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Studies were carried out in 1999 and 2000 in the vicinity of Turew near Poznaƒ (West Poland) and dealt with the composition, density and biomass of soil-litter macrofauna with special reference to dipteran larvae in the agricultural landscape. Sites were located on a 7- years old mid-field shelterbelt and on adjacent field with maize crop in the first and wheat crop in the second year of study and – on 9 various patches of vegetation within the mid-field shelterbelt. Studies carried out along the transect: the shelterbelt (S) – ecotone (E) – field 10 m (F 10)– field 50 m (F 50) demonstrated a decline of: 1) animal density (10 times) and biomass (30 times) of total macrofauna and (80 times) of dipteran larvae, 2) taxonomic richness and biodiversity measured with the H` index, 3) individual weight of the entire macrofauna, of dipteran larvae, saprophagous animals and predators so that the individuals became smaller with the distance from the shelterbelt, 4) similarity of macrofauna communities in terms of composition and dominance structure, with increasing distance between plots. Close relationship was found between plant cover and soil-litter macrofauna. Species composition, density, biomass and trophic structure of soil invertebrate community depended on tree or herb species. Those soil animals and especially dipteran larvae were a sensitive indicator of small-scale habitat changes.
Species composition, dominance structure, and phenology of bees (Apiformes) was studied in the Białowiea National Park, which is a part of the most extensive primeval forest on the European Plain, the Białowiea Forest (NE Poland). In total 146 species of Apiformes are reported from the park. Beside the more or less abundant honey bees, the major bee species is Bombus lucorum, accounting for about 30% of wild bees and as much as 71.5% of bumblebees recorded there. Among 3 other bee species dominating in a large part of Poland, Bombus pascuorum accounts for nearly 11% of bumblebees, while B. terrestris and B. lapidarius are accessory species in the park. This shows approximately how the bee fauna looked like in most parts of Poland and Central Europe before human activity started to change the landscape radically, starting from the Middle Ages.
Communities of bees (Apiformes) were studied in the Wolin National Park in 2002-2003. The Park is located on the island of Wolin in northwestern Poland, at the southern coast of the Baltic Sea. In total, 133 bee species were recorded there in various habitats. This study shows that the major role in protection of bee communities is played by xerothermic and sandy grasslands. They are distinguished by the highest species diversity of Apiformes, including Anthophora bimaculata and its nest parasite Ammobates punctatus (rare in mainland Poland). In contrast, coastal grey dunes support mostly bumblebees, including cuckoo bumblebees.
Species diversity and ecology of bees (Apiformes) was studied in the Masurian Landscape Park (NE Poland). The Park is dominated by woodland (50%) and lakes (30%). In total, 153 species were recorded there, which account for 32.6% of the Polish bee fauna. In the study area, the bee fauna is characterized by a lower diversity of Halictidae and a high diversity of Apidae. One of the dominant species is Andrena lapponica, with two generations: in early spring (myrtillus generation) and spring (vitis-idaea generation). This contrasts with earlier reports that this species is univoltine.
Studies were carried out in the vicinity of Turew near Poznań (Western Poland) in the years 2003 and 2004 in three midfield shelterbelts of different age (150, 11, 6 years old) and along two transects across shelterbelt (6 and 11 years old) >ecotone> field at distances 15 and 50m from the shelterbelt. The field located in deforested area was treated as the control. The studies were aimed at estimating the changes in community structure (composition, density, biomass) of soil and litter macrofauna, (mainly dipteran larvae), related to shelterbelt age both within shelterbelts as in adjoining fields. The results were compared to previous studies carried out in 1999–2000 in the same agricultural landscape. The density and biomass of soil and litter macrofauna were many times higher in shelterbelts (2827–870 ind. m⁻² and 3782–521 mg.d.wt. m⁻²) than in fields (483–53 ind. m⁻² and 101–12 mg.d.wt. m⁻²) and increased with the age of planted trees. The same was true for taxonomic richness. Ecotone zone of both transects was characterised by the greatest density and biomass of animals, mainly those of mobile epigeic animals, particularly the ants. The density and biomass values were declining in the field with the increasing distance from the shelterbelt. Across the transect of an older (10–11 years old) shelterbelt and adjacent field the density and biomass of studied animals were higher in all plots than across the younger (5–6 years old) one. It can be concluded, that the effect of the shelterbelt increases with age of planted trees. The results confirm the previous suggestions of the enhancement of the field macrofauna by forested strips. The highest similarity in taxonomic and dominance structure was found between the shelterbelts and their ecotones and they differed significantly from those in the field.
The paper deals with the composition, density and biomass of soil-litter macrofauna in four midfield shelterbelts of different age and, comparatively, in the neighbouring mixed forest. The increase was observed along with the shelterbelt ageing of: 1) numbers of all macrofauna and particularly of some taxa (Symphyla, Chilopoda, coleopteran larvae and imagines and some dipteran larvae), 2) biomass of all macrofauna, of soil fauna (Group I) and of coleopteran larvae, 3) share of zoophages in all macrofauna and in dipteran larvae, 4) share of phytophages in coleopteran larvae communities, 5) average individual biomass, 6) taxonomic richness and the biodiversity (H’), 7) similarity of composition and domination structure of all macrofauna and of dipteran larvae to those in forest communities. The decrease of density of dipteran larvae, particularly of Chironomidae and Sciaridae and the share of saprophages in all macrofauna and in dipteran larvae was also observed. Successional stages of more numerous invertebrate taxa in newly established woodlots are described. Dipteran larvae were the pioneers in colonising newly established shelterbelts, particularly larvae from two families: Chironomidae and Sciaridae. Their combined contribution to the total density of dipteran larvae was 92%.
The distribution of staphylinid (Coleoptera: Staphylinidae) associations in the coastal variety of coniferous forest type (Empetro-nigri Pinetum) is described over the last century. The study area (UTM - XA56) has been subject to very limited anthropopressure and it may be, therefore, considered as a nearly unchanged environment. Thirteen distinguishing species were identified in the stable entomocoenosis; they should constituted at least 20% of the total number of specimens in the community. The staphylinid association was named „Tachyporus corpulentus - Sepedophilus marshami - Tachyporus transversalis ”. Its full description was based on four attributes: dominance structure, species fidelity, microsite preferences and geographical distribution.
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