Lessons from Econometric Theory to Develop Novel Indication Systems for Soil Quality, Soil Health and Soil Security.

Soil scientists have worked on the conceptualization and contextualization of soil related notions, such as soil quality, soil health, and soil security over a few decades. Our literature review showed that all three major soil concepts are still primitive and lack quantification. Yet quantification is critically important to compare, assess and monitor soils across different regions and time with multiple scales and synthesize them into larger frameworks. Since there are multiple and interacting functions of soils the challenge is to identify observable properties that allow depicting losses/gains of functionality. This is profoundly difficult in soils where functions depend on soil genesis operating over long time frames where “natural” reference conditions of soils are unknown. However, if they are not quantified and formalized coherently as to how to assess soil quality, soil health, and soil security, they remain shallow buzz words. To maintain/enhance the quality and quantity of soil resources inherently requires contextualization to human preferences and beliefs and values people hold. A new soil indication system that is universally applicable in different geographic multi-use, multi-function soilscapes undergoing change is urgently needed. Thus, we recognize the need for integral, yet feasible and meaningful quantification schemes, such as indicators (In) / indices (Ix).

The literature review revealed that (i) there is a lack in harmonization, standardization and reference frameworks that would allow comparisons across regions and time, (ii) inappropriate adoption of methods to calculate In/Ix (e.g., inappropriate methods, such as ordination and factor analysis, have been employed to calculate In/Ix), and (iii) many In/Ix studies in soil/environmental sciences do not meet rigorous axiomatic criteria of scientific sound indication systems. We identified several econometrical methods with the potential to be applied to assess the quality and quantity of soils that overcome the shortcomings outlined in the review of past and contemporary In/Ix studies.