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A total of 1279 field-collected Ixodes ricinus ticks were screened for Borrelia burgdorferi sensu lato (s.l.) in a natural and an urban ecosystem of Ostrava city (Czech Republic) by using molecular methods. Minimal prevalence rate for Borrelia burgdorferi s.l. in ticks for the urban park Bělský les was found to be 13.8% (17.6% in males, 17.8% in females and 11.7% in nymphs), similarly for the natural site Proskovice was minimal prevalence 15% (12.5% in males, 20% in females and 14.9% in nymphs). Six proven human pathogenic genomic species have been recorded in the study: B. afzelii, B. garinii, B. burgdorferi s.s., B. valaisiana, B. lusitaniae, and B. spielmanii. Emerging B. spielmanii was detected for the first time in Ixodes ricinus ticks in the region. Our results highlight the need for surveillance of zoonotic tick-borne pathogens even in urban areas.
Solidago species are one of the most widespread invasive species in Europe. In Central Europe, vegetation dominated by alien goldenrods can occupy vast areas. Their presence causes a decrease in the biodiversity level of numerous groups of organisms (plants, birds and insects). Alien Solidago also disturb biogeochemical cycles, as well as the primary productivity in infested ecosystems. In Central Europe, four alien Solidago species are considered as naturalized plants: late goldenrod (Solidago altissima L.), Canadian goldenrod (S. canadensis L.), tall goldenrod (S. gigantea Aiton), and grass-leaved goldenrod (S. graminifolia (L.) Elliot. = Euthamia graminifolia (L.) Nutt.). To analyse the dynamics of the growth and flowering of Solidago species, an experiment was conducted in which the goldenrods were planted in pots. We examined the life history traits, which are treated as being strongly connected with the invasive abilities of these species. The height, number of ramets and percentage of flowered plants were noted at ten-day intervals from May to November over a period of four years. Two native species, often co-occurring with alien goldenrods, were analysed for comparison: European goldenrod (Solidago virgaurea L.) and common tansy (Tanacetum vulgare L.). The analysed species reached their maximal height during the second and third years of the experiment. The highest ramets were noted in the case of Solidago altissima, S. canadensis and S. gigantea. A group of lower plants consisted of Solidago graminifolia, together with the native species S. virgaurea and T. vulgare. The number of ramets formed by S. graminifolia was more than two times larger than in the case of other species. All of the analysed species flowered during the time of observation but, grass-leaved goldenrod, was the only one among the alien species which flowered in all pots and 100% of individuals produced mature seeds. Its phenology (early flowering and seed ripening) was more similar to native species’ than to other alien Solidago. Our results suggest Solidago graminifolia has strong competitive abilities; however, its range is very limited. The reasons for the slow spread of this species in Europe – other than competitive limitations – should be considered.
The investigations concerned sites of Acer platanoides L. infected or not by Rhytisma aceriniu (Pers.) Fr. The aim of the study was to check the occurrence of R. acerinium, and whether it reflects the environmental status. Furthermore, an analysis was carried out to find out whether the applied SOFM offers additional advantages to solve problems in relation to conventional methods. Concentrations of selected elements in soils and leaves, and leaf and "tar-spot" morphometric traits were also measured. A significant differentiation was found between sites in relation to the analyzed traits. It appeared, that sites showing lower concentrations of chemical elements and proper developmental habitat conditions massive infections take place. The study showed that R. acerinium is a good biological indicator for assessment of environmental status. The applied, conventional statistical methods, SOFM and image techniques showed similar, but not identical results for assessment of environmental quality using R. acerinium. SOFM appeared to be more useful for ordination of results and ought to be taken into account as a proper tool of estimation of various plants and their biotopes.
Natural forest fires are considered as a part of natural ecosystem processes. Short-term effects of prescribed fire on densities and taxonomic diversity of soil Acari were studied in fresh pine mixed forest (“Biala” forest ) in the Mazovia region, Central-Eastern Poland. Three plots (size 1 m²) of similar soil type and vegetation were selected for prescribed burning. Soil samples of an area of 10 cm² and the depth of 5 cm were collected in June 2005 – one day after the burning, 60 days after the burning and 90 days after the burning. Samples were collected from within the border of the burned plots, from the border itself, as well as from the surroundings. Due to the burning, the density of Acari communities decreased from 11.5 × 10³ ind. m⁻² recorded in the surroundings to 3.2 × 10³ ind. m⁻² recorded in the burned plots. Values recorded within the burned plots after the fire differed significantly from those recorded on the border (P = 0.05) and in the surroundings (P = 0.0001). After 60 days, an increase in Acari abundance was observed in the burned plots (P = 0.02), becoming similar to that noted for the border of the plot and for the surroundings. After 90 days, there were no significant differences between the burned parts of the plots, their borders and the surroundings; however, generally decreased densities were observed, possibly due to the seasonal reason. The observed changes suggest the restoration of Acari community after disturbance.
Large-scale human-caused ecosystem disturbances may create new habitats. A good example may be long-lasting disturbances in five lakes (area from 148 to 379 ha, max. depth from 3 to 38 m) integrated into the cooling system of the power plants near Konin (52°17.8’– 52°23.3N, 18°14.4’–18°20.7’E, West Poland). In the middle of the 1990s Vallisneria spiralis began to colonize littoral zone of three of lakes and in 2002 it appeared also in fourth one. This species formed dense patches and almost completely displaced other submerged macrophytes. An aim of the study was to test a hypothesis that the appearance of rare and new for Polish fauna rotifer species might be a result of changes in littoral habitats of these lakes particularly caused by the invasion by Vallisneria spiralis. Studies were carried out in the years 2004–2006 on 3–6 littoral stations in each lake. Five-liter samples of water with macrophytes were collected from a center of macrophyte beds. Plankton (free-swimming) and epiphytic (connected with macrophyte surface) samples were elaborated separately. As many as 167 monogonont species were recorded during the three-years’ studies. From among them 6 species were new in Polish fauna. These were: Asplanchnopus hyalinus Harring, Beauchampia crucigera (Dutrochet). Lecane inopinata Harring & Myers, Lecane shieli Segers et Sanoamuang, Lecane undulata Hauer and Lepadella apsida Harring. The species are eurythermic or warm-stenothermic. Species new to the rotifer fauna of Poland were not numerous as they usually constituted less than 2% of the total density of rotifers. Thus, although the hypothesis that rare and new for Polish fauna rotifer species may appear in the littoral habitats of the heated Konin lakes was confirmed, it was also clear that the colonization of the habitats by rotifer invaders did not lead to their domination in the rotifer communities.
Techno systems release CO2 meanwhile natural ecosystems accumulate it in biomass and these flows for total techno-ecosystem stability should be in quantitative balance. General environmental stability (GES) may be described as ratio of total amount of carbon sequestered (TACS) annually by forested area of region to total amount of carbon (TACR) released on the same area from industrial sources. For Leningrad region this ratio is estimated as much as 1.15 and we may generally conclude about enough productivity of local forest ecosystems to accumulate locally released anthropogenic carbon and therefore about positive input of Leningrad region into global carbon cycle.
The spontaneous seedlings of Rhododendron luteum Sweet and Rhododendron calendulaceum (Michx.) Torr., Rhododendron maximum L., and Rhododendron japonicum Suringer were documented in Kaunas Botanical Garden of Vytautas Magnus University in 2006. More seedlings of these four rhododendron species were observed in 2007, 2008 and 2009. In 2010, altogether with aforementioned species, seedlings of Rhododendron dauricum L., Rhododendron schlippenbachii Maxim. and Rhododendron minus Michx were observed. The assessment of climatic conditions suggests that the self-regeneration of rhododendron genus plants was possibly provoked by global climate change – warmer winters and increased amount of precipitation in summers.
The study objects were 48 microhabitats of five Utricularia species in Lower and Upper Silesia (POLAND). The aim of the paper was to focus on application of the Self-Organizing Feature Map in assessment of water trophicity in Utricularia microhabitats, and to describe how SOFM can be used for the study of ecological subjects. This method was compared with the hierarchical tree plot of cluster analysis to check whether this techniques give similar results. In effect, both topological map of SOFM and dendrogram of cluster analysis show differences between Utricularia species microhabitats in respect of water quality, from eutrophic for U. vulgaris to dystrophic for U. minor and U. intermedia. The used methods give similar results and constitute a validation of the SOFM method in this type of studies.
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