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A crucial question in ecological restoration is whether target species that are missing from aboveground vegetation are represented in the seed bank. We evaluated the role of persistent seed banks in the restoration of species richness, and the relative value of managed and unmanaged grasslands, by studying closely located and floristically similar mown and abandoned stands of fen and dry-mesophilous meadows. We found that a higher proportion of the target species detected in aboveground vegetation possessed persistent seed banks in fen meadows than in dry-mesophilous ones (44 and 29%, respectively). The proportion of target species found exclusively in the seed bank was much lower (11% for both meadow types). Conversely, common rushes (Juncus conglomeratus and J. effusus), mostly missing from the vegetation, dominated the seed banks in all fen meadow plots (50-94% of total seed densities) and were also detected in seed banks of dry-mesophilous meadows. We found that resumed mowing on previously abandoned meadows has promoted species richness and the flowering success of several species in comparison with unmanaged ones in both meadow types. Vegetation type had a stronger influence on seed bank richness and density than management status and we detected much higher seed bank densities in fen meadows (64,000-94,000 seeds/m 2 ) than in dry-mesophilous ones (4,400-6,300 seeds/m 2 ). Therefore, restoration of former richness could not be based exclusively on the local seed banks in the studied meadow types. Further management, such as hay transfer or seeding of target species, is required to increase species richness.

Abstract. Secondary succession and seed bank formation was studied in a formerly grazed, abandoned, eastern Hungarian sandy steppe‐meadow (Pulsatillo‐Festucetum). The vegetation was sampled at different elevations of a sand dune which became partly invaded by the tree Robinia pseudo‐acacia ca. 10 yr ago. Pre‐abandonment vegetation records were used as historic references. Though composition of the non‐invaded grassland only changed moderately, dominance of tall grasses (Elymus hispidus, Poa angustifolia) increased significantly at the cost of annuals and low stature perennials. In the stand invaded by Robinia most grassland species were lost and replaced by nitrophytes. Vertical position influenced species abundance, but affected the composition only moderately. Fine‐scale zonation of the vegetation also changed with time. Species richness of the above‐ground vegetation and the seed density of soil samples at the lower elevation were slightly greater than at the higher sites. Seed banks of sensitive grassland specialists (e.g. Pulsatilla pratensis subsp. hungarica) disappeared during grass encroachment. Following extinction from above‐ground vegetation, restoration must rely on dispersal from adjacent areas. In contrast, several annuals and perennials, which survived this degradation stage in the above‐ground vegetation, possessed seed banks. Many of these species became extinct from the vegetation during the Robinia invasion but left viable persistent seeds. This fact is promising for restoration of the Potentillo‐Festucetum sandy pasture. Competitive weedy species and sprouting Robinia can, however, limit seedling establishment.

Four hypotheses were tested using long-term observations of vegetation development (12 years) and present-day seed bank data in a sandy grassland area overgrazed by domestic geese: i) Gap regeneration is crucial in maintaining species richness; thus, closed vegetation of the lower sites prevents continuous establishment of short-lived species. ii) Short-lived, early successional species comprise most of the seed banks and late successional perennials have at most sparse seed banks. iii) Composition of seed banks is more similar to pioneer vegetation than to later successional stages. iv) The similarity is higher between vegetation and seed banks in the upper-positioned plots than in the closed, lower-positioned ones. Two sites, located in the upper part of dune slopes, and another two, positioned on the lower part, were studied. In each site five 2×2 m permanent plots were surveyed between 1991 and 2002. Percentage cover was estimated three times a year. In the last study year, soil seed banks were sampled. Two vertical segments (0-5, 5-10 cm) were separately analyzed. The seedling emergence method was applied on concentrated samples. We found that the vegetation developed from open, annual dominated weedy assemblages to grasslands dominated by perennial graminoids. In the lowerpositioned sites perennial clonal grasses (Cynodon dactylon, Poa angustifolia and P. pratensis) formed more closed vegetation, which was accompanied by lower species richness compared to the upper-positioned sites. Seed density varied between 10,300 and 40,900 seeds/m 2 . Significantly higher seed densities were found in upper sites than in the lower ones. Annuals and short-lived perennial dicots comprised most of the seed bank. The dominant perennial graminoids also built up dense seed banks.We found a low to medium similarity between vegetation and the seed bank; similarity was the highest with the vegetation of the 1994-1998 period. In the upper sites the similarity between seed bank and the vegetation of the last studied years was also high. The vertical position had a significant effect on regeneration after overgrazing. The large cover of grasses in lower sites decreased species richness and it also decreased the seed density preventing the seed bank formation of annuals and short-lived perennials. Here, further management practices are needed to increase the species richness.