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1

Floristic and ecological differentiation of the association Calamagrostio villosae-Pinetum Staszkiewicz 1958 in Poland

100%
Cabala S., Sliwinska-Wyrzychowska A.
Seria Biologiczna. Uniwersytet im. Adama Mickiewicza w Poznaniu
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2004
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tom 69
2
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Content available

Morphological variability of leaves of Sorbus domestica L. in Croatia

84%
Poljak I., Kajba D., Ljubic I., Idzojtic M.
Acta Societatis Botanicorum Poloniae
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2015
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tom 84
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nr 2
The paper studies the morphological variability of the service tree populations in the continental and Mediterranean regions of Croatia. The inter- and intra-population variability, as well as eco-geographic population differentiation, was established on the basis of eight measured morphological characteristics of two types of leaflets (lateral and terminal) and two derived ratios, using descriptive and multivariate statistical methods. The conducted research established a high variability of morphological characteristics. In comparison with lateral leaflets, terminal leaflets showed a higher degree of variability for the majority of the studied variables. The differences between the trees within populations, as well as the differences between populations, were confirmed for all studied characteristics. The study also confirmed a trend of population variations according to the eco-geographic principle. Populations from climatically different and geographically distant habitats, in other words from the Mediterranean and the continental region, differed in the majority of studied characteristics. In addition to the established pattern of ecotypical variability between the continental and the Mediterranean regions, the clinal variability with regard to altitude and mean annual temperature was also confirmed. Small, although statistically significant clinal variability with regard to the longitude was recorded for two measured characteristics. The conducted study provided insights into the variability of the service tree populations in Croatia, which is a basis for further research that should be implemented in order to produce guidelines for the breeding and conservation of genetic resources of this rare and endangered noble hardwood species.
3

Can reed stands be good indicators of environmental conditions of the lake littoral? A synecological investigation of Phragmites australis - dominated phytocoenoses

84%
Pelechaty M.
Polish Journal of Environmental Studies
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2004
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tom 13
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nr 2
A comparative analysis of three regional groups of phytocoenoses dominated by Phragmites australis was undertaken in order to find if they reveal any interregional differentiation in the habitat (water and substratum) conditions and if the differences are followed by floristic composition. A group of 60 phytocoenoses studied in mesotrophic and (mostly) eutrophic lakes of midwestern Poland were compared to two groups investigated in moderately nutrient-rich lakes of northeastern Poland (32 phytocoenoses) and nutrient-poor lakes of northern Poland (20 phytocoenoses). Statistical analyses revealed significant habitat differences. Although the groups of phytocoenoses were studied in different regions and different types of water bodies, they occupied habitats poor in bioavailable forms of nutrients in water and organic matter content and sodium in the substratum, which is inconsistent with the general opinion concerning the reed community as indicative for the high trophy level of lakes. Floristic differences among the studied groups of phytocoenoses are not significant in phytocoenotic terms and relate more to the type of lakes than to established habitat differences. This might suggest that the habitat-forming power of Phragmites australis is the main factor to influence habitat properties.
4

Ecological differences between two sympatric species of armadillos [Xenarthra, Mammalia] in a temperate region of Argentina

67%
Abba A. M., Cassini M. H.
Acta Theriologica
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2010
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tom 55
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nr 1
35-44
Morpho-physiological specialization related to foraging can act as constraints on behaviour and ecological patterns of abundance and distribution. We tested this prediction in two species (weeping or screaming hairy armadillos Chaetophractus vellerosus Gray, 1865 and mulitas Dasypus hybridus Desmarest, 1804) that represent the two subfamilies of armadillos (Dasypodidae, Xenarthra): Euphractinae and Dasypodinae. The first subfamily possesses a well-developed masticatory apparatus that is considered primitive within the Xenarthra, while Dasypodinae show reductions in various aspects of cranial morphology. We sampled signs (burrows and foraging holes) and captured both species on 34 farms randomly selected in the north-eastern Pampas region of Argentina. We analyzed several niche dimensions. The two species showed significant differences in habitat use, seasonal patterns and diet. Weeping armadillos were generalists in their diet and active throughout the year. They were associated with calcareous-sand soil, as expected for a burrowing animal of the deserts. They tolerated a wide range of environmental conditions. We found that mulitas are myrmecophagous, and that they demonstrated a reduction in body temperature and activity during the cold season. As expected from their geographical distribution, mulitas used mainly vegetation with high cover and were associated with humic soils. Niche segregation between the two species of armadillos appeared to originate from different degrees of dietary specialization.
5
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Dendroecological differences between Taxus baccata males and females in comparison with monoecious Abies alba

67%
Iszkulo G., Jasinska A. K., Sobierajska K.
Dendrobiology
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2011
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tom 65
Taxus baccata L. is a rare and endangered dioecious species in Europe. Species of this mating system are considered to be the most vulnerable to extinction. It is believed that one reason for this state may be the uneven reproductive effort and different habitat requirements of the two sexes. Silver fir and European yew have very similar ecological requirements, but fir is a monoecious species. The aim of this study was to compare the growth rate andthe effect of precipitation andtemperature on the annual tree-ring width of silver fir and both sexes of European yew. The study site was the Knyazhdvir reserve in western Ukraine, located near the limit of the geographical range of both species. Knyazhdvir reserve is the site of one of the last yew populations in Europe with a large number of individuals (about 15,000 individuals above 1.3 m height) growing alongside fir.Woodsamples were taken from 15 male and15 female specimens of T. baccata andfrom 15 specimens of A. alba and were subjected to a standard dendrochronological procedure. The results showed high positive correlation between the temperatures in February andMarch andthe tree-ring width in the studied species and genders. The response of annual tree-ring width to the examined climatic factors was relatively similar in yew andfir. However slight differences were foundbetween males andfemales of T. baccata. The growth rate decreased more rapidly in females compared to males, probably following sexual maturation. Precipitation in April hada positive effect on firs andfemale yews, but not on male yews. This confirms earlier reports of the requirement of female specimens of dioecious species for a higher humidity than male individuals.
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