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Notes: Kongsfjorden is a glacial fjord in the Arctic (Svalbard) that is influenced by both Atlantic and Arctic water masses and harbours a mixture of boreal and Arctic flora and fauna. Inputs from large tidal glaciers create steep environmental gradients in sedimentation and salinity along the length of this fjord. The glacial inputs cause reduced biomass and diversity in the benthic community in the inner fjord. Zooplankton suffers direct mortality from the glacial outflow and primary production is reduced because of limited light levels in the turbid, mixed inner waters. The magnitude of the glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground for marine mammals and seabirds. Even though the fjord contains some boreal fauna, the prey consumed by upper trophic levels is mainly Arctic organisms. Marine mammals constitute the largest top-predator biomass, but seabirds have the largest energy intake and also export nutrients and energy out of the marine environment. Kongsfjorden has received a lot of research attention in the recent past. The current interest in the fjord is primarily based on the fact that Kongsfjorden is particularly suitable as a site for exploring the impacts of possible climate changes, with Atlantic water influx and melting of tidal glaciers both being linked to climate variability. The pelagic ecosystem is likely to be most sensitive to the Atlantic versus Arctic influence, whereas the benthic ecosystem is more affected by long-term changes in hydrography as well as changes in glacial runoff and sedimentation. Kongsfjorden will be an important Arctic monitoring site over the coming decades and a review of the current knowledge, and a gap analysis, are therefore warranted. Important knowledge gaps include a lack of quantitative data on production, abundance of key prey species, and the role of advection on the biological communities in the fjord.

Notes: Kongsfjorden-Krossfjorden and the adjacent West Spitsbergen Shelf meet at the common mouth of the two fjord arms. This paper presents our most up-to-date information about the physical environment of this fjord system and identifies important gaps in knowledge. Particular attention is given to the steep physical gradients along the main fjord axis, as well as to seasonal environmental changes. Physical processes on different scales control the large-scale circulation and small-scale (irreversible) mixing of water and its constituents. It is shown that, in addition to the tide, run-off (glacier ablation, snowmelt, summer rainfall and ice calving) and local winds are the main driving forces acting on the upper water masses in the fjord system. The tide is dominated by the semi-diurnal component and the freshwater supply shows a marked seasonal variation pattern and also varies interannually. The wind conditions are characterized by prevailing katabatic winds, which at times are strengthened by the geostrophic wind field over Svalbard. Rotational dynamics have a considerable influence on the circulation patterns within the fjord system and give rise to a strong interaction between the fjord arms. Such dynamics are also the main reason why variations in the shelf water density field, caused by remote forces (tide and coastal winds), propagate as a Kelvin wave into the fjord system. This exchange affects mainly the intermediate and deep water, which is also affected by vertical convection processes driven by cooling of the surface and brine release during ice formation in the inner reaches of the fjord arms. Further aspects covered by this paper include the geological and geomorphological characteristics of the Kongsfjorden area, climate and meteorology, the influence of glaciers, freshwater supply, sea ice conditions, sedimentation processes as well as underwater radiation conditions. The fjord system is assumed to be vulnerable to possible climate changes, and thus is very suitable as a site for the demonstration and investigation of phenomena related to climate change.

Notes: Seasonal variations and spatial distribution of suspension composition and concentration were determined in the Hornsund fjord on south Spitsbergen along with bottom sediment mineralogy and glacial-marine mud accumulation rates. These data were related to macrobenthos biomass distribution, as well as geochemical and hydrognphic data. The axial distribution of sediment accumulation rates follows exponential decay. Slopes of the seaward decay are different for individual meltwater sources in Hornsund and, in general, they are higher than in river-fed fjords. Intensity of suspension settling is enhanced by strong retardation of meltwater flow and turbulence within the shear layer of meltwater jet sliding over strongly saline water. The most intensive settling, controlling the overall efficiency of mud deposition (up to 35 cm/a) occurs in the ice-proximal jet zone of meltwater plume. It results from turbulent diffusion of dense suspension (〉1, 000 mg/1) to the underlying still-water layer. Within the more distal, slow-advection zone the sediment accumulation rate falls below 1 cm/a. Suspension is deposited here mostly due to slow settling of mature floes across the halocline. This bipartite lateral zonation results in (1) clay-mineral segregation observed in bottom mud in the ice-proximal jet zone (2M, large-flake muscovite is separated from lMd clay-grade illite), and (2) high accumulation rate and extremely rapid decay away from the source. High concentration of surface-active clays in the rapidly accumulating sediment renders the proximal mud a closed system and a physical trap for nutrients.The seasonal rhythm of changes in suspension composition reveals a time lag between maximum of organic suspension concentration and onset of clastic sedimentation. This lag along with the absolute dominance of clastic flux during summer-autumn, result in sulphidic (dark-light) lamination of ice-proximal mud. High clastic input and high surface water turbidity result in formation of a benthos-poor zone in the ice-proximal settings. There, formation and preservation of original monosulphidic lamination and scarcity of benthic life are mutually dependent. Control over these follows by damping of primary production in the photic zone and trapping of nutrients in the bottom sediment by clastic dilution and fast burial of organic material.

Notes: The copepods Limnocalanus macrurus G. O. Sars and Eucyclops serrulatus (Fisch.) and the ostracode Cytherissa lacustris (G. O. Sars), hitherto unknown on Spitsbergen, were found in Lake Rewatnet, the last species also in Lake Svartvatnet. Samples from parthenogenetic populations of C. lacustris showed a complete lack of electrophoretically detectable variability at four enzyme-encoding loci, two of which are highly variable in mainland populations. However, morphological variation in the carapace length and nodation was no less than in the mainland populations. The carapace valves of C. lacustris do not preserve well in the sediments of Rewatnet.