The dynamics of populations of short-lived organisms are very patchy, both in space and time. The production of dormant propagules, however, results in an effective increase in generation time. We hypothesize that prolonged dormancy, together with variable regeneration niches, result in integration of temporal variability in community structure. In addition, in aquatic habitats, mechanisms such as sediment focussing can contribute to the integration of spatial variability. We tested the hypothesis that dormant propagule banks integrate spatial and temporal variation in active zooplankton communities. This was done by comparing cladoceran species richness and the community structure of hatchling assemblages retrieved from propagule bank samples collected on a single occasion with assemblages encountered in active community samples covering spatial variation ( littoral and pelagic zone), diel ( day and night), intra-year ( May October) and inter-year variation ( 1996 - 2000). The egg bank community structure differed significantly from the active community structure, but the dissimilarity decreased as spatial and temporal variation was better covered by the active community samples. Furthermore, the identification of all fully grown hatchlings (n = 214) yielded an equally high number of species (n = 22) to that occurring in all active community samples together ( a total of 1,730 individuals were analysed). We conclude that the analysis of dormant propagules may form a cost-efficient alternative tool to the analysis of active community samples for an integrated assessment of cladoceran communities.
- species richness dormant propagule banks spatial distribution temporal variation Cladocera resting egg banks fresh-water microsatellite analysis crustacean zooplankton horizontal migration species richness genetic changes daphnia-magna environment population Environmental Sciences & Ecology