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The occurrence of Atriplex littoralis L. in Poland

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The Atriplex littoralis L. is a rare and endangered species in Poland and many other countries in Europe. In Poland it is mainly found on the west coast and also rarely in central parts. It has been seen in Puck Bay and the Gulf of Gdańsk as well as in Hel Peninsula. The grassleaf orache is a halophyte, terophyte and a sunlight-loving plant. Data shows that apart from on the coast, this species may also appear in inland areas, for example on ruderal habitats such as roadsides. The results of our observations confirm the presence of the species on beaches and rocky bank reinforcement, with accumulation of annual vegetation in the Hel Peninsula and Puck Bay. Five sites, where Atriplex littoralis specimens occur have been found. In each site 1 to 15 specimens where found, in total 31. Five phytosociological relevés were made within the floristically poor patches of Matricario maritimae-Atriplicetum littoralis (Christiansen 1933) R.Tx. 1950. This association represents the protected type of habitat: Annual vegetation of drift lines (1210).
The impact of burrows constructed by plateau zokors Myospalax fontanierii (Milne- -Edwards, 1867) on alpine meadow vegetation on the Qinghai-Xizang (Tibetan) plateau was investigated. Plant samples taken from quadrats directly over active zokor burrows, back-filled burrows, adjacent burrow controls, and random sites from a field, in which no burrows or mounds occurred were compared. The biomass of plants (below- and above-ground) directly over shallow active burrows was significantly lower than on control plots. This reduction in biomass was not significantly different than that between deep active burrows and control plots. There were no significant differences between above- and below-ground plant biomass on areas perpendicular to active burrows when compared to random sites. Back-filling soil in burrows could promote the growth of above-ground monocotyledonous plants. However, the burrowing activities of zokors had a negative effect on biomass of dicotyledonous plants.
The paper presents results of the studies conducted to determine causes and directions of transformations in vegetation of meadow-pasture communities in the area of the Wielki Łęg Obrzański [Great Obra Floodmeadows]. Multifaceted natural and habitat analyses were conducted on over 1800 relevés prepared in the vegetation seasons of 2005–2009 according to Braun-Blanquet. On their basis the phytosociological and floristic structure was analysed and habitat conditions were determined by phytoindication. Moreover, laboratory methods were applied in soil analyses to determine contents of basic macro- and microelements and groundwater table levels were recorded. Results referred to the documentation and archive literature made it possible to determine causes of transformations in plant communities in that area and outline probable directions in which succession was progressing. A lack of regular land use patterns is seen as the primary cause for the transformation in the flora of the Wielki Łęg Obrzański, particularly in the last 20 years. A considerable limitation of land use in certain sections of this area has led to the initiation of dominance of nitrophilic species such as Urtica dioica, Cirsium arvense, Potentilla anserina or Galium mollugo, while in the thinned sward it led to the development of grass species with very limited economic importance. Another equally important factor affecting the structure of vegetation cover is connected with air and water relations in soils, determined by the drainage system operating there for the last 200 years and by precipitation.
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The aim of this study was to characterise the flora and plant communities in the Moryńskie Hills, Poland. A total of 45 transects and 23 phytosociological relevés were established. Plant communities were identified based on the description of the test patch of the vegetation cover. The paper presents floristic analyses of vascular plants, which includes the taxonomic affiliation of species, their life forms according to Raunkiaer, and the species share in the geographical and historical groups. The results have been compiled and presented in tables and graphs, with a brief discussion. The non-forest communities occupy the largest area: xerothermic swards, meadows and pastures and to a lesser extent, scrub communities. Forests are represented by a riparian slope elm-ash wood Violo odoratae-Ulmetum minoris.
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