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3 The Utility and Futility of Soil Health Assessment
John F. Obrycki and Lumarie Pérez‐Guzmán
Chapter Overview
Documenting benefits from soil health management practices and assessments has been described as both useful and futile because it requires continual observation, some form of data collection, and an assessment protocol. This chapter focuses on the benefits of soil health being evaluated through soil physical, chemical, and biological property measurements. A producer, landowner, or researcher interested in soil health usually wants to know if soil properties are changing from an identifiable condition or point of interest, such as an inherent baseline or an equilibrium condition established by business‐as‐usual soil and crop management practices. When soils are considered within social, political, economic, and environmental contexts, the type of benefits that can be documented expands (Heller and Keoleian, 2003; McBratney et al., 2014; Mena Mesa et al., 2014; Rasul and Thapa, 2004; Steffan et al., 2017; Wolde et al., 2016), but although those assessment scales are important to consider, they are outside the scope of this chapter because such changes, whether positive or negative, generally take several years (perhaps even decades) to be noticeable and/or measurable. This chapter focuses on agricultural research and discusses the general opportunities and limitations associated with soil health management approaches and strategies used to document potential soil physical, chemical, and biological property changes.
Introduction
There are several important questions associated with soil health research (Fig. 3.1). These include issues associated with more clearly defining the soil health concept, determining how to measure and quantify soil health at multiple scales, and using these principles to guide current and future soil and crop management decisions. As discussed in Chapter 2, questions regarding how to achieve effective soil management are not new (e.g., Bennett and Chapline, 1928; Hobbs, 2007; Janvier et al., 2007; Janzen, 2001; Karlen et al., 1997; Karlen et al., 2019; Magdoff and van Es, 2009; Stoll, 2003). Furthermore, several visual, in‐field, and laboratory methods for evaluating soil health have been developed over several decades. Answers to those questions are not simple because the living and dynamic nature of soils results in fiscal, human resource, intellectual, and other research constraints associated with sampling, analyzing, and interpreting how soil biological, chemical, and physical properties