Management history affects grassland seed bank build-up

摘要

Disturbance in the form of different management regimes affects established vegetation, but how the same management affects the corresponding seed banks is poorly understood. We used the seedling emergence method to investigate how present and previous management intensity impacts the dynamics of established vegetation and corresponding seed bank in six semi-natural grasslands (three pastures and three road verges) in W Norway. The increased management intensity reduced seed bank species richness but increased seedling density and the fraction of species with a persistent seed bank. Higher intensity also increased the components' floristic similarity, probably through formation of gaps where seeds may germinate. Moreover, the seed bank responded in parallel with the established vegetation to underlying environmental variables as well as to management intensity. Management intensity hence impacted directly on many aspects of seed bank-established vegetation relationships, and controlled established vegetation partly through seed bank dynamics involving both temporal and spatial dispersal.