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The available phytosociological data and original observations were used for preparing a list of plant communities with Sorbus torminalis on its natural sites in Poland. The community context of its sites showed a wide range: from pine-oak forests (alliance Dicrano-Pinion) and oak forests (Quercetalia robori-petraeae, Quercetalia pubescenti-petraeae) to oak-hornbeam forests (Carpinion) and beech forests (Fagion). Oak-hornbeam forests (Carpinion) are the most frequent communities with S. torminalis in Poland. Despite this, oak forests (especially the open thermophilous forests of Quercetalia pubescenti-petraeae) seem to be the most suitable sites for growth and reproduction of this light-demanding tree species. Some remarks on S. torminalis conservation in the community context were also presented as its passive protection in some forest reserves has proved to be ineffective or even harmful.
Praca przedstawia historię, a przede wszystkim obecne formy ochrony jarzębu brekinii Sorbus torminalis w Polsce. Wskazano w niej przeszłe i obecne zagrożenia dla gatunku oraz przeanalizowano skuteczność dotychczas stosowanych form ochrony. Zwrócono uwagę na konieczność zmiany podejścia do ochrony tego gatunku w Polsce
The results of the study on morphological variation of fruits and seeds of a rare forest tree species Sorbus torminalis (L.) Crantz in Poland are presented and discussed. The ripe fruits were collected from 13 localities widespread within the range of the species. Fruits and seeds were measured according to 13 morphological traits. The biometric data were subjected to multivariate statistical analysis in attempt to define intra and inter populational variation. Most of the fruit and seed traits are significantly correlated and are characterized by moderate level of variation. Traits describing size and shape are higher variable in seeds than in fruits. High level of variation within examined populations was ascertained. The average among population component of variation was only 23.99%. Though the differences between sampled populations are significant, almost no geographical pattern of this differentiation was detected. The biological significance of some of fruit and seed features is discussed in the paper. Examining the collected material a single fruits with 5–6 seeds were found what suggests the presence of three carpels in gynoeceum, a number not previously reported in the species.
In the present paper ecological organization and environmental conditions of Lilium martagon L. population in Forestry Bieniszew near Konin are studied and described.
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The paper presents the proposal of a strategy of conservation of genetic resources of wild service tree (Sorbus torminalis) in Polish forests. Some results of the recent studies on distribution, resources and genetic variability of wild service tree in Poland that make a scientific base of the programme are presented. Both in situ and ex situ methods should be applied in conservation of genetic resources of S. torminalis. Conservation affords should first to be focused on forest management oriented in favor of wild service tree (e.g. logging intervention, competition control, preparing of favorable sites for new establishments). Further, in situ measures should include selection of conservation areas (natural gene reserves) and preserving trees of the best quality (protected genotypes). These objects would provide seeds for new establishments and to feed populations of small size. The genotypes of the selected earlier preserving trees (about 250–300) would be protected in ex situ conservation objects – seedling and clonal seed orchards. These plantations would also provide seeds needed for future establishments. The genotypes of endangered populations or single trees of S. torminalis could be preserved in the Forest Gene Bank in Kostrzyca.
In the present paper ecological organization and environmental conditions of N. nidus-avis population from nature reserve ‘Sokółki’ near Konin is studied and described.
This paper presents the results of the study on morphological variability of leaves of a scattered tree species Sorbus torminalis (L.) Crantz) in Poland. The leaves from short- and long shoots were collected from 17 localities widespread within the range of the species in Poland. Leaves were measured according to 15 morphological traits. The biometric data were subjected to multivariate statistical analysis in attempt to define variability between local populations. Most of the leaf traits are significantly correlated and are characterised by moderate level of variation. The average among population component of variation was 32.82% and 27.46% for leaves on short- and long shoots, respectively. The differences between sampled populations are significant, but only a weak geographical pattern of this differentiation was detected. Clinal type of variation was ascertained in two traits. Leaf traits which discriminate best the studied populations are also indicated. It was proved that leaves on short shoots differ markedly in shape and size from those of long shoots. Leaves on long shoots are steadier, but morphological trait values are less correlated. The study also confirmed the occurrence of individuals with leaves characteristic for S. torminalis var. perincisa Borbas et Feck and S. torminalis f. mollis Beck in a few Polish populations.
This paper presents current distribution and resources of Sorbus torminalis (L.) Crantz in Poland. Seventy three natural localities of the species are listed and described. Total resources of S. torminalis trees in Poland are estimated to be about 2550.
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