How Does Soil Pull Carbon out of the Atmosphere?

Amidst concerns about catastrophic climate change, carbon sequestration is all the rage these days. Carbon sequestration is basically the process of pulling carbon out of the atmosphere and storing it natural reservoirs such as soil. Below ground, soil a counts for about 46% of total terrestrial carbon sequestration. How does it work?

The Simple Answer: Microbes Lock It Up

The simple answer is: microbes absorb the carbon and hold it. The process starts with photosynthesis, when plants “inhale” carbon dioxide from the atmosphere and use it to make sugars.

Then, they send 30–40% of their hard-earned sugars down into the soil as offerings their microbial allies. They literally give it away because those microbes are so valuable and vital to them, but more on that later.

The microbes (mainly soil fungi, and to a lesser extent, bacteria, protozoa, nematodes) take the carbon and “lock it up” in the form of recalcitrant organic matter or they store it within their bodies, mainly in fungal networks.

Through this ancient natural process, carbon is pulled from the atmosphere and stored away in the soil. That is, until a human comes along and disturbs or tills that soil and releases the carbon back into the air again.

If you want to understand a few more details about this process (in plain language), read on.