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Sylwan
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2015
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tom 159
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nr 06
Beavers activity i.e. dam building, burrows and canals digging and foraging, radically changes the environment at both abiotic and biotic level. The consequences of beavers activity for other organisms are visible mainly through changes in their habitats. Such changes influence the number, species composition and species diversity of numerous flora and fauna species. One group of species that also may be influenced by beavers activity are small mammals (Rodentia and Soricimorpha). In Bieszczadzki and Magurski National Parks (southern Poland), small mammals community has not been studied at beaver sites yet. The aim of this study was to determine species composition, species diversity, and the relative abundance of small mammals at beaver sites, comparing to sections of the stream not inhabited by beavers (control sites). Small mammals were captured in three types of habitats – meadow, forest and riparian woodlots. Transects with live−traps were set there within beaver and control sites. Captures were conducted from one to three times annually, during 2−3 consecutive years. Total trapping effort amounted to 2540 trapdays. It was found that species composition, species diversity, and also the relative abundance of small mammals did not differ significantly between beaver and control sites. Only M. agrestis had significantly higher share in the community at the beaver sites. In mountain conditions, the presence of beaver sites probably does not affect the communities and abundance of small mammals significantly.
The paper addresses the following issues: (1) does the bank vole response to odours of other rodent species by urine and faeces marking (2) does this reaction depend on the species, (3) does the amount of odour influence the marking, and (4) the response of bank voles to the presence of heterospecifics, and its comparison with the response of marking the odour deposited by these species. The study was conducted in a Ribo nigri-Alnetum swamp located in the Kampinos National Park, central Poland (52°20’N and 27°25’E). To observe scent marking, white paper sheets (15 × 21 cm) supplied with sponges (1cm³) soaked in odour of particular rodent species were exposed in the forest along a line ca 1200 m long. Odour donors were countryside species: a) phylogenetically close to the bank vole, such as Microtus agrestis (L.) and M. oeconomus (Pallas), b) sympatric, such as Apodemus flavicollis (Melchior) and A. sylvaticus (Melchior), or occupying a different habitat A. agrarius (Pallas), and allopatric species such as Meriones unguiculatus (Milne-Edwards), Mesocricetus auratus (Waterhouse), and Octodon degus (Bennet). Also sheets with the odour of bank vole and control sheets without odour were exposed. Marking was analysed basing on the number of marked sheets (marking extensity), and on the number of urine and faeces marks on sheets (marking intensity). During the three study years, a high marking extensity was observed for the odours of phylogenetically close species. The odours of sympatric species were marked less frequently and with a higher variability in successive years. The lowest marking extensity was found for geographically alien (allopatric) species. The mean number of marks per sheet did not differ significantly between the species. To examine the effect of odour quantity on marking, a line (ca 630 m long) made up of sheets provided with 1, 3, and 5 sponges with M. oeconomus and C. glareolus odour, and of control sheets was established. The increase in the number of sponges with heterospecific odour had no effect on the extensity and intensity of marking. Significant difference in marking extensity, but not in marking intensity, was found in the case of conspecific odour. The response of bank voles to the presence of heterospecifics was examined based on the number of captures in double-traps with a live individual. In the forest, a line of 30 double-traps placed every 10 m was established, containing single M. oeconomus, A. flavicollis, or C. glareolus. Bank voles were more often captured in traps with conspecifics than with heterospecofics. Thus, bank voles avoid encounters with heterospecifics but they do not avoid marking their odour (marking the heterospecific odour was not lower than marking conspecifics and control). It may suggest that under natural conditions, interspecific communication is largely mediated through olfactory cues.
W połowie lat 70. ubiegłego wieku, nad górnym Sanem, na obszarze ok. 1500 ha, rozpoczęto tworzenie fermy rolno-hodowlanej „Igloopol”. Spośród prowadzonych zabiegów gospodarczych szczególnie niekorzystne dla lokalnego środowiska były melioracje wodne i agrotechniczne. Po kilkunastu latach ferma upadła, a po kilku następnych, w listopadzie 1999 roku, została ostatecznie przekazana do Bieszczadzkiego Parku Narodowego. Zgodnie z wytycznymi planu ochrony Parku opracowano założenia postępowania w dolinie Sanu określone jako program renaturyzacji, w którym m.in. za istotne przyjęto: 1) sanację stosunków wodnych, 2) aktywną ochronę cennych elementów przyrodniczych i kulturowych, 3) inicjację odtwarzania zarośli i zadrzewień łęgowych. Prace renaturyzacyjne w dolinie rozpoczęto w 1992 r. Miały one na celu zabezpieczenie torfowisk wysokich i polegały one na usypaniu przetamowań ziemnych na rowach opasujących i odwadniających 8 torfowisk. Po przejęciu terenów „Igloopolu” w 1999 r., BdPN kontynuował zabiegi renaturyzacyjne polegające głównie na spowalnianiu spływu wód powierzchniowych (zastawki ziemne) i odtwarzaniu zbiorowisk łęgowych. Jesienią 1992 r., w leśnictwie Górny San BdPN, rozpoczynając program reintrodukcji bobra europejskiego wsiedlono 2 rodziny, a następnie corocznie zasilano lokalną populację nowymi osobnikami z Suwalszczyzny. Spodziewano się, że bóbr będzie pełnił istotną rolę w procesie renaturyzacji doliny. Po kilku latach obserwacji, oceniając efekty obecności bobrów uzyskano wyniki, które w pełni potwierdziły słuszność tych założeń. Działalność bobrów, w szczególności budowanie tam na ciekach wodnych i tworzenie rozlewisk (stawów bobrowych), doprowadziła do znacznego wzrostu retencji wody, spowolnienia przepływu wód oraz zwiększenia sedymentacji osadów dennych. Zmiany w środowisku wywołane przez bobry w istotny sposób przyczyniły się do wzrostu różnorodności biologicznej – zwiększyła się liczba gatunków flory higrofilnej i gatunków zwierząt związanych ze środowiskiem wodnym. Niniejszy artykuł jest próbą podsumowania dotychczasowych efektów wprowadzenia bobra europejskiego jako elementu procesu renaturyzacji doliny górnego Sanu w Bieszczadach.
Opisano nowe stanowisko ryjówki górskiej Sorex alpinus (Schinz, 1837) w Beskidzie Niskim. Ryjówkę stwierdzono na terenie Magurskiego Parku Narodowego, gdzie gatunek ten nie był dotychczas notowany. Miejsce odłowu zlokalizowane było w południowo-wschodniej części Parku, koło miejscowości Huta Krempska (49°29´6˝ N, 21°30´24˝E), na wysokości 470 m n.p.m. Ryjówkę złowiono w strefie przybrzeżnej potoku górskiego w sierpniu 2009 roku. Stwierdzenie nowego stanowiska wypełnia lukę w rozmieszczeniu tego gatunku na granicy Karpat Wschodnich i Zachodnich
Occipitalization of the atlas is an osseous anomaly of the craniovertebral junction. The aim of this paper is to present an anatomical variant of the fused atlas with the occipital bone and discuss similar cases described in literature. The skull of an adult male analysed in this study belonged to the cranial collection of the Department of Anatomy of the Jagiellonian University, Medical Collage. A tight bony fusion between the anterior arch of the atlas, the left portion of the posterior arch, the lateral masses of the atlas, and the occipital bone was observed. Hence, the left and right superior articular facets of the atlas were fused with the corresponding occipital condyles. The anteroposterior dimension of both inferior articular facets was the same (20 mm), while the transverse diameter of the right one was considerably smaller (12 mm). The transverse diameter of the left inferior articular facets was 17 mm. The right and the left transverse process of the atlas were normally developed, each of them contained transverse foramen, and they were not fused with the occipital bone. The circumference of the foramen magnum was minimally diminished by the osseous structures of the atlas fused to the occipital bone. The sagittal and transverse diameters of the foramen magnum (38 mm x 34 mm) were within the normal range of variation. However, the asymmetrical anatomy of the inferior articular facets of the atlas give rise to speculation that movement in the atlantoaxial joint was disturbed by assimilation with the occipital bone. (Folia Morphol 2010; 69, 3: 134–137)
This report describes the topography and structure of the petroclinoid ligament with reference to its clinical significance. Observations of this ligament were performed on 24 sections of human heads. Remnants of the ossified form of this ligament were sought in 73 dry human skulls. It was found that the petroclinoid ligament existed as an anterior and posterior fold of the dura mater and stretched from the petrous apex and the anterior and posterior clinoid process respectively. We assessed the close proximity of this ligament to the oculomotor nerve. In one case we found a partially ossified posterior petroclinoid ligament, which appeared as a bony spike that arose posteriorly and inferiorly from the posterior clinoid process.
This paper presents the case of an adult male skull with bilateral ossification of the stylohyoid complex. The total length of the stylohyoid complex amounts to 62 mm on the left side and 65 mm on the right side. Visual inspection of the stylohyoid revealed the presence of callosities that are located on both stylohyoid complexes at nearly the same level. These sites are regarded as the ossified attachments of the stylohyoid ligaments to the corresponding styloid processes. The skull studied is an example of extreme development of the stylohyoid complex, which could cause severe pain and a restriction of head and neck movement.
A method was proposed for studying population density, microhabitat preference, daily activity and seasonal activity in small rodents. In this method, artificial tunnels (PVC pipes) imitating a natural system of burrows were applied. Their use by rodents was recorded by means of the electronic counters provided with a photoelectric cell. The study was conducted in an alder swamp 110 years old, located in the Kampinos National Park (52°25’N, 20°53’E) during 2003–2005. In this area, the bank vole Clethrionomys glareolus (Schreber, 1780) accounted for 90–99% of the captured rodents. The use of the tunnels by rodents (the number of passages) did not depend on their length within a range of 1–8 m applied in the experiment (P = 0.22). The tunnels were used by day and night, at the highest rate in the evening and at night. The use of tunnels increased when a bait was exposed in the vicinity (P = 0.001). It was positively correlated with population density (estimated with the CMR technique), and varied from season to season (in spring, summer, and autumn). The formula: density = 0.1717 + 0.0304 × mean number of passages per day, enabled the estimation of population density based on the number of passages through the tunnels. It has been found that a single tunnel was typically used by 5 individuals (mean 4.6 individuals, SD = 1.8). The location of tunnels had a significant effect on their use. Tunnels connecting fallen logs or bases of alders (hummocks) were more frequented than those leading to shrubby areas (P <0.000) or to microhabitats covered with herbaceous vegetation (P <0.001). This method enabled a multisided analysis of the behaviour of rodents at a minimum interference in the life of animals. Thanks to the application of electronic counters of passages, it was possible to obtain easily a large number of data. It is proposed to mark rodents with electronic transponders in the future studies to identify the individuals using artificial tunnels. This method could replace the methods used so far in the studies of small rodents, requiring trapping (CMR) or radio-telemetry.
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