Carbon Cycle Diagram: Labeled Reservoirs & Processes
Describe the carbon cycle diagram you need and create an editable teaching draft. Use the labeled reference below to check the reservoirs, process labels, and direction of every arrow.
SEE ACADRAW IN ACTION
Science drawing, from idea to editable figure
Create a science illustration with AI. Refine drawings, build editable diagrams, and convert images to SVG.
Demos play as you scroll into view. Choose a feature to explore.
Trusted by students & researchers from 480+ universities
A global community spanning 60+ countries and regions, from QS top-ranked universities to leading research institutes
University logos belong to their respective institutions and are shown solely to illustrate our user community. They do not imply any partnership or endorsement.
Tool overview
Explore the use cases, workflow, and key things to know.
A labeled reference
Follow carbon between the atmosphere, living things, soil, fossil fuels, and the ocean.
Every arrow explained
Check each transfer against a source–process–destination table.
Make your own diagram
Describe your lesson or worksheet, then review, refine, and export the result.
Carbon cycle diagram labeled
Follow the carbon, one arrow at a time
A carbon cycle diagram shows where carbon is stored and how it moves. The boxes and illustrations are reservoirs; the arrows are transfers. This simple carbon cycle diagram combines the fast biological cycle, ocean exchange, and a long-term fossil-carbon pathway.
- Atmosphere
- Carbon dioxide (CO₂) in the air supplies carbon for photosynthesis. It also receives carbon from respiration, decomposition, combustion, and ocean release.
- Plants and animals
- Plants build organic molecules from CO₂. Animals obtain organic carbon through food. Both plants and animals carry out cellular respiration.
- Soil and dead organic matter
- Litter, roots, waste, and dead organisms add carbon to soil. Decomposers break down organic matter; their respiration returns some carbon to the air as CO₂.
- Fossil fuels
- Coal, oil, and natural gas store ancient organic carbon. Their formation requires particular burial conditions and geological time; most dead matter does not become fossil fuel.
- Ocean
- CO₂ moves across the air–sea surface in both directions. Ocean carbon also occurs in dissolved bicarbonate and carbonate, marine organisms, and sediments.
- Rocks and sediments
- Carbonate rocks and sediments are major long-term stores. They are outside this introductory figure; add weathering, burial, and volcanic return for a fuller geological model.
Fast and slow carbon cycles
One cycle, different timescales
Carbon does not follow one fixed loop at one fixed speed. The same reservoir can participate in fast exchanges and retain some carbon for much longer.
- Fast biological transfers
- Photosynthesis, feeding, respiration, and decomposition move carbon through organisms and their environment. Turnover ranges from short biological timescales to much longer storage in biomass and soils.
- Slow geological transfers
- Burial, sediment formation, rock weathering, and volcanic activity connect the surface with long-term stores over geological timescales. The burial arrow is a simplified organic-carbon pathway, not the whole slow cycle.
- Human influence
- Fossil fuel combustion transfers carbon out of long-term stores into the atmosphere. Deforestation also releases stored carbon and can reduce uptake by vegetation. Neither process creates new carbon.
Carbon cycle processes
Check every arrow in one table
Read each row as “carbon moves from this reservoir, through this process, to that reservoir.” The source and destination matter as much as the label.
| Carbon starts in | Process | Carbon moves to |
|---|---|---|
| Atmospheric CO₂ | Photosynthesis | Plants |
| Plants | Feeding | Animals |
| Plants | Plant respiration | Atmospheric CO₂ |
| Animals | Animal respiration | Atmospheric CO₂ |
| Plants | Dead plant matter | Soil organic carbon |
| Animals | Waste and dead matter | Soil organic carbon |
| Soil organic carbon | Decomposition and microbial respiration | Atmospheric CO₂ |
| A small fraction of buried organic matter | Burial and transformation over millions of years | Fossil fuels |
| Fossil fuels | Combustion | Atmospheric CO₂ |
| Atmospheric CO₂ | Ocean uptake | Ocean carbon |
| Ocean carbon | Ocean release | Atmospheric CO₂ |
How it works
Create your own carbon cycle diagram
- Step 1
Describe the scope
Specify the teaching level, reservoirs, and processes. Ask for a simple biological cycle or a more detailed model with oceans and geological storage.
- Step 2
Generate and check
Create a draft, then follow every arrow with the table above. Check that photosynthesis enters plants and that plant respiration returns carbon to the air.
- Step 3
Refine and export
Correct labels, separate crossing arrows, and review the science against your course references before exporting for a worksheet or presentation.
FAQ
Carbon cycle questions
What is a carbon cycle diagram?+
A carbon cycle diagram maps carbon reservoirs and the processes that move carbon between them. A basic labeled diagram includes atmospheric CO₂, plants, animals, soil, and arrows for photosynthesis, feeding, respiration, and decomposition. More detailed diagrams add ocean exchange, fossil fuels, and geological pathways.
What labels should a simple carbon cycle diagram include?+
Start with atmosphere, plants, animals, and soil or dead organic matter. Label the arrows photosynthesis, feeding, respiration, and decomposition. Add fossil fuels and combustion, plus two-way ocean exchange, if those processes are part of your assignment. There is no single universal number of stages.
Which way does the photosynthesis arrow point?+
It points from atmospheric CO₂ to plants in a land-based diagram, because photosynthesis incorporates carbon dioxide into organic molecules. Plant respiration is a separate transfer pointing back toward the atmosphere. Aquatic producers also photosynthesize using carbon available in water.
Do plants respire as well as photosynthesize?+
Yes. Plants perform cellular respiration during the day and at night. Keep the plant-respiration arrow separate from photosynthesis: photosynthesis takes up CO₂, while respiration releases CO₂.
How do decomposition and combustion differ?+
Decomposition is the biological breakdown of dead matter and waste. Microbial respiration during decomposition releases CO₂; oxygen-poor conditions can also produce methane. Combustion is burning fuel or biomass, rapidly transferring stored carbon to gases including CO₂. They need distinct labels.
Is the ocean only a carbon sink?+
No. CO₂ crosses the ocean surface in both directions, so a diagram should show uptake and release. The global ocean currently absorbs more CO₂ than it releases overall, but the balance varies by place and time. A net sink can still have outward carbon flows.
Does all dead organic matter become fossil fuels?+
No. Much organic matter is consumed or decomposed. Only a small fraction is preserved under suitable burial conditions and transformed over geological time. Label fossil fuel formation as a long-term pathway rather than the next inevitable step after decomposition.
Can I generate an editable carbon cycle diagram?+
Yes. Describe your diagram in the AcaDraw input above, generate a draft, and refine the labels and layout before exporting. Generation requires an account and available credits. AI output needs review: use the process table and references to check the result.
Method and references
How this reference was prepared
The explanations follow NASA Earth Observatory and OpenStax Biology 2e. The teaching figure combines AI-generated reservoir artwork with explicitly drawn arrows and labels. It is a simplified reference, has not been independently peer-reviewed, and omits carbonate-rock pathways, methane transfers, and flux measurements. Check course-specific requirements before using it.
Last checked: 2026-10-19
Verification resources
Carbon cycle diagram generator
Make the diagram your lesson needs
Start with the reference, then describe the reservoirs, labels, and level of detail you want. Generate a draft and review each carbon transfer before using it.
How to Draw the Carbon Cycle
Build the diagram in five steps, avoid reversed arrows, and use the printable checklist.
Rock Cycle Diagram
Explore another Earth-system cycle, with labeled rock types and the processes connecting them.
Scientific Diagram Generator
Create editable teaching and research diagrams for other scientific topics.