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In this study, eight forest associations in Szczecin Landscape Park and in the vicinity were examined for the presence of ant species. The only species present in all the associations was Myrmica ruginodis. Habitat conditions in the beech forest (Galio odorati-Fagetum), which grows on post-glacial hills, was diversified enough to enable occurrence of as many as 16 ant species. There was no substantial difference in ant species composition between beech and mixed forests. Alder swamps and riparian forests seemed to provide unfavourable living conditions for ants and only 3 ant species were recorded in these environments. Results show that indicating the type of plant association alone may be insufficient to characterize the environmental conditions that affect ant occurrence.
A phytosociological classifi cation and the characteristics of weed communities developing in root crops of the Kałuszyńska Upland are given in this paper. The presence of three associations: Digitarietum ischaemi, Echinochloo-Setarietum and Lamio-Veronicetum politae, as well as of two communities: Setaria pumila–Setaria viridis and Panico-Setarion alliance, has been found. The differentiation in trophic and soil moisture conditions of habitats results in the fl oristic diversity of communities, divided into lower phytosociological units. Two variants have been distinguished within the association Digitarietum ischaemi, whereas Echinochloo-Setarietum has been divided into 2 subassociations and 6 variants.
Acta Agrobotanica
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2001
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tom 54
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nr 1
153-161
This paper reports new stands of subatlantic Spergulo-Chrysanthemetum segeti association, found on the Olsztyn Lake District area. This association is very seldom described from Poland. It occurs in spring crops and root crops cultivations. The most important attributes of this association are: a mass occurrence of Chrysanthemum segetum, a numerous occurrence of Spergula arvensis, a big contribution of Centauretalia cyani species and habitat's humidity, indicated in the presence of numerous hygrophytes. Communities of this association found on Olsztyn Lake District are similar to the other Sperglllo-Chrysanthemetllm segeti phytocoenoses, described from the other regions of Poland. However, they show alittle differences too. The most important of them are: very smali participation of Eu-Polygono-Chenopodion species and the absence of Panico-Setarion species, general floristic scantiness and smali participation of Chrysanthemum segetum and Spergllla arvensis in the most of records. Spergulo-Chrysanthemetum segeti communities occur very seldom in the central part of the Olsztyn Lake District and they are probably the farthest advanced to the east, known stands of this association in Poland.
The aim of the present study was to describe the distribution of xerothermic species of vascular plants in the lower San River valley and the relationship between their density and the intensity of selected environmental (natural and anthropogenic) factors. Xerothermic species occurred more frequently in the present valley floor compared to the glacial terrace. Within the present valley, the highest density was observed in the floodplain. The examined species also occurred more often on steep slopes of the valley, at the margins of the present valley terraces, and in the area of occurrence of aeolian sands. Moreover, a positive correlation has been found between the number of xerothermic species and the area of polyhemeroby ecosystems. The distribution of xero- and thermophilous species is determined by natural edaphic and geomorphological factors as well as anthropogenic ones (land use, lowering of the groundwater level as a result of river regulation).
The characteristics of communities found in unploughed stubble fields of the Mazowiecki Landscape Park and its agricultural buffer zone are presented in the paper. The association Echinochloo-Setarietum divided into a typical variant, the variant with Galinsoga parviflora, and the variant with Bidens tripartite, was the most frequently noted and floristically differentiated association. Patches of Digitarietum ischaemi were also frequently observed in stubble fields on the poorest habitats. Rarely, on fertile soils, small patches of floristically rich communities with Veronica agrestis were recorded. Periodically, excessively wet habitats were seldom occupied by the speciesrichest phytocoenoses of Centunculo-Anthoceretum punctati. Single patches of the community with Setaria pumila, the form with Aphanes arvensis, were observed only in the south-eastern part of the Park.
The aim of this paper is to assess usefulness of different measures when determining central tendencies which characterise the environmental requirements of living organisms. Mathematical analyses were made of the environmental parameters of river macrophyte communities which were taken as a representative pattern of different levels of biological structures. To deliver a representative dataset, botanical surveys were carried out on a range of British rivers together with environmental assessment and the plant communities groups were identified based on characteristic species according to eslished phytosociological criteria. The mean values and standard univariate medians of the revealed associations were compared with means calculated on the basis of advanced transformation and also with the rarely calculated multivariate L median. Due to high variance and asymmetrical distribution, the analyses based on the mean-value appeared to be limited in application. To avoid this disadvantage transformation to obtain normality of the dataset standardisation was proposed although even this did not fully reach a satisfactory symmetry. It was concluded that each environmental variable for each single biota must be individually treated by a suile transformation to obtain approximately normal distributions. The univariate median was very resistant to the effects of outliers but gave a flattened output of the environmental dataset making the partitioning of biological units very difficult. The multivariate L median appeared to be unaffected by outliers. It enabled to obtain considerable ordering of communities against individual environmental parameters without data transformation.
The study presents the structure and floristic composition of mixed fir forest at the northern range limit of European silver fir (Abies alba) in Poland. Phytosociological data were collected in the forest reserve “Murowaniec”,which was established to protect mixed forest ecosystems with a large contribution of fir trees. Changes in floristic composition of these coniferous forests in the last 40 years were discussed. Protective measures are suggested in this paper, aiming at conservation of the forest ecosystems of the reserve.
Typhetum laxmannii (Ubrizsy 1961) Nedelcu 1968 is a plant association new to Poland, built by an expansive kenophyte - Typha laxmannii Lepech. This paper presents the general distribution of both, the species and the association, paying particular attention to the area of Europe and Poland where, in recent years, many new locations as well as an increasing participation in vegetation cover have been observed. The habitat preferences of Typhetum laxmannii, the floristic composition of the association and its geographical differentiation within the occupied area are described. The current distribution of the association in Poland is presented on the cartogram map 10x10 km and possible expansion routes are suggested.
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