Systematic features in the study of humic substances in natural surface waters

The article has considered systematic approaches to the investigation of humus substances of natural surface water. It has been shown that the use of chromatographic methods for extraction humic matter from water and investigation of their molecular-weight distribution is accompanied by losses of these compounds owing to phenomena of irreversible adsorption. The comparative assessment of the methods of determining concentration of humus mater, in particular, spectrophotometry and fluorescent spectroscopy as well as methods based on the results of determination of water color and reaction of azo-combination using diazotized 4-nitroaniline has been made.