How the Carbon Cycle Works

The law of conservation of mass teaches us that matter cannot be destroyed.  It can only change forms.

This principle has many practical applications.  Some of them have to do with agriculture.  For example, the carbon cycle.

How It Works

1. Plants absorb carbon dioxide from the atmosphere during photosynthesis.
2. The carbon dioxide is converted into plant cells.
3. Animals and humans eat the plants and thereby take in carbon.
4. This carbon is then exhaled and released back into the atmosphere for plants to use again.
5. If the plant dies without being eaten, it decomposes and its carbon goes into either the soil or the atmosphere.
6. Carbon in the soil may eventually be returned to the cycle through ingestion and respiration by microorganisms.
7. Soil carbon may also enter the water supply through erosion, eventually making its way to the ocean either to be returned to the atmosphere or to feed marine plants and animals.
8. Some of the carbon in the soil remains in place for many years, however.  Depending on conditions it may be converted to coal, oil, natural gas, or sedimentary rocks.
9. At this point, the carbon can be returned to the cycle either through volcanic activity or human intervention in the form of burning fuel.  In either case, the carbon once again returns to the atmosphere to start the cycle over again.

What This Means to the Farm

As you probably guessed, the carbon cycle is very important to the farm.  It is necessary to support plant life, which in turn is necessary to support animal and human life.

Part of stewarding the carbon cycle is capturing its full potential.  For example, most farmers try to avoid soil erosion, which moves valuable carbon off of the farm.  It will not go to waste (conservation of mass, remember?), but it will be lost to the farmer in question, reducing his ability to grow the plants and animals that make up his livelihood.

Another example of making use of the carbon cycle is composting.  In composting, gardeners take dead plants and allow them to decompose in a place where their carbon and other nutrients can be collected for later use.

This is also part of the principle behind the viewpoint that sees a pasture as a solar panel.  A swath of grass containing carbon is grazed by livestock, who then exhale the carbon they consumed.  This carbon is returned to the carbon cycle where it can go on feeding that pasture full of plants.

Nature is full of checks and balances.  Keep your eyes open for them.  You’ll be amazed at the useful information you will gather for your farm.