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PL
Czy gatunki inwazyjne, będące zarazem gatunkami obcymi, powinny w naszych lasach występować, czy może należy je bezwzględnie eliminować jako osobniki zagrażające różnorodności biologicznej ekosystemów leśnych i powodujące zamieranie gatunków rodzimych?
EN
So far in Poland, the Asian clam Corbicula fluminea has been reported from the Oder (Odra) and Vistula River. Its new population has been discovered in the Warta-Gopło Canal in Konin (central Poland), where water temperature can reach 34°C, as the canal is a part of a power plant lake cooling system. The spatial distribution of C. fluminea was found to be very uneven and that is probably why this species was not found during earlier research. The highest density of C. fluminea was 78 ind.·m-2 at the site where water flow was the fastest (2.49 m·s-1), providing sufficient oxygenation of the water. The results suggest that existing information about the distribution of C. fluminea may be far from complete because the clam can be present also in the habitats that were not regarded as suitable for the species according to earlier reports, and therefore have not been monitored for its presence.
3
Content available remote Obce gatunki mszyc w Polsce (Hemiptera: Aphidoidea)
PL
W Polsce stwierdzono występowanie około 800 gatunków i podgatunków mszyc (Hemiptera: Aphidoidea), z których prawie 40 taksonów jest obcych dla rodzimej fauny. Liczba nowych gatunków wzrasta, fitofagi te często są transportowane przypadkowo, z roślinami sprowadzanymi do Polski. Wzrost średniej rocznej temperatury przyczynia się do poszerzania zasięgów występowania ciepłolubnych gatunków mszyc, wpływa na cykle życiowe oraz na ich bionomię.
EN
There are around 800 species and subspecies of aphids (Hemiptera: Aphidoidea), of which nearly 40 are alien to the local fauna. The number of new species has been growing, with phytophages often transferred accidentally with plants imported to Poland. Increase in the average annual temperature contributes to the widening of the occurrence range of thermophilic species of aphids influencing their life cycle and bionomy.
EN
Learning mechanisms determining fish reproduction are particularly beneficial in the case of experimental work on juvenile forms of fish making research independent of the season of the year. This paper describes the reproduction method of the round goby, Neogobius melanostomus, under controlled conditions. This species is not native to the ichthyofauna of the Gulf of Gdańsk and was discovered here for the first time in 1990. In the case of pre-seasonal reproduction of the round goby, the first spawning took place 5 weeks after the beginning of thermal stimulation. On the other hand, artificial reproduction of the fish caught in the spring was possible after only a week of being kept in a temperature of 17-19°C. The spawn incubation period ranged from 17 to 22 days, depending on the temperature. For natural spawning, the period from spawning to hatching was 18-19 days, at a constant temperature of 20°C.
PL
Poznanie mechanizmów warunkujących rozród ryb jest szczególnie korzystne w przypadku prac doświadczalnych na formach juwenilnych ryb, gdyż uniezależnia prowadzenie badań od pory roku. Praca opisuje metodę rozrodu babki byczej N. melanostomus w warunkach kontrolowanych. Gatunek ten nie jest rodzimym składnikiem ichtiofauny Zatoki Gdańskiej i został tu po raz pierwszy stwierdzony w 1990 roku. W przypadku przedsezonowego rozrodu babki byczej pierwszego tarła doszło po 5 tygodniach od rozpoczęcia stymulacji termicznej. Sztuczny rozród ryb odłowionych na wiosnę był natomiast możliwy już po tygodniu przetrzymywania w temperaturze 17-19 °C. Okres inkubacji ikry wynosił od 17 do 22 dni w zależności od temperatury. Dla tarła naturalnego czas od tarła do wylęgu wynosił 18-19 dni przy stałej temperaturze 20 °C.
EN
The signal crayfish Pacifastacus leniusculus (Dana, 1852) of North American origin was introduced to Europe (to Scandinavia) in the 1960s. Since that time due to translocation to many countries, biological features and ecological plasticity, it became widespread, invasive and displaced native species. The paper reports first multi- point colonization of P. leniusculus in the Polish rivers. The aim of the study was to determine the current distribution of the signal crayfish in the coastal Baltic tributary (the River Wieprza) after 20 years of deliberate releases in its drainage area. During sampling at 28 sites with use of the “Pirate” crayfish traps and hand collection methods in spring and summer 2014, 127 P. leniusculus individuals were found at 8 sites in the Wieprza and its two tributaries, both away from and close to known sites of their introduction in 1995 and 1996 in the Wieprza River drainage area. The species spreads via the Wieprza River towards the Baltic brackish waters. With such expansion of this species, it is expected to be found in Polish coastal waters of the Baltic Sea and in other coastal rivers in the near future. The conflict between legal aspects of the signal crayfish farming, colonization by the species of the natural aquatic ecosystems and the expectations of consumers is discussed.
PL
Celem pracy jest określenie przydatności wskaźnika BPL (ang. biopollution level index) do oceny stanu biozanieczyszczenia polskiej części Zalewu Wiślanego. Na podstawie danych z lat 2010 i 2012 w akwenie odnotowano łącznie 15 gatunków makrozoobentosu, w tym 5 zaliczono do grupy gatunków nierodzimych: Marenzelleria neglecta, Rhitropanopeus harrissi, Potamopyrgus antipodarum, Dreissena polymorpha i Rangia cuneata. W oparciu o przyjęte kryteria i dane literaturowe dotyczące wpływu obcych gatunków na środowisko, stan biozanieczyszczenia Zalewu Wiślanego został oceniony jako średni.
EN
This paper presents biopollution assessment results with respect to macrozoobenthic non-indigenous species in the Polish part of the Vistula Lagoon. A biopollution level index (BPL) was applied and evaluated based on the studies on macrozoobenthos conducted in 2010 and 2012 within the frame of several individual projects. Overall 15 macrozoobenthic species were identified, 5 of which were aquatic alien species: Marenzelleria neglecta, Rhitropanopeus harrissi, Potamopyrgus antipodarum, Dreissena polymorpha and Rangia cuneata. According to the applied criteria the Vistula Lagoon was moderately influenced by invasive species.
EN
The publication presents an evaluation ofhealth status of roadside trees (growing between the road and the pavement) in the central part of the city of Opole. To assess the health condition of the trees the method proposed by 1. Duda was used, whereby the health of a tree is assessed in the twelve gradual scale. Among the surveyed trees, 13 species were found, of which the most abundant, constituting 63.8% of the examined group were: TWa cordata, Aesculus hippocastanum, Robinia pseudoacacia, Tilia platyphyllos. Eight native and five alien species in the domestic flora were distinguished. Among the studied objects definitely the largest share - 78.1 % had the trees in good health. The specimens in poor and very poor condition constituted 19.3% and 2.6% respectively. In the group representing the native species oftrees, 75.7% of the specimens in good condition, 21.0% in poor and 3.3% in very poor was noted, while among the alien species 81.4% were in good condition, 16.8% in bad and 1.8% in very poor. Among the factors negalively affecting the health status oftrees, mechanical damages, chloroses, pathogens and pests were identified.
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