Soil Spectral Databases

This paper identifies and discusses two trends in the digitalization of soil research data: (1) creation and maintenance of databases containing reflectance spectra of the upper soil horizons in the range of 300–2500 nm and information on the main physicochemical properties of these horizons; and (2) accumulation and actualization of already published spectra in the visible range (400–750 nm) and incorporation of the data on all horizons constituting the soil profile into the spectral databases, which makes it possible to identify both individual horizons and entire profiles. The second trend widely uses color parameters of soils; this applies both to international optical systems and to Russian-specific indicatory systems. The algorithms used in such databases can be applied in studies involving open-access global soil libraries.