Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 19

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  geographic range
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
In Poland, feral population of the American mink Mustela vison Schreber, 1777, originating from the immigrants from Belarus and Lithuania, as well as from Polish fur farm escapees, started to develop in the beginning of 1980s in the north-east and north-west of the country. According to questionnaires sent to hunters, up to the end of 1980s mink colonized 9 out of 16 Polish provinces. Within next decade mink were observed in next 6 provinces. In Warmińsko-Mazurskie and Podlaskie provinces (north­-eastern Poland) mink presence has been confirmed by over 90% of hunting units, whereas in the north-west of the country by over 50% of respondents. In southern provinces mink are still uncommon but they successfully enlarge geographical range. During the 20-year period, mink have colonized over half of the Polish territory. Colonization of particular regions was correlated in time with a decline of muskrat and waterfowl populations. From the beginning of 1980s to the half of 1990s, in north­eastern provinces hunting bag of muskrat decreased 10-fold, whereas in other parts of Poland the number of hunted muskrats was more or less stable. Despite the lack of complex ecological studies on the mink impact on their prey, it is highly probable that this introduced carnivore negatively affects populations of semi-aquatic birds and mammals.
The work presents information about the range, occurrence conditions, geographical and historical status and dynamic tendencies of Melilotus wolgica in Eurasia and Poland. In Poland, the species was noted for the first time in Szczecin at the end of 19th century. Later, it was observed in the anthropogenic localities in the Opole Province, Kraków and Warszawa. In Wielkopolska, M. wolgica was observed for the first time in 2012, south of Gosławice (Konin district), where a large population was found on the embankment of a coal ash storage reservoir of the Konin Power Plant in the former brown coal mine area.
In the studies on the metapopulation system two aspects are important: cognitive and practical. The former indicates that a metapopulation is a demographic structure of a higher level than coenotic or local populations and aims at recognition of relations between particular populations of a given species. The practical aspect reflects the issues of the dynamics and/or the extinction rate in particular populations and indicates potential habitats which can be colonized. The study of the Senecio rivularis metapopulation is created by relatively abundant population of ragwort in the Roztocze Highlands, Roztocze National Park, south-eastern Poland, recognized as the source population and three other called marginal or sink populations as well as potentially suitable habitats which are distributed as islands in adjacent hydrogenic areas. The distances between particular populations range from 1.3 to 6.5 km. As a long-lived, iteroparous rhizomatous clonal plant, insect-pollinated and anemochoric one, so having adaptations both for ‘escape in time’ and ‘escape in space’, S. rivularis may be treated as the model object of the study on the metapopulation level. The following hypotheses were put forward: (1) the spatial pattern, size and life-stage structures of particular populations reflect the time of their origin in the meta-system; (2) hydrochory is a complementary or alternative way of migration of anemochoric diaspores; (3) local watercourses and hydro-technical activity affect the formation and dynamics of S. rivularis metapopulation. The multi-aspect studies of the source population were conducted in the years 1987–2007. They aimed to establish the density, spatial pattern and life-stage structure of the S. rivularis population, both at a large scale, i.e. in the whole population (three times) and at a small scale, i.e. on the level of three particular clumps (four times). The size structure of generative genets and ramets in the whole population was elaborated five times. In the greatest of the other populations in the meta-system, the size structure was elaborated twice (2002, 2007) while the study of spatial and life-stage structures was done only once, in the first period, because of the disturbance of a greater part of the population in the next years. In the two remaining localities all plants were counted thanks to small abundance of the populations. Considerable changes in the spatial organization and life-stage structure of genets in the source and sink populations exhibited that colonization in the meta-system of S. rivularis proceeds in accordance with an island model of the ‘stepping stone’ type, downstream the river. Renaturalization of water relations of river catchment areas and construction of the so-called small retention objects affect the formation and dynamics of S. rivularis metapopulation which reflects at least some dynamics phases observed at the level of the source population: progressive, stable, fluctuation and/or regressive, and extinction phases. Knowledge of the density, life-stage and size structures of plants in a population facilitates a highly reliable determination of the development phase of a given local population in the meta-system and prognosis of its future.
Three new sites of Orobanche arenaria were discovered during floristic investigations in the Wyżyna Małopolska upland in central Poland. The new localities are concentrated in the Ponidzie area (Garb Piriczowski ridge and Niecka Polaniecka basin) and form the northern limit of the geographical range of O. arenaria. The paper presents information on the distribution of Orobanche arenaria in Poland, the abundance at the sites and habitats occupied by the species.
New localities of Arnoseris minima (L.) Schweigger et Koerte (Asteraceae) in the Podlasie region (NE Poland) are presented. The current distribution of the species was established on the basis of the authors’ floristic field studies, revised herbarium materials, published data, and unpublished sources. The collected data enabled us to revise the map of the species’ distribution in the Podlasie region and supplement it with another new 17 localities. The previously established geographic range of species in Poland can now be moved by about 30 km eastwards and 50 km northwards. The identification of new locations of A. minima on the border of its continuous geographical range becomes important in the context of the declining number of localities of this species recently observed across almost the whole of Europe.
Pseudogilquinia pillersi (Southwell, 1929), a poorly known species of trypanorhynch, is redescribed from plerocerci collected from Epinephelus coioides (Hamilton, 1922), Epinephelus malabaricus (Bloch et Schneider, 1801) (Serranidae) and Plectropomus laevis (Lacépède, 1801) (Serranidae) off New Caledonia. These were compared with specimens from Lethrinus atkinsoni Seale, 1910 and Lethrinus miniatus (Forster, 1801) (Lethrinidae) off the north-east coast of Australia as well as syntypes from Protonibea diacantha (Lacépède, 1802) from Sri Lanka. Although size differences were found in parts of the scolex as well as in the sizes of the tentacular hooks, the hook arrangements were identical in all specimens. The differences observed were attributed provisionally to intra-specific variation across a wide geographic and host range.
Three populations of Abies cilicica subsp. isaurica and four of A. cilicica subsp. cilicica were analyzed using 35 morphological and anatomical needle characters with the implementation of multivariate statistical methods to verify the differences between subspecies. Moreover, the possible geographic differentiation of A. cilicica subsp. cilicica populations from the East Taurus and Lebanon Mountains was examined. Abies cilicica subsp. isaurica has been distinguished from A. cilicica subsp. cilicica by its glabrous young shoots and resinous buds. We detected that needles of A. cilicica subsp. isaurica are longer, broader and thicker, with a higher number of stomata rows, and larger cells of the epidermis, hypodermis and endodermis than A. cilicica subsp. cilicica. Additionally, A. cilicica subsp. isaurica needles have frequently rounded to obtuse-acute apex and resinous canals positioned more centrally inside the mesophyll than needles of A. cilicica subsp. cilicica. This indicates that a set of most of the tested needle characters can be used to distinguish the subspecies; however, any of characters enable that when used separately. Morphological and anatomical distinctiveness between these two taxa justify their recognition at the subspecies rank. Additionally, the populations of A. cilicica subsp. cilicica from the East Taurus and Lebanon are morphologically different. This geographic differentiation of populations is congruent with results provided by genetic analyses of nuclear microsatellites markers (nSSR).
The paper presents the current distribution of Orobanche picridis in Poland and Ukraine, within the Polish borders in the interwar period, based on a critical revision of herbarium and literature data as well as the results of my field studies. The largest number of its localities is in S and SE Poland in the Wyżyna Śląsko-Krakowska, Wyżyna Małopolska, Wyżyna Lubelska uplands, Middle Roztocze, Small Polesie, the Pogórze Przemyskie foreland and in the former Tarnopol province (W Ukraine). These are the north-easternmost sites known for the species and extend its limit range. A map of its distribution in Poland and Ukraine is included. The taxonomy, biology, and ecology of O. picridis are also discussed.
A new locality of Orobanche coerulescens Stephan ex Willd. in the Wyżyna Małopolska upland (Garb Pińczowski hummock) in central Poland is presented. Over 290 specimens were recorded in a xerothermic grassland of the class Festuco-Brometea comprising species of the class Koelerio glaucae-Corynephoretea canescentis on alkaline, sandy soil. O. coerulescens is extinct at the majority of its localities in Poland and only two localities are known at present.
Allium oleraceum L. and A. vineale L. are two related bulbous geophytes with an annual storage organ that coexist in a wide range of habitats but show both partly different geographic ranges and habitat preferences in Europe. To explore whether ecological and distributional differences between species can be related to expected variation in some key life-history traits between them, research was undertaken to compare the phenology, seasonal growth, and dry-mass allocation of vegetative and reproductive plants of the species at successional gradient comprising three sites with contrasting environmental conditions (steppe, scrub, forest), where populations of the study species coexist (the Czech Republic). The results showed, in general, partly different timing of phenophases between species and different responses of species to contrasting environmental conditions. A. vineale displayed an annual life cycle similar to that observed in many Mediterranean geophytes, i.e. regularly sprouting above ground before the arrival of winter, its growth was concentrated into early and mid-spring and started to wither after a temperature increase and several short-term drought events in early summer, though its flowering was delayed until late June. A. oleraceum showed high year-on-year variation in the onset of shoot elongation above-ground; its growth was concentrated into mid- and late spring and its flowering was delayed until July. The patterns of phenology observed between the study species thus partly reflect selection under different environmental conditions of their origin. The total duration of the green above-ground period of reproductive plants in both species continued about 1.5–2 months beyond that of the vegetative ones. Over main growth period, mean relative growth rates (RGR) of A. oleraceum and A. vineale ranged from 20 to 22 and from 6 to 28 mg g⁻¹dw day⁻¹, respectively. A. vineale showed significantly higher RGR than A. oleraceum only in steppe conditions while at shaded sites the reverse pattern was found. The RGR of both vegetative and reproductive plants of A. oleraceum did not differ from one site to another. On the other hand, both vegetative and reproductive A. vineale plants showed lower RGR at shaded sites than at steppe one. Shading increased allocation into leaves in both species, caused complete abortion of developing scapes in A. vineale but only reduced reproductive allocation in A. oleraceum. A. oleraceum was able to maintain fitnessrelated traits more stably across the environments studied than A. vineale that fit well into the pattern of habitat differentiation observed between them in Central Europe. Data concerning growth of and allocation into new bulb in both species also support the hypothesis that allocating reserves for the coming year is the first priority in geophytes with an annual storage organ.
Galium sect. Leptogalium Lange in NE Europe is represented by few, local endemic species which occur in the area covered by the continental ice sheet in the Pleistocene period. They are: G. cracoviense Ehrend. in S Poland, G. oelandicum (Sterner & Hyl.) Ehrend. in SE Sweden and G. sudeticum Tausch in SW Poland and N Czech Republic. 55 individuals from five populations of these species were analysed using AFLP markers. A total of 193 AFLP bands were detected using three combinations of primers; out of them 159 proved polymorphic (82.4%). The lowest values of Shannon's index and Nei's gene diversity were noted for G. oelandicum and the highest ones for G. sudeticum. The results indicate a relatively high level of genetic variability in each of endemic species in spite of that the studied species occupy very small areas and are represented by a low number of populations. We conclude that additional, demographic and genetic studies are necessary to monitor potential decrease of populations' size resulting mainly from the mechanical destruction of plants and their habitats caused by intense tourism or other human activities (as agriculture, e.g. grazing).
An overview on the myxosporean species infecting amphibians and reptiles is presented. The characteristics of the species are reported, as well as the pathology, hosts and geographical range. The host specificity and life cycle are discussed on the basis of the data thus far.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.