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EN
The characteristic of Pinus uncinata on the basis of biometrical analyses of 16 cone features was done. The research was based on 8 samples representing 6 populations, consisting of 50 cones each, collected in the Pyrenees, within the natural range of the species. All the investigated cone features were moderately differentiated, with the variation coefficient ranging from 8 to 30%. The particular populations differ significantly from each other statistically according to several features examined. The samples collected in the same population also vary significantly. The differences between populations, however, do not enable their division into groups, which supports their origination from the same Pleistocene refugia.
EN
Dryas octopetala is an important arctic alpine species, but its morphological analyses are scarce. The study deals with present European biogeographical structure based on morphology and its relations to the phylogenetic structure and the climate. Characters of leaves from 23 isolated populations were measured, statistically characterized and analyzed with the use of ANOVA and the discriminant analysis. All the features differentiated the tested samples significantly. Differences between plants representing regions were greater than between the samples within regions with regard to the four characters. The most visible division ran between the samples coming from the southern and the northern parts of the range, with the sample from the Western Scandinavia occupying the central position. Correlations between characters and climactic factors were shown, and the size of the leaf was associated mainly with the minimum temperatures of spring months, while the leaf shape with the rainfall during the summer months. Characters differentiating the regions and discriminating populations strongly were mostly dependent on the influence of the climate. The results of the present study were not fully consistent with the outcomes of the biogeographic molecular analyses of the researched species. Some parallels can be drawn when comparing the present analyses with the geographic differentiation of two other arctic-alpine shrubs Salix herbacea and S. reticulata. Although morphological diversity of Dryas octopetala showed a geographic structure, it was most probably shaped mainly by the influence of the environmental and climatic factors.
EN
The goal of the study was to check if the shape-describing characters, calculated as ratios of the morphological measured traits are more stable, compared to the latter, and can be treated as independent on environmental conditions. The test was based on the example of leaves of Salix herbacea and Betula nana. The individuals of the two populations of S. herbacea from Tatra Mts. were divided into two groups: with bigger and smaller leaves. The two populations of B. nana came from different substrata: the first one, collected from the mire on the lower altitude, had bigger leaves, and the second, collected from the granite plateau and higher altitude, had smaller leaves. For both species, the measured traits were generally more variable than the ratios calculated on their basis, as expressed by the variation coefficients. The results of Students' t-test analyses showed statistically significant differences between the two groups of S. herbacea and the two populations of B. nana with respect to almost all the measured characters, and no such differences for the calculated traits, reflecting the leaf shape. As the differentiation of the leaf size was probably bound to the environmental factors, the lack of the dependence of the leaf shape on the leaf size could lead to a conclusion of independence of the leaf shape on the environment conditions.
EN
The paper uses statistical methods to examine whether origination from different Pleistocene centers influences the present-day variation of Carpinus betulus in Poland. Twenty-nine populations of the species were sampled in communities of the Carpinion betuli alliance in most of the country. Samples of 100 involucres for each population were analyzed for 26 morphological characters. Despite the rather accidental similarities among the sampled populations, their geographic variation confirmed their origin from at least two different refugia, southeast and west.
EN
The subalpine communities of Pinus mugo were destructed and replaced by pasture lands on plateau parts and moderately inclined slopes of the mountains during between the 15th andthe 18th centuries. The species were able to survive that pressure probably on the abrupt slopes of the glacial cirques. The pasturing stoppedin the 19th century, andthe mountain pine startedto reforest its previous habitats since that time. It was also plantedin several places andsome of contemporary populations can origin from the seeds of the Giant Mountains. In the latter case the populations on the plateau shall reveal differences in the cone characters from autochtonous ones from the glacial cirques. This study was structured on this hypothesis. The characteristics of seven Pinus mugo populations in the Giant Mts. were comparedon the basis of 15 morphological characters of cones. Each population was represented by at least 30 individuals, and for every individual 10 cones were examined. Four of the sampled populations, treated as local, occurred on the steep slopes of the glacial cirques andthe other three on the mountain plateaus, usedas pastures in the 17th to 18th centuries, potentially originatedfrom another region. Results show rather small differences among the comparedpopula - tions, independently of origin. The separation of the plateau from the steep slope ones is rather inconspicuous, if any. This suggests the local origin of plateau populations, even when planted.
EN
Cones of Pinus uliginosa from the "Torfowisko pod Węglińcem" reserve were tested biometrically, on the basis of 16 characters.The obtained data were statistically analysed.The cone scale width, the ratio of cone length/width and the maximal diameter of cone were the most stable, while the cone scale thickness and the ratio of cone scale length/thickness were the most variable of the cone characters.The intrapopulational differentiation was not big.The examined pine species has cones with characters which are intermediate between Pinus sylvestris, P. mugo and P. uncinata.
EN
The intra- and interpopulational geographic variation of three distant populations of J. oxycedrus subsp. macrocarpa was examined biometrically on the basis of morphological key-characters of needles, seeds and cones. The shortest Euclidean distances were used in the agglomerative grouping of closest neighbourhood and discrimination analysis with principal component analysis (PCA) was performed to verify the south-north differentiation of the taxon in Italy. Most of the cone and seed dimensional characters are correlated. No significant correlations were found between cone and needle characters. The sampled populations differ only insignificantly from one another, while the intrapopulational variation is slightly higher. Cone length as well as seed number, width and thickness were significantly correlated with geographic latitude, while the other four characters are not. Differences in cone shape were observed between individuals, so that several morphotypes can be distinguished.
EN
Hybridisation and introgression are expected to be common in plant populations composed of various species of the same genera. These processes, however, frequently have one direction or are asymmetric, when one of hybridising species is a donor and other recipient of pollen. The asymmetric hybridisation may be also an important manner of migration by pollen. According to the theory of asymmetric hybridisation in mixed oak populations of European white oaks (Quercus robur and Q. petraea) the number of hybrid saplings should be higher under a canopy of Q. robur than under Q. petraea trees. The aim of this study was to determine, which of the two species in the mixed populations has a greater degree of success in regeneration and colonization, measured by the proportion and density of saplings and young individuals higher than 0.3 m. The taxonomic composition of saplings under the crown ranges of trees was analyzed on the basis of morphological characters of leaves in two distantly located mixed oak stands in Poland, in Jamy and Legnica Forests, where young generation to about 17-18 years old was observed under canopy of 125-140 years old mother trees. The first population is located about 100 km of Q. petraea geographic range and covers area of 6 km, the second about 500 km of Q. petraea range and covers more than 10 hectares. The density of 60 and 134 adult trees per hectare, were found in analysed populations, respectively. A significantly higher proportions of Q. petraea than Q. robur saplings were found in both compared stands. A hybrid saplings proportion were higher than hybrid adult trees. The hybrid saplings were observed more frequently under canopy of Q. robur only in the stand closer to the range of Q. petrea. Gene flow from Q. petraea to Q. robur by cross-pollination was found to be likely. The number of hybrid saplings found under crown projections of Q. petraea trees in both populations suggested also reverse gene flow, at least in the stand located close to the north-eastern limit of the Q. petraea range. A higher regeneration success of Q. petraea was observed in both stands suggesting expansion of this species.
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