ABSTRACT
This chapter provides an overview of the approaches used to characterize and quantify soil organic matter storage, as reported in the literature, and to provide some examples of the most promising techniques. Assessment of total organic matter storage employ either wet or dry oxidation techniques and take into consideration the thickness and bulk density of the soil layers to express stored organic matter on a mass per unit area or equivalent mass basis. Physical separation disrupts soil aggregates and particles that contain organic matter by supplying enough energy to overcome the strength of the various binding agents or mechanisms that underly the aggregation process. Relationships between soil structure and organic matter are of current interest because soil structure, which itself is mainly formed by biological processes, exercises strong control over organic matter dynamics and storage in soil systems. In some cases, characterization of the chemical structure of the organic matter stored in different fractions or pools is of interest.
