Rapid plant colonization of the forelands of a vanishing glacier is strongly associated with species traits

Recently developed glacier forelands provide valuable insights into vegetation dynamics. We studied the vascular plants in the glacier forelands of the Ålmajallojekna glacier in comparison to the plants in the surrounding area. The glacier is retreating rapidly at an average rate of 0.17 km2 per year from 1898 to 2012. In the newly emerged glacier forelands, we found that 32 percent of the 381 plant taxa occurred in the surrounding region. Sixty-eight plant species were present on the youngest terrain (0–31 y), an additional thirteen species occurred on terrain aged 32–53 years, and an additional fortytwo species were detected on terrain aged 54–114 years. Of the surrounding species pool, plant species that had successfully established in recently deglaciated terrains were characterized by high regional abundance and low seed weight, and they were more likely to be members of the plant families Saxifragaceae, Salicaceae, and Asteraceae. Woody plant species with a preference for welldrained soils were more likely to be present in the youngest terrain. Our results show that the vegetation of glacier forelands is developing rapidly depending on the plant species in the surrounding area and the species’ life-history traits.