ИСТИНА

Soil matrix and plant nutrition. The Maximum quantity of nutritious elements in soil is concentrated in solid particles, and accessible to plants - in a soil solution. However the soil solution does not exist in itself, in dry soil it even is not present. It is result of interaction of atmospheric precipitations with a soil matrix. As morphology the soil matrix represents a superficial layer of solid soil particles. Its functioning is shown in the organization particles, molecules, ions around of itself in the certain order. The matrix is characterized by geometrical, chemical and power heterogeneity. The most active elements on it are the active centers. They take up very insignificant part of all surface (0,1-20 %), and define almost all its reactionary ability and orientation of substances around of it, and also formation of an absorbed layer. The matrix is characterized by quantity and force of the active centers. Their number, as a rule, is proportional to the general surface, but the factor of proportionality can be distinguished in different soils and horizons. Chernozems have many "very weak" and "weak" acid centers on which nutritious elements are kept. Soddy-podzolic soils are characterized by rather raised maintenance of the "strong" acid centers. The matrix together with an absorptive layer keeps nutritious elements with different force. A part from them can pass in a solution and be absorbed by roots of plants.