Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Felipe G. Sanchez
    Date: 1998
    Source: The Productivity & Sustainability of Southern Forest Ecosystems in a Changing Environment Edited by Mickler & Fox
    Publication Series: Miscellaneous Publication
    PDF: View PDF  (148 KB)


    Soil-organic matter (SOM) is a complex array of components including soil fauna and flora at different stages of decomposition (Berg et al., 1982). Its concentration in soils can vary from 0.5% in mineral soils to almost 100% in peat soils (Brady, 1974). Organic matter (OM) in the surface mineral soil is considered a major determinant of forest ecosystem productivity because it affects water retention, soil structure, and nutrient cycling (Powers et al., 1990; Paul 1991). Soil-organic matter is the major source of nitrogen available to plants and contains as much as 65% of the total soil phosphorus (Bauer and Black, 1994). During decomposition, OM is broken down into various components including carbohydrates, amino acids, proteins, nucleic acids, lipids, tannins, lignin, and humus. Humus refers to the microbial resistant forms of SOM that remain after major portions of added plant and animal residues have decomposed. Its chemical nature has not been completely determined but it is believed to consist of various polymeric compounds, probably aromatic and aliphatic in composition (Schnitzer and Schulten, 1992). Humus has been found to affect the physical properties of soil (Elliot, 1986; Beare et al., 1994). Thenonhumuscomponents of SOM are crucial in nutrient cycling dynamics and are the primary source of food and energy for soil microorganisms (Cambardella and Elliot, 1992; Wander et al., 1994). As such, these components are the driving force for productivity.

    Publication Notes

    • You may send email to to request a hard copy of this publication.
    • (Please specify exactly which publication you are requesting and your mailing address.)
    • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.


    Sanchez, Felipe G. 1998. Soil Organic Matter and Soil Productivity: Searching for the Missing Link. The Productivity & Sustainability of Southern Forest Ecosystems in a Changing Environment Edited by Mickler & Fox

    Related Search

    XML: View XML
Show More
Show Fewer
Jump to Top of Page