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1

Cadmium and Lead Accumulation Patterns in Organs of Chosen Urban Tree Species

Steindor K., Palowski B.

Ecological Chemistry and Engineering. A

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2011

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Vol. 18, nr 3

453-460

EN

The concentration of Cd and Pb in leaves/needles, twigs, seeds and fruit coverings of: horse-chestnut (Aesculus hippocastanum L.), yew-tree (Taxus baccata L.), European ash (Fraxinus excelsior L.), and in the soil at the base of the same trees was investigated. The ability of metal accumulation was determined in all investigated tree species as well as different partitioning in examined plant tissues. The lowest Pb concentration was found in fruit parts of all tree species: in seeds or fruit covering. The lowest Cd concentration in unpolluted regions was determined in leaves/needles or twigs. The highest Cd and Pb concentration in investigated tissues depends on the species and the pollution level of the place where plants were growing. The obtained results could be used to determine the most suitable organs for Pb and Cd biomonitoring in the environment.

PL

Oznaczono stężenie Cd i Pb w liściach, pędach, nasionach oraz częoeci płonej owocu trzech gatunków drzew popularnie nasadzanych w miastach: kasztanowcu zwyczajnym (Aesculus hippocastanum L.), cisie pospolitym (Taxus baccata L.) i jesionie wyniosłym (Fraxinus excelsior L.) oraz w materiale glebowym zebranym pod wybranymi osobnikami. Stwierdzono zdolność do akumulacji metali przez badane gatunki oraz zróżnicowane stężenie metali w poszczególnych organach. Najniższe stężenie Pb oznaczono u wszystkich trzech badanych gatunków w częściach owocu – nasionach lub części płonej, w przypadku Cd dla drzew z rejonów stosunkowo słabo zanieczyszczonych niższe zawartości kadmu notowano w liściach/szpilkach lub pędach. Organy o najwyższym stopniu koncentracji Cd i Pb w tkankach różnią się w zależności od gatunku drzewa, badanego metalu oraz stopnia zanieczyszczenia środowiska, z którego pobierano próbki. Uzyskane dane mogą posłużyć do wytypowania organów przydatnych w biomonitoringu kadmu i ołowiu w środowisku.

2

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.

3

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.

4

Changes of population structure of Taxus baccata L. during 25 years in protected area (Carpathians, Western Ukraine)

Iszkuło G., Boratyński A., Didukh Y., Romashenko K., Pryazhko N.

Polish Journal of Ecology

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2005

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Vol. 53, nr 1

13-23

EN

The aim of the study was to assess the present state of the Taxus baccata L. population in the Knyazhdvir Nature Reserve (West Ukraine) and to analyse the population structure changes that had occured during 25 years. We found the tendency towards population ageing but with relatively numerous young individuals and seedlings. Surprisingly, specimens with bi- or trifurcate trunks (polycormic) were significantly thicker than those with single trunks (monocormic). This attest to some kind of dominance of polycormic specimens over monocormic ones.