humus(redirected from Humic matter)
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humusthe organic material that is derived from the breakdown of plant and animal material occurring in the surface layers of the soil. Humus is black and colloidal in nature, coating the soil particles and improving the fertility of soil in several ways:
- in acting as a reservoir of numerous nutrients which it prevents from leaching deeper into the soil layers;
- in increasing the water holding capacity of the soil and
- in improving the soil texture (friability).
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005