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Wood density in European larch (Larix decidua Mill.) from selected provenances grown at the Siemianice Forest Experimental Station

Szaban Jarosław, Kowalkowski Wojciech, Łacka Agnieszka, Karaszewski Zbigniew

Drewno : prace naukowe, doniesienia, komunikaty

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2021

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vol. 64, nr 207

27--41

EN

The purpose of this study was to determine variation in the density of wood from different provenances, growing under the same soil and climate conditions. Samples were obtained from an experimental site located at the Siemianice Forest Experimental Station. We analyzed larch wood samples from trees aged 48 years, collected from six different provenances in Poland. Diameter at breast height (DBH) and tree height were used to calculate the parameters for sample trees, from which a 70 cm segment was cut, from breast height upwards (up to 2 m of tree height). Samples with dimensions 20 × 20 × 30 mm were obtained from the material. Sample volume was determined by stereometry. Relative density was determined for 890 samples. The highest wood density was found in trees from Czerniejewo, and the lowest in trees from Rawa Mazowiecka. Analysis of variance, including the mean wood density values of trees, did not demonstrate significant differences between provenances in terms of this characteristic. Mean relative density was higher in larch wood samples from the heartwood zone. The density of samples cut closer to the bark was lower, as the value was affected by the large content of sapwood. A relation was found between the provenances from which the study material was sourced and the relative density of wood.

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Does the genetic variability of Phragmites australis (Cav.) Trin. ex Steud determine the spatial distribution of the species?

Świerk D., Krzyżaniak M., Kosiada T., Urbański P., Behnke-Borowczyk J.

Oceanological and Hydrobiological Studies

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2018

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Vol. 47, No. 4

405--414

EN

This paper is an attempt to answer the question whether common reed specimens growing in a particular habitat are genetically related. We have tried to identify groups of plants homogeneous in terms of habitat requirements and genetic similarity. Our objective was also to answer the question whether habitat conditions can affect the morphological characteristics of plants. Plants and bottom sediments were collected from 40 sites in central Poland, which differ in soil moisture and the degree of urbanization. Our research and analysis confirm the hypothesis to a certain extent. During the study, we identified three groups of plants homogeneous in terms of habitat and genetic factors (CVA model), which constitute 20% of all examined plants. In our opinion, further research is required on a larger population of P. australis in a larger area. The research revealed that plants growing in moist and wet areas were characterized by higher content of chlorophyll in leaves, longer stems as well as thicker and wider laminae. The common reed plants preferred anthropogenic substrates, which did not contain many nutrients, but were abundant in calcium. Our study confirmed the high tolerance of P. australis to soil salinity.

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The effect of the ploidy level and genetic background of Sphagnum denticulatum on its morphology and ecological requirements

Melosik I.

Oceanological and Hydrobiological Studies

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2009

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Vol. 38, No.4

153-164

EN

This paper presents a current study on the morphology, genetic variability, and ecological requirements of the gametophytically diploid S. denticulatum (Bryophyta, Sphagnaceae). Its broad variations in morphology and physiology, coupled with its low genetic variability, may be explained by epigenetic remodeling in response to environmental heterogeneity. Phenotypes initiated via a plastic response can be canalized in the stable and predictable conditions on the bottom of Lobelia lakes. The problem of the different development of these isolated populations is a matter for further taxonomic studies and discussion. Taking into account the great physiological tolerance and massive development of S. denticulatum, predominantly in man-made and man-modified habitats, the question arises: how far should we go to protect this species? This is particularly important at sites where it threatens the survival of other protected plants.