Inspired by survey comments at the extension event, Vijesh Maharjan, associate professor and extension specialist at the University of Nebraska-Lincoln Panhandle Research, Extension and Education Center, conceptualized the soil health cycle (SHC) as a repetitive soil health management cycle to achieve agricultural sustainability.
“The term 'soil health cycle' was shared by an attendee at the 2023 Nebraska Soil Health School event held at the University of Newfoundland and Labrador's Haskell Agricultural Research Institute in Concord, Nebraska,” Maharjan said. “It had been mentioned in anonymous survey comments but with no further explanation. Intrigued, I searched online and found a brief mention on the Corteva Agriscience website. This prompted me to work with my co-authors to further develop the concept, which led to the now published manuscript.”
The soil health cycle is a feedback cycle in soil health management, consisting of a series of interdependent entities and steps. It includes the human aspect of making decisions about agricultural practices, their impact assessment, and reasoning to iteratively improve soil health through an iterative process that takes into account site-specific resource constraints and complex agro-ecosystems. In contrast to soil nutrient cycles, where specific nutrients, their transformations, stages, and transport pathways through soil, plants, microbes, and the environment are investigated, SHC is more similar to management cycles such as the plan-do-study-improve (PDSA) cycle, which provides a structure for iterative testing of changes to improve the quality of the system.
The SHC provides a systematic approach to integrating soil health management practices and measures soil health benefits from soil health management in terms of productivity, profitability, environmental benefits, and their cumulative impacts on policies, economic drivers, and human dimensions, completing the cycle. The cycle consists of four interdependent components: (a) human dimensions, (b) agricultural practices, (c) soil health, and (d) ecosystem services and economic benefits.
“In essence, integrated soil health management involves several interdependent components, each important to achieving agricultural sustainability,” Maharjan said. “It becomes an iterative process over time.”
“In addition to presenting and justifying the feedback cycle in soil health management to iteratively improve soil health, we also reviewed the scientific literature to determine the current state of research on the impact of soil health management practices on soil health indicators (SHI) and soil function outcomes, which are key components of the feedback cycle,” Maharjan added.
Over the past two decades, the soil health literature has grown. Evaluating the impact of soil health improvement efforts on SHI is a preliminary step to facilitating the adoption of soil health improvement efforts. Confidence in the causal relevance of improved SHI can be increased by explicitly linking SHI to soil functions such as productivity, sustainability, and profitability. Such presentations will inform policies, incentive programs, and initiatives that influence the human aspects of adopting and sustaining soil health improvement efforts. Thus, in addition to reporting on SHI, soil health experiments and reports should include one or more of the benefits of soil functions, specifically crop productivity (for food security), environmental quality and stewardship (for climate adaptation and mitigation), and economics (for farm profitability and social equity).
Such an extensive database also makes it possible to separate confounding factors and present and contextually recommend soil health practices. The SHC encompasses all interdependent elements and steps in soil health management and recognizes the inherent challenges in promoting and sustaining soil health practices. It particularly highlights the need to bridge gaps in the relationships between practices, SHI, and soil function benefits.
