Influence of human activity on diversity of peatland phytocenosis in Miękinia near Wrocław

The subject of investigations was the fragment of low peatland complex located close to Miękinia, about 30 km from Wrocław. Within the range of the examined area of peat bog complex there can be distinguished three parts differing in their utilization and composition of species, namely: 1/ the area degraded by the attempt to afforest it with alder trees Alnus glutinosa (L.) Gaertner, 2/ occasionally used bog hay meadow and 3/ typical peat forming phytocenosis. Total number of determined species, belonging to 11 phytosociological classes, ranged 77, out of which more than a half constitute representatives of Molinio-Arrhenatheretea class. As far as a non-afforested area was concerned, there were determined 5 phytocenosis, including 4 classified as peat forming ones and one typical for post-bog meadows (Alopecuretum pratensis). The afforested area featured herbaceous plant composition which indicated that the area with Alopecuretum pratensis phytocenosis had been degraded. Analysis of environmental requirements, done with the use of ecological numbers, proved that prevailing number of species characterize similar requirements. It was mainly afforested part to feature taxons of broader ecological scale, e.g. Polygonum bistora L., Carex hirta L. and Plantago lanceolata L. The afforested area was purchased by a private person, therefore it can be assumed that the reason for such a way of peatlands utilization was obtaining EU subsidies at minimum work effort. A higher financial profit, however, would have been made by the owner if he had maintained a bog area as an extensive meadow.