Having a rich and diverse soil life is good for crops for many reasons. Biodiversity can lead to rapid and efficient cycling of nutrients, greater resilience to plant diseases, less erosion and better soil quality overall. Scientists now speculate that soil biodiversity is also linked to human health.
Soils with abundant and diverse microorganisms can produce healthier, possibly more nutritious crops for the reasons stated above. But diverse soil life can also control soil borne parasites and pathogens that cause disease in humans, such as anthrax, pinworms and Valley Fever. Also, when children are exposed to biologically active soil, they are less likely to develop asthma and allergies.
A soil with high biodiversity can cycle and retain nutrients well. This means that there will likely be less nutrient run-off, and less water pollution (particularly by nitrates). Also, many of the antibiotics currently in use are derived from soil life. Who knows what other valuable compounds may also live in the soil.
For these reasons, the authors promote farming practices that enhance biodiversity, including using diverse crop rotations, cover crops, agroforestry and conservation tillage.
Source: Soil biodiversity and human health. D. H. Wall, U. N. Nielsen, J. Six. Nature. 2015. Vol. 528. Dec. pp. 69-77.
- Janet Wallace