Selection towards lighter seeds in Danish grasslands over an eight-year period

Abstract

AbstractTime-series analysis of cover data from 236 Danish grassland sites demonstrated community selection on seed mass. Across four grassland habitat types and during an eight-year period there was a benign but significant community selection towards lighter seeds. The relatively benign observed change in seed mass may partly be due to a relatively conservative analysis, where the continuous plant trait variables are used for grouping plant species into functional types, which are then treated as dependent variables. This method was chosen in order to account for the sampling process of the vegetation data and is in contrast to most other analyses of trait selection, where the community weighted mean of the traits is used as the dependent variable. Generally, little is known on the underlying causes of possible plant trait community selection in semi-natural grasslands that are not subjected to successional processes.