへと変化させます このエネルギーは有機栄養生物に摂取されます こうした有機体は、呼吸によって炭素を大気中に戻したり、腐敗によって炭素を土に戻したりします 大気中の二酸化炭素は、水によく解けるので 海は炭素の主な貯蔵地となっています 水と反応した二酸化炭素は、炭酸となり、やがて炭酸イオンとなります 海水に含まれる炭酸カルシウムは、サンゴ骨格や軟体動物の殻となります また炭素は、寿命の長い樹木や土の中に 短期間保存されます また、化石燃料ではより長期間保存されます 化石燃料は、昔生きていた有機体の残骸から出来ています 最後に、炭素は地層や地殻の中に保存され、マグマへと溶けていきます 火山の噴火の際に大気中へと放出され、これを脱ガスと呼びます

Brüggemann, N., A. Gessler, Z. Kayler, S. G. Keel, F. Badeck, M. Barthel, P. Boeckx, et al. "Carbon Allocation and Carbon Isotope Fluxes in the Plant-Soil-Atmosphere Continuum: A Review." Biogeosciences 8, no. 11 (2011年11月28日): 3457-89.[<a href="https://doi.org/10.5194/bg-8-3457-2011" target="__blank">ソース</a>]

Baldocchi, Dennis, Youngryel Ryu, and Trevor Keenan. "Terrestrial Carbon Cycle Variability." F1000Research 5 (2016年9月26日): 2371.[<a href="https://doi.org/10.12688/f1000research.8962.1" target="__blank">ソース</a>]

炭素循環

炭素は、地球上のすべての有機物の基礎であり、生物間で交換される過程と、有機物の化石化、岩石の風化、火山活動などによって長い時間をかけて循環する過程の2つの主要な過程で、生態系の中でリサイクルされています。しかし、農業の増加や化石燃料の燃焼など、人間の活動が自然の炭素循環のバランスに大きな影響を与えています。
 
 <h4>生物学的炭素循環</h4>
 
 すべての生物は、炭素元素の原子を含む有機分子で構成されています。炭素は大気中では二酸化炭素として存在し、水と反応して炭酸水素塩を形成します。一次生産者（独立栄養生物）は、光合成によって二酸化炭素と炭酸水素塩をグルコースなどの有機炭素化合物に変換し、成長や維持などのエネルギー源とします。
 
 従属栄養生物は、成長や維持のための有機炭素を、独立栄養生物を食べることによって受け取ります。このプロセスの副産物は水と二酸化炭素で、これらは呼吸によって大気中に放出され、循環を続けます。
 
 炭素は、動物の排泄物や生物の死骸の腐敗物としても環境に戻ます。細菌や菌類などの分解者は、これらの物質を二酸化炭素と有機化合物に分解します。
 
 <h4>長期的な地中循環</h4>
 
 炭素は、大気中、大水域、海洋堆積物、土壌、動物の化石、地球内部などに長期間にわたって蓄積されます。大気中の二酸化炭素は海中に溶け込み、水分子と反応して炭酸塩に変化します。この炭酸塩がカルシウムイオンと結合して、サンゴやカキなど多くの海洋生物の炭酸カルシウムの殻を構成しています。これらの生物が死ぬと、その遺骸は分解されて海底に沈み、次第に堆積物の一部となることがあります。この堆積物は最終的に石灰岩を形成し、地球上で最大の炭素貯蔵庫を構成します。
 
 寿命の長い大木は、何世紀にもわたって体内に炭素を蓄えることができます。生物の遺骸は、より長期的な吸収源（炭素貯蔵庫）として、石炭、石油、天然ガスなどの化石燃料の形で、何百万年もかけて地球の奥深くに炭素を貯蔵しています。地表の奥深くに蓄えられた炭素は、火山の噴火によって地表や大気中に戻ってきます。
 
 <h4>人間による炭素循環への影響</h4>
 
 化石燃料や木材の燃焼により、大量の二酸化炭素が大気中に放出され、地球の気候を変化させています。さらに、森林伐採や農業の増加は、土壌中の有機物の量を減らし、炭素の貯蔵量を減少させ、大気中のメタンなどの温室効果ガスのレベルを上げることで、自然の炭素循環に影響を与えています。

炭素は地球上のすべての有機物の基礎であり、生態系を通じて2つの主要なプロセスでリサイクルされます。

Education

JoVE Core

生物学

Ecology

生態学

Ecosystems

生態系

KEY TERMS AND CONCEPTS

主要用語と概念

carbon movement in living systems

Carbon moves through living systems and Earth over short and long time scales. It is the basis of all organic matter on Earth, and it cycles through ecosystems by passing between organisms and by moving through rocks, oceans, and the atmosphere. Human activities, including farming and burning fossil fuels, have changed this balance.

In the biological carbon cycle, carbon dioxide in the atmosphere reacts with water to form bicarbonate. Primary producers, or autotrophs, use carbon dioxide and bicarbonate during photosynthesis to make organic compounds such as glucose. These carbon-containing molecules support growth, maintenance, and other life processes.

Heterotrophs get organic carbon by eating autotrophs. They break down these molecules during cellular respiration to release stored energy. Water and carbon dioxide are the main byproducts, and the carbon returns to the atmosphere through respiration. Carbon can also leave organisms as waste or as dead matter. Decomposers, such as bacteria and fungi, break this material down and release carbon dioxide and organic compounds back into the environment.

Carbon also moves through long-term geological storage. It can remain in the atmosphere, large water bodies, ocean sediment, soil, fossilized animal remains, and deep inside the Earth for long periods. In the ocean, dissolved carbon dioxide reacts with water and becomes carbonates. These carbonates combine with calcium ions to form calcium carbonate shells in marine organisms such as coral and oysters. When these organisms die, their remains can sink and become part of sediment, which may later form limestone, the largest carbon reservoir on Earth.

Large, long-lived trees can store carbon in their bodies for centuries. On much longer time scales, the remains of organisms become fossil fuels, including coal, petroleum, and natural gas, deep in the Earth. Carbon stored underground can return to the surface and atmosphere during volcanic eruptions. Burning fossil fuels and wood releases large amounts of carbon dioxide into the atmosphere, which affects global climate. Deforestation and increased agricultural practices also change the natural carbon cycle by reducing soil organic matter, lowering carbon storage, and raising greenhouse gases such as methane.

Carbon Movement in Living Systems

what is an ecosystem?

Ecosystem Zones and Climate

Ecosystems are shaped by living and nonliving parts of an environment, and they can be grouped as terrestrial or aquatic. Terrestrial ecosystems depend on climate. Aquatic ecosystems are divided into freshwater and marine systems, and depth affects water temperature and how much sunlight reaches the water. Terrestrial ecosystems are called biomes. A biome is defined by climate and by the organisms that live there. Near the equator, rainforests have high, aseasonal temperatures and high annual...

trophic levels

Food Chains and Energy Flow

Food chains show how energy and nutrients move through an ecosystem. Each organism holds a trophic level, or a specific place in that chain. The lowest level includes primary producers, which make their own food using energy from the sun or from chemicals. Organisms at the next levels are heterotrophs, which get energy from other organisms below them. Primary consumers are herbivores, and they feed on autotrophs, also called primary producers. Secondary and tertiary consumers are carnivores...

primary production

GPP, NPP, and Ecosystem Energy

Gross primary production and net primary production describe how energy enters and moves through ecosystems. Primary producers, or autotrophs, make their own food. They can do this by photosynthesis or chemosynthesis, and they can also gain energy by consuming other organisms. The rate at which producers capture and store this energy is called gross primary production, or GPP. Not all of the energy in GPP stays available to the rest of the ecosystem. Primary producers use some energy for...

production efficiency

Energy Transfer as Biomass Efficiency

Net production efficiency shows how much energy organisms turn into biomass for the next trophic level. It focuses on the usable energy stored in body tissue, not the energy lost as heat or excreted wastes. This makes it a key idea for understanding energy flow through ecosystems. As energy moves from one organism to the next, only biomass can serve as food for the next trophic level. The rest of the energy is used in metabolism and is lost over time. Net production efficiency, or NPE, is the...

trophic efficiency

Energy Loss in Food Chains

Trophic level transfer efficiency describes how much energy moves from one level of a food chain to the next. It shows why energy drops sharply as organisms eat and are eaten. In most ecosystems, only about 10% of the energy passes on. This energy loss follows the second law of thermodynamics. In living systems, much of the energy is lost as metabolic heat during respiration. Trophic level transfer efficiency, or TLTE, measures this transfer by comparing the energy produced at one trophic...

what are biogeochemical cycles?

Nutrient Recycling in Ecosystems

Nutrient recycling in ecosystems keeps the elements needed for life moving through living and nonliving parts of the environment. Elements such as water, carbon, nitrogen, sulfur, and phosphorus are present in limited amounts, so they must be conserved and reused. These movements are called biogeochemical cycles. These nutrients can exist in several chemical forms. They may spend long periods in the atmosphere, on land, under the land, or in aquatic environments. Decomposition is a key part of...

the water cycle

Water Movement Through Earth Systems

Water movement through Earth systems connects the hydrosphere, the atmosphere, the land, and living things. The hydrosphere includes every place where water is stored or moves. Because water supports living processes, its movement is important for ecosystem dynamics. The cycle starts when the sun warms surface water on land and in the oceans. That water evaporates and enters the atmosphere as vapor. Water can also move into the air by sublimation, which is ice changing directly into vapor, and...

the carbon cycle

Carbon moves through living systems and Earth over short and long time scales. It is the basis of all organic matter on Earth, and it cycles through ecosystems by passing between organisms and by moving through rocks, oceans, and the atmosphere. Human activities, including farming and burning fossil fuels, have changed this balance. In the biological carbon cycle, carbon dioxide in the atmosphere reacts with water to form bicarbonate. Primary producers, or autotrophs, use carbon dioxide and...

the nitrogen cycle

Nitrogen in Soil and Living Things

Nitrogen in soil and living things moves through ecosystems in several forms. Nitrogen atoms are found in proteins and DNA. Most animals and plants cannot use nitrogen gas, which is the main form of nitrogen on Earth. Nitrogen must first be changed into a usable form by nitrogen-fixing bacteria before it can move through food webs. About 78% of the air we breathe is nitrogen gas, but few organisms can use it in that form. Nitrogen fixation changes nitrogen gas (N2) into ammonia (NH3).

the phosphorus cycle

Phosphorus Movement in Soil and Water

Phosphorus moves through ecosystems mostly as phosphate ions in soil, water, sediment, and rocks. Unlike carbon, water, and nitrogen, it is not found in the atmosphere as a gas. It is also often a limiting nutrient, which means it is in short supply in many environments. Phosphorus is important in DNA, cell membranes, bones, and teeth. It is found in minerals, sediment, volcanic ash, and aerosols. As rocks and sediment weather over time, they release inorganic phosphate. That phosphate then...

the sulfur cycle

Sulfur in Ecosystems and Acid Rain

Sulfur moves through ecosystems as part of the chemical cycle that supports life. It is an important element in proteins and in amino acids such as cysteine, which helps give proteins their structure. On land, sulfur reaches ecosystems in several ways. Weak sulfuric acid can fall with precipitation, sulfur can drop directly from the atmosphere, rocks can weather and release sulfur, and geothermal vents can add it as well. Plants and microorganisms take sulfur up from the soil and change it...

bioremediation

Bioremediation in Soil and Oil Cleanup

Bioremediation uses prokaryotes, fungi, or plants to remove pollutants from the environment. It is a practical way to reduce harmful chemicals in contaminated soil and water. In agriculture, fertilizers and pesticides can leach into groundwater, streams, and lakes. Microbes and bacteria can help break down these toxins. One example is atrazine, an environmental toxin found in many fertilizers, which can be removed from soils by the bacterial species Rhizobium and Tricoderma sp. Bioremediation...

key terms and concepts

Explore how carbon moves through photosynthesis, respiration, decomposition, oceans, rocks, and fossil fuels, and how human activity disrupts the cycle.

Carbon Movement in Living Systems | JoVE K12

JoVE Core series brings biology to life through over 300 concise and easy-to-understand animated video lessons that explain key concepts in biology, plus more than 150 scientist-in-action videos that show actual research experiments conducted in today’s laboratories.

biology

JoVE Core シリーズは、生物学の重要な概念を説明する 300 を超える簡潔でわかりやすいアニメーション ビデオ レッスンに加え、今日の研究室で行われる実際の研究実験を示す 150 以上の科学者の活動ビデオを通じて、生物学に命を吹き込みます。

Carbon Movement in Living Systems

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