Spring fen Scheuchzerio-Caricetea nigrae in the Polish Western Carpathians – vegetation diversity in relation to soil and feeding waters

anglais. The species composition of vegetation associated with the Carpathian fens primarily depends on the type of water present and the hydrological feeding of the soils that occur there. These, in turn, shape the fertility of the fens. Those with typically formed Carici-Agrostietum caninae and Valeriano-Caricetum flavae fundamentally differ in the properties of their soils and feeding waters. These include differences in mineral content, pH, CaCO3 levels, degree of peat decomposition, electrical conductivity and oxygenation of the waters that feed the fens. Carici-Agrostietum caninae is a homogenous plant association adapted to extreme habitat conditions. It is characterized by a very narrow range of essential soil and feeding water parameters. Valeriano-Caricetum flavae is a highly diverse association. Considerable diversity both in terms of plant species and vegetation structure reflects very wide ranges in the properties of soil and feeding water. Vegetation patches of transitory character were also identified. These contained plant species characteristic of both associations. The character of the vegetation depends mainly on fen soil pH and the degree of mineralization of the feeding waters. It is only these parameters that allow intermediate patches to be clearly distinguished. The degree of peat decomposition, mineral content and water oxygenation all differ for Carici-Agrostietum caninae and Valeriano-Caricetum flavae, whereas the values for intermediate patches display a range of parameters typical of both investigated associations. Consequently, vegetation present in these patches reflects to a greater or lesser extent one of the two analyzed plant associations.

anglais. Carici-Agrostietum caninae, Valeriano-Caricetum flavae, fens, soil and water properties, Western Carpathians, Poland

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