Soil seed bank and management regimes of semi-natural mountain meadow communities

The soil seed bank of four mountain meadow communities subjected to different degrees of agricultural management intensities was studied in the Fragen area of the Central Spanish Pyrenees. The grass-producing communities originating from former cereal crops have remained rich in floristic terms to the present day. The effects of different agricultural techniques on the seed population were analysed via soil samples, from which seedlings were identified and counted. Buried seed numbers fluctuated between 6029 and 54,517 seeds m−2 depending on the type of agricultural management. The intensively farmed, old meadows had less seed and fewer species than the extensively managed, more recent meadows. Cutting and slurry application seemed the most influential factors in the reduction of seed reserves. Taxa such as Potentilla sp., Veronica sp., and Plantago sp., were more abundant in extensive plots, while Urtica dioica, Juncus inflexus and Lamium purpureum were associated with more intensive agricultural managements. Management intensification significantly favoured plant species of nutrient rich conditions, and decreased numbers of pioneer, and nutrient poor conditions species.