Fundamentals of soil characterization

The characterization of soil properties is essential in determining a soil's optimal use and changes to the soil over time. Furthermore, soil properties often serve as differentia which inform soil taxonomic classification systems. Rudimentary soil analysis began over a century ago. In the decades that followed, technological advancements led to new laboratory and field-based soil testing capabilities. This chapter reviews several of the most common fundamental soil analyses. Included in this review are soil physical properties (e.g., texture, bulk/particle density, compaction, soil solution/infiltration/percolation, mineralogy), soil chemical properties (e.g., pH, salinity, organic matter/organic carbon, cation exchange capacity), and soil biological properties (e.g., microbial communities, organic matter pools, enzymes, respiration). Additionally, field-based methods are reviewed in support of soil morphological description and sampling. Both the theory and simplified quantitative methods are presented herein, especially as a precursor to sensor-based soil characterization provided in Chapter 3.