Carbon dioxide gets into the atmosphere from numerous sources, and when there’s too much of it, it causes global warming. That is a gross oversimplification, but the issue of global climate change is far too complex to fit into one sentence. Part of the reason it’s so complex is because there are a lot of parts of the process that we don’t understand very well yet. The role of soil in the process is one of those.
It may not seem, at first glance, that soil has a big part to play in climate change, but it actually holds onto a lot of carbon, which might otherwise get into the atmosphere and contribute to climate change.
While scientists have known for some time that soil acts as a carbon pool, they still don’t fully understand how much carbon soil can hold. Recent research implies that previous models of how much carbon can be stored in soil were inaccurate. Thus, they didn’t know how much carbon soil was holding, and how much it was releasing into the atmosphere (called carbon dioxide efflux).
While previous models were pretty accurate on barren or mesotrophic (moderately fertile) soils, they may have underestimated how much carbon could be held by more fertile soils. This means that many forests, which tend to have more fertile soil, could be helping to hold back even more carbon dioxide than we thought. That’s a good thing, until those forests get cut down.
Forestry, the science of maintaining forests, has traditionally been more concerned with not running out of resources, but increasingly has come to be concerned with the environmental effects of poorly managed forests. Cutting down swaths of forests that are holding onto significant amounts of carbon dioxide, could lead to much of that carbon entering the atmosphere.
Better understanding of soil as a carbon dioxide storage point will give scientists and foresters a better understanding of how to manage forests so that we don’t make climate change even worse through clear-cutting or other such practices.