Few people are aware that a quarter of our world’s biodiversity lives in soil. A handful of soil alone can contain more than 50 billion living specimens – over six times the human population on this planet. Although many of these creatures are invisible to the naked eye, the bacteria, micro-fungi and insects that comprise soil populations are the stewards of soil health and consequently, all terrestrial life on earth.
Essential soils
Principally, soils are a combination of minerals and organic matter. The mineral elements can consist of clay, silt, sand, and stones and usually define a soil’s fertility, or quality to grow particular plants. As soils are needed to grow food and medicinal plants to sustain herbivores and omnivores, healthy soils are essential to life. Not only, are they a medium for growing crops, but healthy soils can store and filter water, protecting against both floods and droughts. Water run-off management is a much-needed climate adaptation solution as extreme weather events increase.
Furthermore, soils are the second-largest carbon store on earth after the world’s oceans. Plants absorb carbon dioxide through photosynthesis and the majority of this is stored as carbon in the plant roots. When organisms die, they decompose on top of - or within - soil, which adds to its humus content. Humus is the most carbon-rich portion of the soil. The key to locking carbon within soil is to keep it planted and bound together by root systems.
Sustainable soils
Generally, 24 billion tonnes of fertile soil is lost every year due to erosion. A leading cause of erosion is agriculture - when soils are left exposed to wind and rain due to poor land management practices (figure 1). Agriculture can also use aggressive chemicals that leach into soils, affecting soil fertility while contaminating groundwater.
Image Source: taken from Ecosystem Restoration Camps
Agriculture and soil working together – symbiotic saviours
The good news is, soils do not need to be abandoned to recover to a healthy, fertile, carbon-sequestering level. Regenerative agriculture techniques such as the use of cover crops, agroforestry and organic farming help soils to recover while continuing to remove carbon dioxide from the atmosphere. Video 1 shows how agroforestry has been used in the U.K. to improve soil quality. Farmer, Stephen Briggs reversed erosion and restored his farm's soil quality. Meanwhile, enhancing ecosystem services to run a profitable farm.
Video source: taken from The Woodland Trust
Furthermore, these techniques encourage biodiversity - providing habitats for vital pollinators and seed dispersers such as bees and small mammals. Which, in turn, benefit crop yield. If increased funding and education of the environmental and economic benefits of regenerative agriculture techniques are made available to farmers, there may be hope for soil salvation yet.
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