The dependence of the optical parameters of saline soils of Daghestan on the content of humic substances has been studied. There is a direct correlation between the fluorescence intensity of soils and the content of soil humus. High sensitivity of the method of optical sensing soils from the point of view of differentiation of organic carbon determines advantage of this method over others which sensitivity is constant and, at small differences in the content of humic acids, may be insufficient to detect organic substance in soils. Considering the fluorescence parameters as the state of the soil, it is possible to evaluate and predict stadial changes in soil-plant systems under external influences of environmental factors at early stages in the conditions of soil cover evolution under the influence of climatic warming.