Schnitzer, Morris Land Resource Research Centre, Central Experimental Farm, Ottawa, Ontario, Canada.
Martin, James P. Department of Soils and Plant Nutrition, College of Biological and Agricultural Sciences, University of California, Riverside, California.
- Analytical characteristics
- Analysis of chemical structure
- Molecular structure
- Chemical reactions
- Functions and uses
- Biochemistry of Humus Formation
- Plant residues
- Biodegradable substances
- Polysaccharides, proteins, and lipids
- Humic acid formation
- Polysaccharide fraction
- Links to Primary Literature
- Additional Readings
A group of substances that are natural products of earth surface environments. Probably the most widely distributed organic carbon–containing materials in terrestrial and aquatic environments, they are dark-colored, predominantly aromatic, acidic, hydrophilic, molecularly flexible polyelectrolytes. Humic substances constitute 70–80% of the organic matter in inorganic soils and are formed from the chemical and biological degradation of plant and animal residues and from synthetic activities of micro-organisms.
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