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EN
Field surveys for aquatic plants, invertebrates and vertebrates along the banks of Kiełpińskie Lake and sourrounding oxbows were conducted in June – August 2010. The study area is located in the Vistula River valley near Warsaw in central Poland. The results document the richness of flora and fauna species in the J. Kielpińskie reserve and adjacent aquatic habitats. A large number of protected species of plants and vertebrates was recorded in the area, including amphibians, birds and mammals that are of particular importance to the European community, such as the fire-bellied toad, little bittern, western marsh harrier, beaver and otter. Among aquatic plant communities, the community of "water lilies" Nupharo-Nymphaeetum was distinguished as the most valuable. The chain of oxbow lakes connected by a small stream forms an important ecological corridor. The presence of protected species and rare plant communities associated with the aquatic environment requires a responsible approach to the conservation of these habitats, located in close proximity to a large urban area. It also requires a holistic approach to nature protection in the reserve. In this case, not only should Kiełpińskie Lake be protected, but also its surroundings, which form elements of an ecological corridor.
EN
Species diversity of gastrotrich communities on elodeids and in bottom sediments of lakes of different trophic status was compared. Thirty-eight species of Gastrotricha (34 in bottom sediment and 21 on elodeids) were found, which belong to the only family of Chaetonotidae Zelinka, 1889. Species diversity of both habitats was reflected in the diversity indices ranging from 2.02 (a dystrophic lake) to 2.67 (a strongly eutrophic lake) for bottom sediment, and from 2.01 (a mesotrophic lake) to 2.54 (a strongly eutrophic lake) for elodeids. The similarity of gastrotrich fauna from the two habitats was low, and varied from 17% (a mesotrophic lake) to 38% (a strongly eutrophic lake). Low similarity of elodeid fauna from lakes of different trophic status was also found, in spite of similar plant species composition. The lowest similarity in elodeid fauna (23%) was recorded for dystrophic and mesotrophic lakes, whereas the highest one (68%) was observed for eutrophic and strongly eutrophic lakes. That allows to conclude that the diversity of epiphytic fauna is affected by trophic status rather than by vegetation type. The comparison of the gastrotrich fauna from elodeids and bottom sediments in lakes of different trophic status provides additional autoecological characteristics of Heterolepidoderma ocellatum (Mečnikow, 1865) and allows to recognize this species as belonging to a group of species closely related to macrophytes.
EN
Bryozoans are widely distributed benthic invertebrates which form colonies both in running and stagnant waters. There are 19 freshwater species of Bryozoa in Europe, and only three have been recorded in Serbia so far. Statoblasts (the dormant stages of these colonial animals) are relatively frequently found in the gut contents of fish, but those of the Hyalinella punctata species (Phylactolaemata) have not been registered. Statoblasts of H. punctata were determined for the first time in the gut content of chub Leuciscus cephalus sampled from the Zapadna Morava River (West Serbia, Danube River basin) in late summer and autumn. The intactness in form supports their viability after the passage through intestines, implying that the fish may be a vector of the dispersal of H. punctata in new aquatic habitats, as well as a risk factor in the transmission of certain salmonid fish disease agents into fish farms and natural habitats.
EN
The relationships of Hildenbrandia rivularis (Rhodophyta), the species composition of its surroundings detailed environmental variables (water chemistry and hydrological, morphological and bottom features) in a lowland river (Wełna river, Western Poland) was investigated. H. rivularis from 40 stands was tested together with 25 environmental variables and vegetation. Detrended correspondence analysis (DCA) and redundancy analysis (RDA) were used to describe the relations between the species composition and the selected variables. The uniqueness of this protected species is an ability of formation incrustation on rocks but also coexistence with two groups of species: other algae and vascular plants. In study twenty-two plant taxa were recorded in 40 vegetation plots, including 4 macroscopic algae, 2 mosses and 16 vascular plants. The most common H. rivularis co-occurred with Leptodictyum riparium, Fontinalis antipyretica and Nuphar lutea. Most of the studied plots with red algae were characterised by shallow water and strong water velocity. H. rivularis prefers alkaline water with high conductivity. The results of the RDA, after forward selection, demonstrated that pH gradient, optical features such as dissolved organic matter and water colour – control the variation in the floristic communities with H. rivularis.
EN
In 1992 and 1993 six freshwater species formed 96% of the assemblage. In number Acanthobrama marmid Heckel was dominant (70.8%), while Liza abu Heckel, Aphanius dispar (Ruppell), Alburnus mossulensis Heckel, Barbus luteus (Heckel), and Garra rufa (Heckel) constituted 7.5, 5.2, 4.4, 4.3, and 4.1% respectively of the total fish captured. Seven marine species constituted 2.1% of this assemblage.
PL
Sześć gatunków ryb słodkowodnych stanowiło 96% zbiorowiska w 1992 i 1993 roku. Zespół był zdominowany przez Acanthobrama marmid Heckel (70.8% wszystkich złowionych ryb). Udział pozostałych dominantów (Liza abu Heckel, Aphanius dispar (Ruppell), Alburnus mossulensis Heckel, Barbus luteus (Heckel) i Garra rufa (Heckel)) wynosił odpowiednio 7.5, 5.2, 4.4, 4.3 i 4.1%. Siedem gatunków morskich stanowiło 2.1% zbiorowiska.
EN
Background. Thirty species were previously recorded for unstructured habitats (unvegetated soft substrates: USS) in Pantanos de Centla. However, a lack of information on the tropical ichthyofauna of the structured habitats such as marginal vegetation (MV), submerged macrophytes (SM) and coarse woody debris (CWD) emphasizes the importance of the aim of this paper that is the updating the records of the species distributed in these habitats, as they have been frequently reported as high biodiversity sites that are currently threatened by anthropogenic activities. Materials and methods. Sampling was carried out in 30 shallow sites, each with unstructured habitats and the three structured habitats, in Pantanos de Centla, a Ramsar wetland, over a period of three years. Fish were collected with a dip net, a drop net and a Renfro beam net. Results. A total of 6506 fish of 37 genera and 44 species were collected. Eleven species are new records for Pantanos de Centla, and the scientific name of 11 species was updated. The Poeciliidae and Cichlidae families are dominant with 10 and 13 species, respectively. Nine species of the genus Cichlasoma sensu lato were placed in six genera. Three species are new records for the Usumacinta Province. Ctenogobius claytoni, Gobionellus oceanicus, and Rhamdia quelen proved to be synonyms. Of all species, 84% were collected from USS, however, the number of species distributed in USS, MV, and SM was similar (CCj 0.4736-0.5813). Conclusion. Most of the species that were added to the previously recorded species list of Pantanos de Centla, inhabit structured habitats. This confirms the importance of including these habitats in surveys aimed at generating checklists, and of analysing the distribution of fish species in shallow tropical ecosystems.
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