The lessening role of soil in the carbon cycle

The role of the soil in absorbing carbon and reducing the rate of global warming is now considered to be overestimated.

The thinking currently is that soils absorb up to 1/3 of the carbon being released through anthropogenic sources; helping to reduce the level of emissions in the atmosphere. It is also thought that increasing carbon levels in the atmosphere will lead to increased plant growth and therefore result in higher storage capacity in soils too. However, over 100 experiments carried out on varying soil types has found that this is not the case.

Typically, the storage of carbon in soils occurs over a bigger time scale than the storage in living things. As trees naturally die or deforestation occurs, the carbon stored there will be released as the vegetation decomposes, whereas soils store carbon for centuries.

Experiments carried out and reported in the journal Nature, found that when vegetation is exposed to higher carbon levels there was an increase of 23% more biomass taking in the carbon, however, there was no increase to the soil store.

The thinking that soils and the forest could act as a dampener on rising emissions has now been proved inaccurate, and leading climate experts are reinforcing the fact that the only real way to reduce the rising atmospheric temperatures is to tackle them at their source and cut emissions.

For more on this article, check out the following report:

One of Earth’s giant carbon sinks may have been overestimated - study | Soil | The Guardian