Wet meadows of the alliance Molinion and their environmental gradients in Slovenia

The main objective of this study was to examine the relationships between wet meadow plant communities of Molinon alliance and their environmental conditions in Slovenia. The ecology of these communities was analysed in detail. The study provides the data on the vegetation and environmental parameters, the significance of parameters for the plant species composition, most important environmental gradients and differences between plant communities. In all plots the vegetation was recorded and soil parameters were analysed (pH, plant-available P and K, N-t, organic C, C/N ratio, exchangeable Ca2+, Mg2+, K+, Na+, H+, electrical conductivity, base saturation). Other conditions were also considered (e.g., mean annual temperature and precipitation, humidity index, mean Ellenberg moisture and nutrient value) to test possible correlations as well. Vegetation was classified by means of multivariate cluster analysis, while vegetation-site relationships were examined with direct gradient analysis (CCA). Six associations from the Molinon alliance (Selino-Molinietum, Plantagini altissimae-Molinietum, Carici davallianae-Molinietum, Gentiano-Molinietum litoralis, Junco conglomerati-Betonicetum and Sanguisorbo-Festucetum commutatae) were identified and analysed. Soil reaction was identified as most significant environmental parameter explaining the variation of the studied vegetation. There are several statistically significant differences in site conditions between the communities (pH, moisture, nutrient status, Ca2+). The studied associations represent clearly defined ecological units.