Participation of grassland species in various successional series in a temperate European region and implications for habitat management

Abstract

Restoration strategies of semi-natural grasslands at various disturbed sites require an understanding of the resilience of these habitats and knowledge of their specific successional dynamics. Here, we assess (i) to what extent and under what circumstances grassland species can spontaneously establish and survive in various successional series, and (ii) whether some successional stages may provide surrogate habitats for typical grassland species. Besides grassland species, we evaluated the participation of other species groups, namely woodland, synanthropic and open wetland species, to demonstrate general successional trends. We studied 12 different successional series ca 60 years long in the Czech Republic, central Europe, and evaluated changes in species numbers and cover of species groups. Our results showed grassland species participated not only temporarily but also continuously during the first six decades of succession, as we had expected. Their decline in the late successional stages was only slightly visible despite the formation of woodland in most successional series. In some cases, the woodland was not completely closed and still allowed some grassland species to survive in the understorey. However, we found clear negative correlations between the participation of grassland and woodland species in the late successional stages. Woodland species generally increased, while synanthropic species clearly decreased during succession. Open wetland species slightly decreased, probably due to increasing site terrestrialisation in several successional series. The number and cover of dry grassland species decreased with increasing altitude, while those of mesic grassland species increased, indicating a decisive role of climate for their participation in succession. Successional trends discussed here represent general patterns but cannot be automatically applied in restoration without considering the specificity of each successional series. The establishment of grasslands in most successional series can be prevailingly maintained by management to reduce the establishment and expansion of woody species, otherwise grasslands only rarely persist in habitats under extreme site conditions or certain natural disturbances.