Soil Health and Food Security
An oft-mentioned aspect of production sustainability/food security is soil health, which is defined by the USDA-NRCS (click here) as “the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans”. They further state that “this definition speaks to the importance of managing soils so they are sustainable for future generations”. It goes without saying that soil health has been and will continue to be tied to food security–i.e. if soil health is degraded, then food production will decline.
Understanding soil health involves assessing and managing a soil’s inherent properties of fertility, structure, microbial activity, etc. so that it functions to support optimal plant growth and yield, both now and in the future. This means that changes in soil health must be constantly assessed to determine if a current production system is in fact positively or negatively affecting known soil health components. Click here for a White Paper on this website that provides a detailed discussion of soil health.
It is well-known that the vast majority of food is produced on soils, and these same soils also contribute to the production of crops for biofuel and fiber. Soils also provide an ecosystem that is habitat for living organisms that are vital components of the soil environment, as well as other ecosystem services such as water filtration and carbon storage. Thus, there is no doubt that healthy and productive soils are vital for ensuring that food production continues to be secure.
A recent (June 2021) article titled “Soil health considerations for global food security” by Bagnall et al. appears in Agron. J. (https://doi.org/10.1002/agj2.20783). The focus of the paper is to present the relationship between soil health and global food security, with a focus on the role that farmer profitability plays in soil health maintenance. Major points taken from the paper follow.
• Specific objectives of the research described in the paper were to: 1) consider the role that U.S. agricultural production plays in global food security; 2) consider key mechanisms by which soil health impacts U.S. agricultural production; and 3) offer a comprehensive strategy to foster adoption of soil health systems on a wide scale.
• The U.S. typically ranks in the top three countries for food security. This is primarily due to the country’s soil resources, climate that is conducive to crop production, and science-based innovations (i.e. plant improvements resulting from crop breeding and biotechnology tools) that have been developed and adopted by U.S. farmers.
• Global population continues to increase while available arable land and water resources for food production continue to decline or are at risk of being diverted from agriculture.
• If the necessary increase in U.S. food production does not occur with a corresponding improvement in soil health, the long-term effects will be detrimental to increased food production, and the quality of resources needed for that production. Thus, to maintain adequate food production, enhanced soil health must occur in unison.
• Soil management practices (i.e., no or limited tillage, cover crops, etc.) that contribute to enhanced soil health have been extensively tested and validated in the U.S., yet they have relatively low adoption.
• Soil health has direct effects on 1) crop yield, 2) crop yield resiliency, and 3) farmer profitability. Each of these in turn affects food security.
• Both research and farmer experience have shown the long-term positive effects of soil health management practices such as no or limited tillage on crop yield. Specific soil health management practices that are associated with increased crop yields must be positively identified and subsequently adopted on a large scale to ensure that they are used to support a continued increase in or maintenance of crop yields.
• The contribution of enhanced soil health and associated management practices toward yield resiliency or low year-to-year yield variability must be determined. This aspect of crop yield must be considered as important as increasing crop yield.
• It is an accepted fact that U.S. food production has been and continues to be a major contributor to global food security. However, for this trend to continue, 1) management practices that enhance soil health must be adopted on a large scale, and 2) any practices that are adopted or promoted to enhance soil health to subsequently increase and/or stabilize U.S. food production must be profitable. Otherwise, such practices will not be adopted on a scale large enough to ensure increased/stable food production, or farmers will simply go out of business.
Take Home Message. Food security benefits that may be achieved with enhanced soil health require that production systems that enhance soil health must become the new paradigm or standard in U.S. agriculture. The centerpiece of this strategy is that producers must decide to adopt such practices because they will increase production potential in a profitable manner. Future research and development programs in the U.S. should be focused on quantifying the benefits of enhanced soil health, such as an improved soil microbiome, increased carbon sequestration, optimized nutrient use efficiency, improved soil-plant-water relations, and farmer profitability.
Composed by Larry G. Heatherly, Aug. 2021, larryh91746@gmail.com