Saccharides

Abstract

Almost 200 polysaccharides are now known to occur naturally. It is probable that the majority are at some time added to the soil. They do not, however, remain in the soil indefinitely, but are attacked by the soil fauna and flora, which in turn will contribute other saccharides to the soil. The nature of polysaccharides in soils must, therefore, be deduced in part from the known properties of the polysaccharides added to the soil and produced in it and, in part, from a knowledge of the saccharides that can be isolated from the soil itself. As yet, the techniques for the isolation of saccharides and polysaccharides from soils are very inadequate. This isolation is difficult largely because of the strong interaction between the inorganic materials and much of the saccharide fraction of soil organic matter. To date, little more than half of the carbohydrates known to occur in the soil have been separated from the inorganic materials. In this review the major groups of saccharides added to the soil are described first (Table 1), and the factors involved in their decomposition in the soil are discussed. Then the amounts of polysaccharides found in soils, their isolation from soils, and the properties of the isolates are considered. Finally, a brief account of the relationship between saccharides in the soil and other soil properties is presented.