Primary Succession of Springtails (Collembola) in a Norwegian Glacier Foreland

The Collembola succession was studied in the Hardangerjokulen glacier foreland in south-central Norway Twenty sampling plots 30 to 230 years of age were distributed along a chronosequence where a glacier snout had been receding since 1750 Also, five plots 10,000 years of age were sampled All soil samples were taken in Salix herbacea vegetation, in order to standardize the microhabitat The youngest zone (30-50 years) contained 14 springtail species, mainly large, surface active generalists Additional pitfall catches here revealed considerable surface activity of several species, also on vegetation-free areas Even a three-year-young moraine contained at least three springtail species Most pioneers also occurred in older soils The cumulative number of species increased rapidly up to about 70 years, at which age 72% of all species had been recorded Only five species in low numbers were confined to 10 000-year-old soil A high density of Folsomia quadrioculata and F brevicauda was noted at 50-70 years of age, and of Tetracanthella brachyura at about 100 years Compared to oribatid mites a higher number of springtail species colonized pristine ground While the two pioneer oribatids were parthenogenetic, the dominant springtail pioneers were bisexual Springtails are among the earliest colonizers along receding glaciers