Life above ground depends on the soil and its countless inhabitants. Yet, global strategies to protect biodiversity have so far paid little attention to this habitat.
Soil biodiversity drives the carbon, nitrogen and water cycles. The microflora and fauna present in the soil provide nutrients, decompose organic matter and solidify soil structure which is very critical for activities like agriculture among others. Without soil organisms, no plants would be able to grow and no humans could live.
Quick Fact: A handful of garden soil can contain thousands of species, millions of individuals and over a hundred metres of fungal network.
However, healthy soils are becoming increasingly rare. When land is degraded, it loses its soil biodiversity causing land to produce less food, store less water and release carbon into the atmosphere. The top factors that deplete soil health are salination (poisoning caused by excessive saltwater getting absorbed into soil), erosion (when the top layer of the soil is removed by wind action), compaction (caused by heavy machinery that squeezes the air out of the soil threatening the habitats of the organisms) and sealing (when access to the surface is sealed off by concrete as a result of urbanisation).
Agriculture is both a boon and a bane for underground biodiversity. While certain activities like mulching (covering soil with protective layer of compost) and the use of good quality and organic manure can significantly improve the quality of soil, intensive use of synthetic pesticides and fertilisers can alter the pH balance and lead to certain organisms dying out. Farmers also a play key role here by way of cropping decisions and use of farming machinery. While certain machines improve soil health through cyclical rotation, others can result in compaction. Cropping decisions should be made while keeping the type of soil in mind and not doing so can lead to destroying the local biodiversity and loss of produce as well.
Over the past 50 years the total food production increased 2.5 – 3 times due to advancements in modern agricultural practices but since this was not backed by extensive research conducted on soil biodiversity, the impending impact of this will be borne by future generations. Some of the after effects that are visibly apparent now include poor quality of groundwater, reduction in quality of consumable crops due to lack of fertile soil and unanticipated climatic changes – soil sequesters carbon from the atmosphere and reduces greenhouse gas emissions, the loss of its ability to act as a deposit increases emissions and can accelerate climate change.
It is important that we adopt farming practices that increase soil biodiversity including sustainably managing soil water and nutrients, controlling erosion, and maintaining groundcover. One such method is agroforestry, which involves planting trees alongside crops.
A major initiative Soil BON is underway, to gather, study and monitor soil across the globe, sharing information needed to ensure living soil resources are sustainably conserved and managed and can support essential human needs.
Who would’ve thought this universe that exists under our feet holds the key to a multitude of problems? With a little conscious effort, soil health can be improved considerably. All it needs is to be included in the policies and actions that are being implemented but backed by solid research.