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Growth Rate, Age and Size Structure of the Alien Pumpkinseed, Lepomis gibbosus (L., 1758) Population from a Heated-water Discharge Canal of a Power Plant in the Lower Stretch of the Oder River, Poland

Domagała J., Czerniejewski P., Pilecka-Rapacz M.

Rocznik Ochrona Środowiska

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2016

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Tom 18, cz. 1

273--290

EN

In 2010-2013, 1077 pumpkinseed individuals were caught using an electric pulse device and subjected to population studies aimed to determine their sex, length and age structure, as well as biological studies assessing fish growth rate and condition. Moreover, an annual cycle of seasonal changes in these parameters was demonstrated. In the sex structure of the population, males prevailed over females, constituting 57.38% and 33.43%, respectively, while individuals of unspecified sex were 9.19% (including 3.9% of juvenile individuals). The mean total length (TL) of the caught fish was 162.62 mm, with the mean weight per individual of 83.21 g. Among the caught fish, males represented 70.07% and females represented 29.93%. As regards the age structure, most individuals belonged to the groups aged 3+ and 4+, which together constituted 58.31% of the fish. The mean weight per individual of the caught pumpkinseed was 41.65 g (SD = 24.81), with a total length of 11.98 cm (SD = 2.97). The largest annual increments in the length of the investigated fish were observed in the first year of life (5.87 cm), with increments nearly 3 times lower in the following years. The growth rate of the pumpkinseed was significantly higher in comparison to the populations inhabiting other European waters and was similar to the fast-growing populations occurring in the natural range of occurrence. The probable factor allowing the higher growth rate of the pumpkinseed in the Warm Canal is water temperature much higher than that in natural waters.

PL

Bass słoneczny jest gatunkiem obcym w wodach Europy, a występowanie populacji jest punktowe i ograniczone tylko do wód o korzystnych warunkach środowiskowych dla tego gatunku. W Polsce rozsiedlony jest w wodach kanału ciepłego elektrowni Dolna Odra, o termice wody znacznie wyższej niż w wodach naturalnych. W latach 2010-2013, przy pomocy elektrycznego urządzenia impulsowego, do badań złowiono 1077 bassów słonecznych, które poddano badaniom populacyjnym określając struktury płci, długości i wieku oraz biologicznych, oceniając tempo wzrostu długości i kondycję ryb. Ponadto wskazano sezonowe zmiany tych parametrów w cyklu rocznym. W strukturze płci dominowały samce, stanowiące 57,38%, samice stanowiły 33,43%, natomiast osobniki z nieoznaczoną płcią 9,19%, w tym osobniki juwenilne 3,9 %. Średnia długość całkowita (TL) złowionych ryb wyniosła 162,62 mm, przy średniej masie jednostkowej 83,21 g. Wśród złowionych ryb dominowały samce stanowiące 70,07% ryb, samice stanowiły 29,93%, W strukturze wieku ryb najwięcej osobników stwierdzono w grupach wieku 3+ i 4+, które stanowiły łącznie 58,31% ryb. Średnia masa jednostkowa złowionych bassów wyniosła 41,65 g (SD = 24,81), przy długości całkowitej 11,98 cm (SD = 2,97). Największe roczne przyrosty długości u badanych ryb zanotowano w pierwszym roku życia (5,87cm), podczas gdy w kolejnych przyrosty były blisko 3 krotnie niższe. Tempo wzrostu długości bassów słonecznych było zdecydowanie wyższe w porównaniu do populacji zamieszkujących inne wody Europy i zbliżone do szybkorosnących populacji występujących w naturalnym zasięgu występowania. Prawdopodobnie czynnikiem warunkującym szybki wzrost bassów z wód kanału ciepłego jest woda o podwyższonej termice w stosunku do wód naturalnych.

2

Struktura populacji cisa pospolitego Taxus baccata L. w Wysokiej Lelowskiej

Majchrzak B., Tomala R.

Chemistry, Environment, Biotechnology

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2015

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Vol. 18

19--30

PL

Badania populacji cisa przeprowadzono w latach 2010‒2011 w Wysokiej Lelowskiej niedaleko wsi Żarki Letnisko i Przybynów. Wyznaczono 4 poletka badawcze o wymiarach 10 × 20 m. Dla każdego poletka oznaczono wszystkie gatunki roślin, sporządzono listę florystyczną oraz wykonano zdjęcie fitosocjologiczne w aspekcie wiosennym i letnim. Na tej podstawie określono zbiorowisko roślinne jako zdegradowaną postać Fraxino-Alnetum. Populacja cisa składa się z 71 osobników, u których wykonano pomiar wysokości i pierśnicy. Pierśnica cisów zawiera się w przedziale 1‒29 cm. Średnia grubość wynosi 7.27 cm, a średnia wysokość wszystkich osobników to 6.98 m. Najwyższy cis mierzy 13.3 m. Większość cisów jest rozgałęziona (59%) i posiada najczęściej 5, 3 lub 2 pnie. 38% populacji jest jednopniowa. 2 osobniki (3%) mają formę krzewiastą. Średnie zagęszczenie cisów na wszystkich powierzchniach badawczych wynosi 8.8/100 m2. Struktura płciowa została określona dla 97% populacji: 62% to osobniki żeńskie, a 33% męskie. Pomimo przewagi liczby osobników żeńskich w Wysokiej Lelowskiej, populacja nie odnawia się. Odnaleziono tylko 6 siewek o wysokości do 10 cm. Powodem braku odnawiania się cisów może być nadmiernie rozwinięte runo. Z uwagi na dużą liczbę osobników cisa oraz ich dobrą kondycję, badana populacja powinna zostać objęta ochroną rezerwatową.

EN

The research of yew population was carried out in the years 2010‒2011 in Wysoka Lelowska near villages Żarki Letnisko and Przybynów. 4 research plots were established, 10 × 20 meters in dimension. For each research plot, all species was marked and the floristic list was made. The phytosociologial analysis was made in terms of spring and summer. On this basis was stated that the plant community is a degenerated form of Fraxino-Alnetum. The yew population consist of 71 specimens were measured in terms of height and breast height. Breast height of yews ranged between 1 and 29 cm. The average diameter is 7.27 cm and the average height of all specimens is 6.98 m. The tallest yew has reached 13.3 m in height. Most of the yews are branched (59%) and had 5, 3, 2 trunks. 38% population have a monopodium. Two specimens (3%) had a shrubby form. The average density of yews on all plots is 8.8/100 m2. Sex identity was determined in 97% of yews population: 62% were male and 33% female specimens. Despite, that the presence of the female specimens population in Wysoka Lelowska is not regeneration. The seedlings were found in the amount 6 of up to 10 cm. Maybe for reason the yews are not regeneration is over-developed undergrowth. Due to the large number of yews and good condition this population should be protected in nature reserve.

3

Age structure and reproduction rates of the ring-necked pheasant (Phasianus colchicus L.) population in agriculture landscape (Czech Republic)

Zíka T., Šálek M., Holá M., Hanzal V., Hart V., Kušta T., Ježek M.

Polish Journal of Ecology

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2014

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Vol. 62, nr 4

751--759

EN

Detailed knowledge of demographic parameters (such as age structure and reproduction rates) is crucial for guiding conservation and management decisions regarding wildlife populations. Such parameters of wild ring-necked pheasant populations in the current agricultural landscape remain very poorly described. We researched age structure and reproduction rates of predominantly wild populations of the ring-necked pheasant (Phasianus colchicus L.) across the intensively managed agricultural landscape of the Czech Republic. The study area is influenced only marginally by hand-reared pheasants (i.e. as shown by comparison of the average number of released individuals in the study area: 0.3 ♂/yr/1km2 and 0.9 ♀/yr/1km2 and average number of released individuals and harvested in the study area: 8.6 ♂/yr/1km2) and there is a long-term huntable pheasant population. To determine the age of individuals, we used proximal primary feather shaft diameters of 1487 feather samples from males hunted between 2009 and 2011. Moreover, we evaluated the age structure of females as well as both sexes together based on the sex ratio and annual game census. We found a relatively high proportion of adults in the population in comparison with other studies. However, the number of adults decreased throughout the years: 2009 (♂ 44.7%; ♀ 69.5%; ♂♀ 60.7%), 2010 (♂ 35.2%; ♀ 61.3%; ♂♀ 51.5%), 2011 (♂ 29.8%; ♀ 57.4%; ♂♀ 47.0%). The decrease of adults went hand in hand with increase of juveniles and reproduction rates of the study population: 2009 (♂ 124%; ♀ 44%; ♂♀ 65%), 2010 (♂ 184%; ♀ 63%; ♂♀ 94%), 2011 (♂ 236%; ♀ 74%; ♂♀ 113%). Only males were hunted in the study area so we determined higher proportions of females in population for all years. This is the main reason why the reproduction rate of females was lower in percentage expression. Generally, our results showed lower productivity of pheasants in the Czech agricultural landscape in comparison with earlier published studies conducted in the US and UK. However, these studies were published many years ago and thus do not reflect the actual environmental conditions and changes which took place recently (i.e. agricultural intensification).

4

Phylogenetic discontinuity of plateau zokor (myospalax baileyi thomas) populations in qinghai-tibetan plateau

Tang L., Zhang T., Lin G., Su J.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

167-176

EN

Mitochondrial cytochrome b gene sequences and morphological data (body length, hind foot length, etc.) for twelve populations with pairwise distances 27-600 km in Qinghai-Tibetan Plateau (distributed in Qinghai, Gansu and Sichuan Province, and at the altitude 3020-4550 m) in Western China were used to investigate the phylogeographical pattern of Plateau zokor (Myospalax baileyi Thomas). There was a little disparity between mtDNA genetic distance and morphological Euclidean distance on population relationships. However, there is a significant correlation (P <0.001) calculated by Mantel's tests was validated between mtDNA and morphology distances. Analysis of Molecular Variance showed that most of the observed genetic variations occurred between populations, indicating little maternal gene flow between them, as a result of geographical restrictions. Phylogenetic analysis coupled with cluster analysis together showed that the substantial population structuring and phylogenetic discontinuities existed within this species. The evident allopatric population structuring of this subterranean rodent may mostly result from its specialized subterranean excavating behavior with high energy costs, predation from grassland raptors and also the influences of perennial tundra and environmental desiccation in the Qinghai-Tibetan Plateau.

5

Population structure of a clonal endangered plant species Iris sibirica L. in different habitat conditions

Kostrakiewicz K.

Polish Journal of Ecology

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2008

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Vol. 56, nr 4

581-592

EN

The investigations of structure of the genets and populations of Iris sibirica L. were carried out in the period 1999-2002. The studies were conducted in Molinietum caeruleae patches localized in Southern Poland. The patch labelled MW ("more wet") measured 5,600 m[^2] and was chracterised by presence of large depressions filled with stagnant water, concentrated chiefly in the central part of the site. In this locality species with a high competitive potential (like Phagmites australis Trin., Chamanerion angustifolium (L.) Scop., Epilobium hirsutum L., Filipendula ulmaria (L.) Maxim. and others) prevailed. The patch called LW ("less wet") measured 1,800 m[^2] and was characterised by small number of depressions scattered throughout the site. In this locality dominated the plants of minor competitive abilities (like Lathyrus pratensis L., Lotus corniculatus L. and others). The spatial pattern of populations was described on the basis of the locations of all ramet clusters in 100 m[^2] square plots. Each ramet cluster was attributed to a developmental stage. The differences in height of ramets between stages was estimated on the basis of lenght of the tallest leaf and generative shoot measured in all genets and ramet clusters in both populations (30 leaves and all generative shoots in 5 clusters of ramet at generative and senile stages and 4 - at fragmentation phase in both populations). In study year 2000 Iris sibirica population in LW locality was consisted of 26 ramet clusters and showed an aggregation structure, while population growing in MW site was consisted of 502 ramet clusters and presented the group-aggregation spatial structure constituted by groups of dozen or so ramet clusters, forming large aggregations. Both populations showed signs of senility in effect of absence of genets in prereproductive stages. In 2001 and 2002 the seedlings and juvenile genets appeared only in artificially made gaps. The genets in initial stage are much lower (about 40 %) than older ones and the ramet in MW locality reached greather height (6 to 23%) than in LW site. The evaluation of structure of populations taken as indicator of their vitality, show that the population from less wet locality was in better condition despite of low abundance. Domination of ramet cluster at generative stage and vicinity of plants with low competitive potential enables longer existence of Iris sibirica in occupied site. In more wet locality the I. sibirica population is worse equiped to survive. Advanced senility and the vicinity of plants with high competitive potential might inhibit the proliferation of I. sibirica ramet clusters, accelerate their fragmentation or even eliminate from occupied site.