ИСТИНА

Commercial humic products (HPs) from various resources are being increasingly used in agriculture and environmental technologies. The key factor influencing their chemical properties and biological activity is the organic matter genesis. The objective was to determine indicators using chemical and spectral proxies that might serve as tools to compare HPs from various environments, as bulk materials and their HA fractions. HA fractions were isolated from commercially available humates industrially manufactured from different source materials (lignite, peat, lake bottom sediment, lignin); and analyzed using chemical, fluorescence and UV-vis measurements. Among chemical properties content of N and IR-spectra were the most descriptive parameters. Information extracted from absorption and fluorescence spectra can be useful to discriminate organic matter source for HPs from coalified materials, peat and lignosulphobate. Indexes with the highest descriptive ability are specific absorbance SUVA254, absorbance ratios E 270/400, E 280/472, derivative indices FDR280/240 and SDR267/280, wavelength of fluorescence maximum and the presence of “blue shift”.