Why soil carbon matters?
Soil carbon is the umbrella term for the carbon stored in the world’s soils. It includes soil organic carbon (SOC), the quantifiable carbon component of soil organic matter (SOM), which is synonymous with all living things such as plants, nematodes, fungi and bacteria that contribute to healthy soil, and to a lesser extent, inorganic soil carbon, which consists largely of mineral forms of carbon. A study from 2014 estimated that the carbon contained in the world’s soils is three times more than that contained in aboveground biomass, such as trees and plants, and 230 times higher than current man-made emissions.
A disrupted naturel cycle
Cities: a boon for civilisation, a blow to soil health
As the United Nations predicts that 68% of the world’s population will live in cities by 2050, it’s time to think about how our actions are affecting soil health and its ability to fight climate change.
As cities sprout and sprawl, nutrient-rich soil is removed and discarded as a waste product, wetlands are drained and vast areas of green space are compacted and paved. This not only affects soil chemistry, but also robs the soil of its resilience by making it impermeable to nutrients and water.
Food for thought…
Food production through industrial agriculture may increase soil productivity in the short term, but as we now know, it also plays a key role in undermining soil health, polluting water and contributing to climate change. We must rethink our practices to ensure a sustainable future for both ourselves and the planet.
Why it is vital to preserve and expand soil carbon?
Carbon-rich soils are a bulwark against food shortages, floods and climate change. In fact the climate depends on it. 25% of natural climate solutions rest on soil organic carbon. Simply protecting soil carbon would already contribute 40% of this amount, while the remaining 60% should consist of active strategies such as agroforestry and regenerative agriculture.
The use of high-residue cover crops and protection of wetlands are also exemplary measures to promote better carbon uptake. With the inexorable progress of the built environment, thoughtful urban planning and more green spaces that ultimately reduce the dreaded “urban heat islands” in summer must become the norm.