Study says we have over-estimated soil’s carbon storage capacity
There are many things that we take for granted in life. Among them is soil. Without soil’s incredible ability to generate food, we wouldn’t exist. Period.
It’s a quirk of life that often the things which are most significant to us- life sustaining things, like the air we breathe in- are the things that we least think about in our daily lives. It’s curious that this happens precisely because of our over-familiarity with such elements.
In the case of soil, for most of us, the familiarity is somewhat secondary in nature. For very few of us actually come in direct contact with food-producing soil, though we all consume foods which the soil brings forth. This is becoming even more true given the rapid pace at which urbanization is progressing in the world.
But whether we actually get to see food producing soil or not, there is one other aspect of soil which we have been taking for granted- and that’s soil’s ability to store up carbon.
Soil has been considered among the biggest carbon sinks in the earth. However, now, a new research shows that the ability of soil in storing carbon may be lesser than we had thought.
Soil as well as plants which grow out of it absorb one third of the carbon emissions which result in our present climate crisis. This helps offset the impact of burning fossil-fuel to some extent. When the carbon dioxide levels increase in the atmosphere, it could result in higher levels of growth of plants. We had assumed that this would naturally result in increased storage of carbon in soil.
However, the present study- based on more than a hundred experiments- show that’s not how things work.
The study shows that when plant growth goes up, the carbon levels stored in the soil do not.
The volume of organic carbon stored in soil is around thrice that which is stored in living plants. Also, it’s double the volume that’s in the atmosphere. Equally significant is the fact that carbon would be stored in the soil for centuries. Plants rot away much quicker than that.
As to how much this would affect the rate at which climate change progresses, there is no consensus yet. There are also warnings from experts regarding how climate emergencies like drought could affect the carbon storage capacity of soil and plants.
The study in question looked at over a hundred experiments from around the world. In these experiments, the soils and plants were exposed to higher levels of carbon dioxide compared with present day atmosphere.
The biomass in jungles increased by twenty three percent in experiments when the carbon di-oxide level was double that of pre-industrial levels.
That level is higher by fifty percent today. However, there was no resultant rise in the amount of organic carbon stored in the soil of the jungle.
