The viable propagule banks of a tempo- rary stream were studied from sections with different agricultural history. Hatching of zooplankton (cope- pods, rotifers and cladocerans) was recorded in the laboratory under controlled temperature and light conditions from an agriculturally modified area with average hydroperiods of about a week per year and two semi-natural reference areas with average hyd- roperiods of more than 3 weeks per year. We found significant differences in both taxon richness and abundance of zooplankton hatching between areas, which were lower in the agriculturally modified section, compared to the reference sections. Another factor likely to have influenced hatching in our experiment was conductivity, which differed between the two reference sections and might have affected hatching at high conductivities. For restora- tion purposes, hydrological reconnection of stream segments is important to facilitate dispersal from the high diversity upstream segments to the depleted sites downstream

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