Thinking about soil health: A conceptual framework

This paper uses a dynamic economic model to take a holistic view of what constitutes soil health. The model considers actions taken over multiple periods of time to maximize the combined value of crop production, environmental quality, and investments in soil characteristics net of the costs of those actions. The model makes it clear that how soil health is assessed depends on the set of services soils provide and on the value that society places on those services. The temporal and spatial variability of those services and their values implies that the characteristics defining healthy soils will be location-specific and time-dependent. An additional implication is that an index of soil health valid for all places and times is unlikely to be feasible, although a soil health index that is “good enough” for specific locations at specific times may well be possible. Empirical evidence indicates that choices about managing soils generally involve tradeoffs, i.e., that “win-win” actions that increase agricultural productivity, improve environmental quality, and build up stocks of desirable soil characteristics are unlikely to occur. Assessments of soil health are most productively conducted by focusing on aspects of agricultural productivity, environmental quality, and soil characteristics of primary importance while ignoring those of secondary importance. Greater interdisciplinary cooperation between economists, soil scientists, and environmental scientists is likely the most fruitful path for making progress in developing methods for measuring soil health.