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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.

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Variation and correlations of leaf traits of two Taxus species with different shade tolerance along the light gradient

Liu W., Li S., Su L., Su J.

Polish Journal of Ecology

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2013

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Vol. 61, nr 2

329--339

EN

The variations in leaf traits of Taxus species in different light conditions are still poorly understood. We sampled leaves of Taxus yunnanensis W. C. Chang L. K. Fu and Taxus chinensis var. mairei (Lemée and Lév.) W. C. Cheng and L. K. Fu along an illumination gradient (full daylight, 40–60% full daylight, <10% full daylight), and analyzed how seven leaf traits and their correlations changed under different light conditions. The leaf trait that showed the greatest variation was specific leaf area (SLA) for T. yunnanensis, followed by leaf dry mass (LM) for both taxa. The smallest variation was in leaf width (LW) for both taxa. Plasticities of all leaf traits in both taxa were higher than 50%, and those of leaf area (LA), LM and SLA were greater than 80%. The light gradient was positively correlated with leaf length (LL), LM, leaf dry matter content (LDMC), and leaf length to width ratio (LWR). LW and SLA were negatively correlated with the light gradient. Analyses of relationships among leaf traits showed that LM of T. yunnanensis, T. chinensis var. mairei and both taxa was positively correlated with LL, LW, LA, LDMC, and LWR, and negatively correlated with SLA under all light conditions. We concluded that leaf traits and their relationships were affected by light conditions.

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Success and failure of endangered tree species : low temperatures and low light availability affect survival and growth of European yew (Taxus baccata L.) seedlings

Iszkuło G.

Polish Journal of Ecology

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2010

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Vol. 58, nr 2

259-271

EN

European yew (Taxus baccata) is a rare and endangered species in many European countries. Observations of high levels of T. baccata seedling mortality under the canopy of mature trees suggest that mortality due to low irradiance may contribute to the decreasing population size of this species. The primary goal of my work was to determine if light and nitrogen fertilization influence the growth and survival of T. baccata seedlings. In 2002 and 2003, we carried out a field experiment with a range of light availabilities (reducing artificial light and obtained 2, 8, 30 and 100% RPPFD-Relative Photosynthetic Photon Flux Density) and a nitrogen fertilization treatment (with and without NH4NO3 fertilizer). In 2002 and 2003, the mortality of one-yearold seedlings was very high after the first winter, especially within extreme light conditions (2 and 100% RPPFD). Biomass of seedlings was highest in 30%, intermediate in 100% and lowest in 8% and 2% RPPFD. High levels of seedling mortality during the winter suggest that low temperatures were the primary determinant of T. baccata seedling survival. Nitrogen fertilization only had a positive effect on growth in higher RPPFD values (8, 30 and 100%). Both total needle mass and needle mass allocation were higher in the nitrogen fertilization treatment Interaction of low temperature and light availability is probably the direct reason of high mortality of T. baccata seedlings located near the species range limit.

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Light limitation of growth in 10-year-old seedlings of Taxus baccata L. (European yew)

Iszkuło G.

Polish Journal of Ecology

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2007

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Vol. 55, nr 4

827-831

EN

Taxus baccata L. is a rare and endangered species with restricted occurrence. One or two-year-old yew seedlings occur quite frequently in natural stands of the species, but older seedlings are rare observed. Therefore we investigated the relationship between light intensity and the growth rate of ten-year-old seedlings of the European yew Taxus baccata (L.). The study was conducted in a preservation area established in 1999 in order to protect the gene pool of the 'Cisy Staropolskie' Reserve in the Bory Tucholskie Forest (northern Poland). A total of 570 three-year-old seedlings were planted under the canopy of a 45-years-old forest stand composed of oak (50%), birch (40%) and hornbeam (10%). Measurements of seedling heights were taken in 1999, 2003 and 2005. In 2005, the current annual growth increment was measured. Relative Photosynthetic Photon Flux Density (RPPFD) up to 30% had a positive influence on the height and annual height increment of the yews, but most of individuals grew below 5% RPPFD. This suggests that increasing light level would increase growth of yew in both natural recruitment and planting.

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Restytucja cisa pospolitego (taxus baccata l.) w Nadleśnictwie Kaliska

Frydel K.

Inżynieria Ekologiczna

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2005

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Nr 12

184-186