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The earthworm Pontoscolex corethrurus (Müller, 1857) is reported for the first time from Punjab, India. This species was first described by German naturalist Fritz Müller in 1857 from Santa Catarina state of Brazil. It is commonly found in gardens, cropland and fallow lands. It tolerates wide range of climatic and edaphic factors due to its endogeic ecological category. P. corethrurus has high efficiency for organic matter assimilation and has ability to live in new habitat due to which it can survive even in very poor soil. The life cycle of this species is well documented and this species has economic importance due to its use in waste management.
The aim of the work was to estimate the range of morphological variability of seeds of the Himalayan balsam (Impatiens glandulifera), from different sites within Poland. It was also verified whether there was a correlation between morphological variability of seeds and type of vegetation from which they originated. Additionally, the seed coat ultrastructure of this species was studied. Biometrical analysis showed remarkable variability of seed morphology. A significant relationship between seed size and type of vegetation was also revealed. However, there was no clear relationship between seed mass and type of vegetation. Based on the structure and ornamentation of epidermal cells, the rugosely ruminate seed coat type was proposed.
River valleys are areas of transition between aquatic and terrestrial communities, with complex biological structure. As ecotones they have high biodiversity as a result of the occurrence of species with different requirements according to soil moisture. They create ecological corridors, allowing migration of the organisms in human disturbed landscape. With these migration routes, species of foreign origin which spread to a new area also benefit. Numerous alien species are considered as invasive, and described as a threat to biodiversity due to strong competitive abilities. To describe the relationships between a number of invasive species, biodiversity and size of a river, the vegetation of 750 m fragments of the Odra and Dobra river valleys on the area of the Wrocław city were analysed. The comparison of plant communities in the valley of a large, managed river (Odra) and its small tributary (Dobra) was carried out. The plant assemblages, occurring in study areas, determined the habitat conditions on the basis of Ellenberg’s indicator values (EIV’s), as well as Shannon-Wiener biodiversity index was defined. The designed sites differed according to Shannon-Wiener biodiversity index, as well as soil properties: moisture, reaction, and fertility. In the study side of the Odra river ruderal and scrub species were dominated, whereas in case of study site of the Dobra river – meadows and ruderal species. The invasive plant species occurring in the Odra valley are: Symphoricarpos albus, Solidago gigantea, S. canadensis, Robinia pseudoacacia, Clematis vitalba, Quercus rubra, Reynoutria japonica, Parthenocissus inserta and Echinocystis lobata, and in the Dobra valley: Solidago gigantea, S. canadensis. The analysis of correlation between Shannon-Wiener biodiversity index and share of invasive species revealed statistically significant influence of occurrence of invasive species on biodiversity of plant communities in case of the Odra river.
Positive correlation between seed weight and germination capacity is common for the vast majority of species. It is also known that seed weight can vary along a latitudinal gradient. The seed mass of the invasive Himalayan balsam (Impatiens glandulifera), which is native to East Asia, was examined in relation to distinct geographical regions in Poland (Bielsko-Biala: N49°52′32″, E18°57′43″; Katowice: N50°12′8.3″, E18°57′26″; Tworków: N50°01′22″, E18°15′28”); Hungary (Rum: N47°06′41″, E16°50′45″; Rábahídvég: N47°03′54″, E16°44′59″) and Germany (Halle: N51°28′47″, E11°57′12″; Marburg: N50°48′32″, E8°46′31″). The study revealed that seed mass varied both among the countries and among specific populations within Poland and Germany. In Hungary, the 50 seed lots were the lightest 0.29 g and 0.31 g in respective localities and the heaviest in single populations in Poland – 0.61 g and in Germany – 0.57 g. In the present study, populations located more southwards had the lightest seeds in contrast to the commonly encountered pattern. Higher temperature, lower precipitation and as a consequence, a shortage of water can be crucial factors that affect the seed mass of I. glandulifera. Taking into account the lower frequency and abundance of the species in Hungary, the lower seed mass may probably contribute to the limited distribution range in this region.
New records of Cercopagis pengoi (Cladocera, Crustacea) are reported for the first time from the central and western part of the Polish zone of the Baltic Sea.
We compared the habitat preferences of the alien raccoon dog Nyctereutes procyonoides (Gray, 1834) and the native badger Meles meles (Linnaeus, 1758) in two areas (Ruissalo and Tuulos) in southern Finland by radio-tracking the animals during summer from 2005 to 2008. We assumed that the habitat preferences of these two medium-sized carnivores differ to some extent (ie they are able to share the resources), because they have been sympatric for more than 50 years in southern Finland and populations of both species have increased during that period. The results indicated that the habitat preferences of these species are indeed different: raccoon dogs favoured meadows, gardens and open woodlands with tall and abundant undergrowth, whereas badgers favoured both pine forests and deciduous and mixed forests with thick canopy but sparse undergrowth. However, fields were favoured by both species in one study area (Tuulos). The results show that although both species are flexible in their habitat use and share some habitat preferences, the most favoured habitats differ between the species.
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