What is Soil Health?

June 24, 2022

Greg Clark, Field Researcher, QLF Agronomy

What is soil health?  The majority of land-grant universities’ have adopted the definition of soil health as “the continued capacity of soil to function as a vital living system, within an ecosystem and land-use boundaries, to sustain biological productivity, promote the quality of air and water environments, and maintain plant, animal and human health” [Doran and Safley, 1997].  Thirty years ago, soil valuations focused on crop production, mainly crop yield. Soil health was barely examined. However today, soil health along with soil biology are important components to agricultural soil assessments. These include the role of soil in water quality, biodiversity both above and below the surface, climate change, human health, and crop productivity.

Enumerating soil health is still dominated by certain values [e.g., chemical fertilizers], despite the growing awareness of the importance of soil biodiversity, due to limited functional knowledge and a lack of effective procedures.   Soil biodiversity and microbial activities [e.g., CO2 respiration] will be the primary focus of this article, thus highlighting the importance of its roles in agricultural sustainability by keeping essential functions in soil health that concentrates on carbon and nutrient cycling as part of the discussion.

Soil supports important ecological benefits for the nourishment and survival of life.  Soil health management is essential for the maintenance of soil biodiversity and preserving sustainable agricultural production.  The health of the soil is structured by soil properties, both biological and physical.  Today’s agriculture is dependent upon fertilizers.  Chemical fertilizer plays an indispensable role in soil fertility, crop productivity, and soil microbes.   The applications of fertilizers not only increase crop productivity but also can modify soil physicochemical and biological properties. Conversely, continuous utilization of certain chemical fertilizers is considered responsible for the decline of soil organic matter [SOM] and soil microbe colonies, thus resulting in a decrease in the quality of productive soils.

Over the past several years, QLF Agronomy field research has demonstrated that Liquid Carbon-Based Fertilizers [L-CBF] have modulated the biological soil activity as a source of carbon [C], energy, and plant nutrients within the soil system.  Research data has proven that organic carbon and immobilized minerals must be recycled in the ecosystem before being utilized by soil microbes in a continuous and sustainable life cycle. Changes in microbial respiration due to the increase of organic carbon inputs along with a moderate decrease in chemical fertilizers into the soil via surface or rhizosphere have allowed an increase in mineralization of soil elements [e.g., plant minerals and CO2], Figures 1 and 2.   However, mineralization rates have been heavily dependent on the quantity and quality of the organic material and C in the soil.

Furthermore, the observation, evaluations, and utilization of carbon-based fertilizer products have been proven to achieve better soil health.  It is imperious to keep in mind that soil microorganisms are the main agents of nutrient cycling and has a synergistic relationship with plants and the rhizosphere.  Utilizing QLF Agronomy L-CBF is a strategy that contributes to a better equilibrium of soil microorganisms [achieve with L-CBF] can result in greater crop productivity, at a modest cost, and contributes to the lessened use of mineral fertilizers, thus favoring high agricultural sustainability and soil microorganisms.





Doran, J.W.; Safley, M. 1997. Defining and assessing soil health and sustainable productivity. p. 1-28. In: Pankhurst, C.E.; Doube, B.M.; Gupta, V.V.S.R., eds. biological indicators of soil health. CAB International, Wallingford, UK.

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