Soil is full of life. In the top 10cm of soil, where the majority of this life exists, you’ll find macrofauna like earthworms, mesofauna like mites, microfauna like nematodes and protozoa that feed on organic matter, and millions of bacteria and fungi. This top-most layer of soil drives production in agriculture systems; a healthy, biologically active soil is a productive soil. So, keeping soil alive and protecting soil biodiversity is an appropriate theme for the 2020 World Soil Day because global soil health, like many other ecosystems, is on a decline.
Soil organic matter (SOM), which contains about 58% soil organic carbon, and soil biology are inextricably linked because SOM is the food source for soil organisms. It often starts with earthworms, mighty ecosystem engineers that break down plant litter and transform it into useable forms by other, smaller soil microorganisms that rely on enzyme action to further breakdown the material. Through these processes of decomposition, plant litter is transformed from its recognizable form into smaller and smaller fractions that eventually are rendered into a state that the nutrients contained within them can be taken up again by growing plants. In addition to regulating nutrient cycling, soil organisms also improve soil structure and affect drainage and aeration, form symbiotic relationships with plant roots in order to pull nitrogen from the atmosphere into a form that plants can use, and play a vital role in carbon cycling and storage. It’s for all these reasons that our agriculture systems need the life in the soil in order to be productive and profitable. There are a number of practices that farmers use to support, improve, and protect soil organisms.
Increasing organic matter: whether its manure, compost, mulch, or plant residues, adding more organic matter additions to the field (and removing less plant biomass when possible) results in a larger, more diverse microbial population.
Cover crops: having a living root in the ground for more days in the year, controlling topsoil erosion, regulating soil moisture, and reducing extreme temperature fluctuations all lead to more diverse and healthy microbial communities in soil.
Increasing crop rotation diversity: adding in additional crops to a rotation, especially legume and brassica crops, help to break disease cycles and increase the diversity of organic residues that are used by soil microbes.
Reducing soil disturbance: moving away from intensive tillage towards conservation tillage or no-till systems means soil aggregates and structure can be maintained and habitat for soil organisms is protected.
Nutrient stewardship: calculating the appropriate amount of nutrients required for plant growth before applying fertilizers can compliment nitrogen cycling from organic matter decomposition and enhance phosphorus uptake through AM fungi symbiosis.
While not an exhaustive list, these five practices, when incorporated correctly, can enhance the soil ecosystem and build life in the soil. While many farmers employ these types of practices already, they only represent a fraction of our entire agricultural system. Getting more farmers to adopt these types of practices is crucial if we are to keep soil alive and protect soil biodiversity. But we can’t ask or expect farmers to start incorporating more of these practices on their own. They face financial, technical, and social barriers along the way and need support.
At PUR Projet we’ve seen a number of ways companies can support farmers in their supply chains to implement these types of practices. From setting up a fund that provides grants to farmers to purchase materials and supplies that allow them to implement soil health practices; to in-field training on Good Agricultural Practices for small holder farmers organized at the cooperative level; and innovative incentive programs that reward farmers for the outcomes achieved (and measured) after the implementation of soil health practices. These approaches ease the burden on farmers and create beneficial long-term outcomes for soil health while improving supply chain resiliency. Brands that work directly with their farmers have a massive opportunity for impact. If you’re looking for more ways to support farmers in your supply chain and have the agricultural goods in your products promote living soils, get in touch with us.
Paul is an adaptive manager, problem solver, and soil expert with a strong understanding of carbon dynamics and sequestration potential under various agricultural management practices. After earning his MSc in Soil Science, Paul joined PUR Projet as Project Manager and lead on Regenerative Agriculture topics, where he develops, implements, manages and monitors ecosystem restoration projects in agricultural landscapes across North America.