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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.
The present qualitative and quantitative study on macrozoobenthos was conducted in 1998 in the coastal zone of the Baltic Sea adjacent to the Słowinski National Park (SNP). The macrozoobenthos of this zone exhibited quantitative scarcity (12 species) and low content of the wet mass. More frequent were only Oligochaeta, Pygospio elegans, and Batyporeia pilosa. Because of a better specific diversity, density, and wet mass of the macrozoobenthos in the zone outside 1 nautical mile limit, the author suggests widening the proposed marine protected zone of the SNP giving it the status of marine Landscape Park up to 3 nautical miles.
This paper presents new findings on oligochaete species inhabiting Polish brackish waters. Identification of 455 specimens collected in September 2013 and July 2014 during the macrozoobenthos survey in the Port of Gdynia (the Gulf of Gdańsk, the southern Baltic Sea, Poland) showed the presence of six species belonging to two subfamilies Naidinae and Tubificinae.
This study presents a quantitative approach to mapping benthophagous fish feeding grounds. This approach combines the spatial biomass distribution of benthic prey items and their importance for the diets of predators. A point based biomass data of macrozoobenthos together with a set of environmental factors was used to develop Random Forests models that produce continuous biomass distribution layers for individual prey species. Depending on the diet composition and the importance of prey for fish feeding, these layers are overlaid and an integrated GIS map of the seabed showing the quality of feeding grounds is generated. These maps provide a useful basis for conservation and marine spatial planning. In addition, this method could be applied to the mapping of resources used by other benthophagous organisms. The method is presented using the example of three common Baltic fish species: cod, flounder and viviparous eelpout.
The data obtained within the framework of a survey of macrozoobenthos and fish communities in Czech streams of the Danube and Elbe river basins were evaluated with respect to the relation between biodiversity and level of water (organic pollution) and/or physical habitat quality (heterogeneity, substrate, riparian vegetation, canalisation). The diversity of macrozoobenthos species was the highest at the water quality corresponding to betamesosaprobity (saprobiological index SI ≈ 2,0) and oligosaprobity (SI ≈ 1,0) in lowland and highland streams respectively, declining both towards lower and higher saprobic (≈ trophic) levels. The response of macrozoobenthos to habitat quality deterioration was less considerable with rising degradation in highland streams than in lowland ones. Fish assemblage followed a similar trend, namely: the highest biodiversity in betamezosaprobity in both lowland and highland streams. In comparison with the assemblage of benthic macroinvertebrates, fish community response was more pronounced both regarding water quality and habitat degradation. Both fish and macrozoobenthos biodiversity were influenced more by water quality than by physical habitat degradation.
This study was designed to investigate seasonal and annual changes in the benthic macrofauna in relation to changes in hydrogen sulphide concentration in the sediment and the oxygen content in the water column. Data were collected over a three-year period from 1994 to 1997. The benthic macrofauna inhabiting the sediments of the Gulf of Gdańsk, in which H2S is permanently present, consists mostly of species with a high tolerance to oxygen deficiency and the presence of H2S. These species are: Macoma balthica, Harmothoe sarsi, Nereis diversicolor, Saduria entomon and Halicryptus spinulosus, as well as Pontoporeia femorata and Corophium volutator, which are more sensitive to these factors. In 1996–1997 a decline in the abundance of almost all benthic species, and especially of the bivalve M. balthica at all the stations was observed in comparison to 1994–1995.
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