Solar radiation reflectance was analysed to characterize Arctic ornithogenic tundra developing in the vicinity of large breeding colony of Brunnich‘s guillemots Uria lomvia and kittiwakes Rissa tridactyla at the foot of Gnĺlberget cliff (Hornsund, SW Spitsbergen). Radiometric method was found to be a useful tool for studying structure and functioning of plant formations. We measured reflectance of four wavelengths: 554 nm (YG), 655 nm (RED), 870 nm (NIR) and 1650 nm (SWIR) at 10 plots situated along the transect running from the colony to the sea. Moreover, data of plant community character, species quantitative composition as well as total biomass were collected to relate these parameters with the spectral values. The results showed that radiometric data characterized vegetation well enough to recognize the same plant communities on the basis of spectral reflectance as distinguished with traditional phytosociological methods.