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Testate amoebae consist of a group of protists producing protective external coats (tests), which potentially allows them to be used in palaeoecological studies. They are known to be good indicators of several ecological parameters such as water chemistry, moisture and water table level in substrate, and especially peat moisture. Because of their strong dependence on environmental variables it is assumed that each bog microform (e.g. hummock, hollow) is characterized by a different assemblage of testate amoebae. The distribution of testate amoebae assemblages in peat bog of north-eastern Estonia was studied along the gradient from hummock to hollow in the upper 30 cm of the peat layer along a transect of 10 m. The composition and abundance of testate amoebae communities were analyzed in the samples collected (peat sampler, 5 cm diameter) from each sample point (at a distance of 2.5 m from each other) from hummock to hollow. Indicatory species specific to certain bog microforms (representing a set of environmental variables) were found, as well as other species typical for individual environment variables such as depth, peat decomposition degree, and distance to water table or local vegetation. Data analysis showed that distinct bog microforms are better described by abundance of particular testate amoebae species in peat than by species proportions in total abundance of the assemblage. The frequency of occurrence of species with dry environment preference correlates well with arboreal and Calluna vulgaris pollen and high degree of decomposition of peat; it all indicates a dryer environment and possibly is referring to a hummock microform. Amphitrema flavum correlates well with Sphagnum; this correlation increases with the A. flavum shift downwards from Sphagnum up to 4 cm. Testate amoebae assemblages in different bog microforms, even within 10 m, are distinctly different. To pay attention to possible changes of bog microforms in time is therefore crucial for reconstructing the palaeohydrological history of bogs.
Data on biology and ecology of the butterfly Oeneis jutta occurring within Poland territory are presented. Two confirmed sites of this species located in the Augustowska Primeval Forest, on a raised bog with pine tree stand and in a forest – peat bog complex are described. The only food plant for Oeneis jutta caterpillars is Eriophorum vaginatum. Adult butterflies fly c.a. six weeks, starting from the early days of May. Males appear 7-9 days before females. Peak appearance falls on the turn of May and June. In Poland the species has one-year life cycle, i.e. one generation per year and overwinters as larvae. The main predator is the dragonfly Orthetrum cancellatum.
The objective of this study was to analyse the diversity of pine and spruce bog forests on the domes of Carpathian raised bogs located in the Upper San River Valley. In order to determine the present species composition, 59 phytosociological relevés were performed (32 within spruce forests, and 27 in pine forests). For all relevés, the Shannon-Wiener index, evenness index and mean Ellenberg indicator values were calculated. Detrended correspondence analysis was conducted in order to determine the degree of similarity between distinct units of vegetation and to identify the main environmental gradients that have an impact on species composition. The results revealed considerable similarities between the ground vegetation of both spruce and pine forests growing on peat substrate. Within pine forests there was a greater proportion of certain plant species characteristic of raised bogs, and plants typical of bog coniferous forests. The ground flora of spruce forests was more diverse. Although spruce forests predominantly contained species typical of raised bogs, there was also a group in which Molinia caerulea predominated. Ellenberg indicator values typical of pine forests lay within ranges that were characteristic of spruce forests, but pine forests occupy more humid, more acidic and poorer habitats than most patches of spruce forests. Both spruce and pine bog forests were developed as a result of the colonization of open bogs, but the time-scale and rate of intensity were different. Palaeobotanical and historical data indicate that the Scots pine first reappeared on the domes of raised bogs in the first half of the 20th century. The concept that the spruce forests are older than those of pine is supported by their greater habitat diversity. Conversely, the younger age of pine forests is confirmed by their low habitat diversity, and greater proportion of photophilous raised-bog species.
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The mycology of peatlands, with their specific plant communities and numerous rare plant species, has been underexplored and is poorly recognized. The main objectives of this study were to identify the species richness and diversity of macromycetes in raised and transitional bogs of Pomerania and to establish correlations between macroscopic fungi and peatland communities occurring in the area in view of environmental conditions. Investigations spanning a period of ten years were conducted at 134 sites (71 raised and 63 transitional bogs) in eight non-forest peatland communities (Caricetum lasiocarpae, Caricetum limosae, Caricetum rostratae, Eriophoro angustifolii-Sphagnetum recurvi, Rhynchosporetum albae, Erico-Sphagnetum medii, Sphagnetum magellanici, and the Eriophorum vaginatum-Sphagnum fallax community) and two forest communities (Vaccinio uliginosi-Pinetum and Vaccinio uliginosi-Betuletum pubescentis) in which 108 permanent observation plots were established for detailed examinations. A total of 191 macromycete species were recorded in the peatlands. The smallest number of species was recorded in Rhynchosporetum albae (12 species) and Caricetum rostratae (15 species). Phytocoenoses richest in fungi were Vaccinio uliginosi-Pinetum (102 species) and Vaccinio uliginosi-Betuletum pubescentis (121 species). The number of macromycete species recorded in individual peatland communities depends on the community type and is not conditioned by the number of observations and the number and the total area of permanent plots. Five mycosociologico-ecological groups of macroscopic fungi were distinguished based on numerical analyses. Four groups comprise species of fungi associated with a specific phytocoenosis or a group of phytocoenoses. One group consists of fungi with a broader ecological scale. The majority of environmental variables representing the substrate’s chemical properties, humidity and pH show a statistically significant influence on the diversity of macroscopic fungi species in the peatland communities. Cartogram maps of the distribution of 21 species of peatland fungi are included and geographico-ecological features of the species are briefly described.
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