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.

During a midwinter cruise north of 80oN to Rijpfjorden, Svalbard, the composition and vertical distribution of the zooplankton community were studied using two different samplers 1) a vertically hauled multiple plankton sampler (MPS; mouth area 0.25 m2, mesh size 200 μm) and 2) a horizontally towed Methot Isaacs Kidd trawl (MIK; mouth area 3.14 m2, mesh size 1500 μm). Our results revealed substantially higher species diversity (49 taxa) than if a single sampler (MPS: 38 taxa, MIK: 28) had been used. The youngest stage present (CIII) of Calanus spp. (including C. finmarchicus and C. glacialis) was sampled exclusively by the MPS, and the frequency of CIV copepodites in MPS was double that than in MIK samples. In contrast, catches of the CV-CVI copepodites of Calanus spp. were substantially higher in the MIK samples (3-fold and 5-fold higher for adult males and females, respectively). The MIK sampling clearly showed that the highest abundances of all three Thysanoessa spp. were in the upper layers, although there was a tendency for the larger-sized euphausiids to occur deeper. Consistent patterns for the vertical distributions of the large zooplankters (e.g. ctenophores, euphausiids) collected by the MPS and MIK samplers provided more complete data on their abundances and sizes than obtained by the single net. Possible mechanisms contributing to the observed patterns of distribution, e.g. high abundances of both Calanus spp. and their predators (ctenophores and chaetognaths) in the upper water layers during midwinter are discussed.

Seabirds constitute an important link between marine and terrestrial ecosystems, one of its manifestations being the transport of organic matter from the sea to breeding grounds. The main aim of our study was to determine the impact of gregarious and planktivorous little auks on the quantity and chemistry of soil organic matter along the western coast of Spitsbergen, Svalbard archipelago. Samples from the vicinity of four breeding colonies and respective controls were investigated using the elemental analyzers as well as the Fourier transform infrared spectrometer with attenuated total reflection module. The results clearly indicate that soils affected by little auks are characterized by significantly higher content of soil organic carbon, total nitrogen, water-extractable organic carbon, and water-extractable total nitrogen in comparison with those unaffected by the birds. The size of the local population of little auks appears to be the crucial factor here. The chemistry of soil organic matter in soils affected by little auks is significantly different from that in soils unaffected by the birds. This is associated with fertilization of soils via guano deposition as well as differences in the quantity and quality of vegetation cover related to aforementioned process.