Secondary succession in alvar grasslands – do changes in vascular plant and cryptogam communities correspond?

Abstract

Although bryophytes and lichens are frequently vital components of aboveground communities, their interrelationships with vascular plant communities are poorly known. We addressed small-scale covariation of vascular plant and cryptogam (bryophytes and lichens) communities during secondary succession from abandoned gravel pit towards thin soil calcareous (alvar) grassland communities. The cover, richness and diversity of vascular plants, bryophytes and lichens were studied. Whereas vascular plants showed the fastest successional dynamics in terms of richness, bryophytes showed a fast successional dynamic in terms of cover and diversity; the establishment of lichens was the slowest. THe cover, richness and diversity of different life forms changed concurrently. There were significant associations among the species composition of all life forms considered. The strongest relationship was found between lichens and vascular plants in mature stages. We conclude that alvar grasslands are certainly an example of a community in which the association between the vascular plant and the cryptogam communities may influence the overall vegetation succession, and the strength of this association increases during secondary succession.