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EN
The buoyant hypopycnal flow of brackish water and suspended sediment transport and settling were studied in two sub-polar fjords: the glacial Kongsfjorden and the outwash (non-glacial contact) Adventfjorden, Svalbard. The data presented indicates faster water mixing on the tidal flat in comparison to the englacial runoff, which leads to faster horizontal density gradients decreases in the non-glaciated fjord. The fast settling of particles in the narrow zone of the steep slope at the edge of the tidal flat leads to the removal of 25% of the surface suspended sediment. The rapid settling is due to increasing salinity, decreasing velocity, and flocculation of fine particles. The fast settling of suspended particulate matter (SPM) in the tidal flat area causes sediment redeposition and resuspension followed by sediment transport along the bottom with hyperpycnal flows. This leads to grain sorting in the fjord head. In contrast, at the glacier front, SPM is transported farther into the fjord, where tidal pumping and water mixing lead to the removal of 71% of total SPM. The fjords investigated represent two different sedimentological regimes. In the glaciated Kongsfjorden, the buoyant hypopycnal flow of brackish water is the main sediment transporting factor. In the non-glacial Adventfjorden, hyperpycnal flows transport sediment along the bottom.
EN
The hydrological conditions, suspended matter concentrations and vertical par- ticulate matter flux were measured as the River Vistula flood wave (maximum discharge) was flowing into the southern part of the Gulf of Gdańsk on 26 May 2010. Extending offshore for several tens of kilometres, the river plume was well stratified, with the upper layer flowing away from the shore and the near-bottom water coastwards.
EN
The shallow water benthic fauna was collected in Kongsfjord, West Spitsbergen. Sampling was conducted along two main environmental gradients: vertical gradient (depth 5-50 m) and horizontal gradient (sedimentation regime) along the fjord axis. A small rectangular dredge was used. Altogether 169 taxa were identified and four macrofaunal associations were distinguished. Bottom type and distance from the tidal glaciers seem to be the main factors responsible for species distribution. The Soft Bottom I Association occupying the fine mud of the Kongsbreen glacial bay consisted mostly of Crustacea with high dominance of scavenging amphipod Onisimus caricus. Bivalves prevailed in the Soft Bottom II Association, located further away from the main glacier outflows. The barren rocky shelf, deprived of vegetation by a sea urchin Strongylocentrotus droebachiensis was inhabited by the Rocky Shelf Association dominated by decapods. The last distinguished association (the Kelp Association) occurred on the hard bottom overgrown with macroalgae. The gastropod Margarites helicinus and amphipods Ischyrocerus spp. made up 60% of the individuals collected there.
EN
Recent sediment accumulation rates in Adventfjorden (Svalbard), a small subpolar fjord, were determined by 210Pb and 137Cs dating. Modern rates in the central basin decrease downfjord from 1.87 to 0.87 cm y−1 (2.6 to 1.19 g cm−2 y−1). Comparison of the modern values (1986–2001) with older ones (1963–86) reveals a marked increase in sediment accumulation rates in the last ten years. This correlates well with recent climate changes (warming and increase in precipitation). Comparison with particulate matter flux data indicates that a portion of the sediment is passed on to Isfjorden.
EN
The septomarginal trabecula is present in all human hearts as well as in the hearts of other primates. It usually connects the interventricular septum with the anterior papillary muscle, although there are many variations in how this is achieved. The object of the analyses was to estimate the bilateral topography of the septomarginal trabecula and the anterior papillary muscle in the context of the ontogeny and phylogeny of primates. A total of 138 hearts were examined from number of different non-human primates. The presence of the septomarginal trabecula was confirmed in 94.9% of cases, although not in the hearts of Lemur varius. Four configurations could be distinguished by defining the location of the septomarginal trabecula and its relation to the anterior papillary muscle. For the hearts of the Strepsirrhini and the majority of Platyrrhini neither structure was related, whereas in all examined representatives of Hominoidea they had fused and created morphologically varying forms. On the basis of these results, a concept was developed for the sequence of changes which the topography of the septomarginal trabecula and the anterior papillary muscle undergo during ontogeny and phylogeny. (Folia Morphol 2013; 72; 3: 202–209)
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