Earthworms for Soil Organic Matter Mineralization and Carbon Sequestration

Earthworms are known to modify soil structure and alter the physicochemical and biological regimes of soils. Both laboratory and field experiments confirmed the effects of earthworms on soil characteristics, which may be physical, chemical, biological, or a combination of all three. Earthworms through their vital activities such as feeding, burrowing, and casting play important roles in the transformations of primary and secondary minerals and nutrients to available and accessible forms for plants and soil microorganisms and thus increase soil fertility and quality. Many challenges remain in determining the operational role of earthworms in Soil organic matter (SOM) dynamics, carbon sequestration, and aggregate formation. After moving through the stomachs of earthworms, soil particles are entirely rearranged and form aggregates, and consequently, contribute to mineral weathering and SOM formation. Earthworms partially decompose SOM, whereas a portion of it is physically protected within microaggregates. Complementary studies are needed to assess the impact of earthworms on SOM dynamics, the conditions under which physical protection develops, and the impact of earthworms on microbial community structure.