Burrowing organisms(rodents, earthworms, ants, etc.) Continually mix soil (improve tilth) Assist in decomposition of organic matter Contribute organic matter upon death 5.4.3 Microorganisms Organic matter decomposition, humus formation Add organic acids and chelates Active in nutrient cycles Mediate Oxidation-reduction reactions 5.5.
(humus formation; Add; organic acids and chelates)
humus formation
Add
organic acids and chelates