Most people believe we must stop burning fossil fuels to prevent further increases in atmospheric carbon. Many people also believe we need to find ways to remove carbon already in the air if we want to reduce the chance of weather crises and associated human tragedies, economic disruption and social conflicts that they bring.
The Case for Soil Carbon
Where can we put carbon once it is removed from the air? There is only one practical approach, and that is to put it back where it belongs, which is in the soil. Fortunately, this is not an expensive process, although it does take large numbers of people to agree to take part.
The reason carbon should go back into the soil is because the soil is literally alive. It is full of bacteria, fungi, protozoa, nematodes and many other creatures. In a teaspoon of healthy soil, in fact, there are more microbes than people on this earth. Yes, we said that—there are more microbes in a teaspoon of healthy soil than people on the earth!
Of course, carbon-based life forms require constant supplies of organic matter to survive. Approximately 58% of this organic matter is carbon, which comes in the form of living organisms, their exudates (simple sugars), and their residues (carbohydrates) like cellulose. These compounds are energy rich, readily accessible to organisms, and rapidly consumed by soil microbes in less than 1 hour.
How does carbon last in the soil?
If carbon is so rapidly consumed in soil, why does it last for so long? The answer is that plants are constantly renewing the supply of carbon. Since their evolution 3.5 billion years ago, plants have thrived by using their remarkable power to take carbon out of the air and put it into living matter. This process is called photosynthesis and it is the driving force of the soil food web and most all life on earth.
When plants photosynthesize and make carbohydrates, they use some of those compounds for their cells and structure, while they burn the rest for their life energy. However, they exude a significant amount of these compounds as “liquid carbon” into the soil.
Hungry bacteria, fungi, and other soil organisms will quickly show up to devour the tasty carbon-containing root exudates. They soon want more, though, and so the best way to get them is to assist the plant in making more. When a plant is healthy and strong, it can devote more energy to photosynthesis and exude more carbon. Soil organisms aid the plant in many diverse ways to help it thrive and produce more carbon.
Use of synthetic chemical fertilizers seriously reduces or in many cases even eliminate any soil carbon buildup. The use of synthetic chemicals is destructive to the production of soil carbon. Toxic pesticides are lethal to soil organisms, that are crucial in enhancing plant vitality and photosynthesis.
Erosion by wind and water is a major enemy of soil carbon, so growing plants are your best protection against erosion. Plants not only protect soil carbon but add to it through their power of photosynthesis. Using toxic chemicals kills this entire process.
Want to learn more about soil carbon and the modern landscape? Read our next blog or call Heidelberg Farms at (603) 501-9919. Let’ get you started on an organic lawn care program this spring!