Plant Trait Composition in Lowland Calcareous and Acidic Semi-Dry Grasslands

European semi-dry grasslands are habitats of high conservation value. Therefore, research into the mechanisms of community assembly is important for their effective management. Using data from 76 vegetation plots of calcareous and acidic semi-dry grasslands in continental Slovenia, the author analysed the composition of plant traits, focusing on less studied belowground traits. Community-weighted means were calculated for nine plant functional traits: life form, growth form, clonal growth organ (CGO) type, persistence of connection in CGO, number of clonal offspring shoots, lateral spreading distance, role of CGO, bud bank, CSR strategy. The results showed that both grassland communities were characterized by high local persistence (perennial plants with long-lived connections between ramets). Acidic grasslands had more species with rosettes, rhizomes and stress-tolerators, indicating more stressful conditions, probably due to low pH. Mesic grassland species with numerous stolons and longer lateral spread were also characteristic of acidic grasslands. Calcareous grasslands hosted more competitors, plants with leafy stems and plants with perennial main roots. This study contributes to a deeper understanding of grassland processes and provides a basis for future investigations of belowground plant traits and their function.