The regeneration capabilities of bryophytes for rich fen restoration

Abstract

Biodiversity in wetland habitats is strongly affected by drainage. In Sweden, rich fens (alkaline fens) have been particularly affected by drainage campaigns for forestry and conversion to agricultural land. Fragmentation of the landscape, invasion of tall vascular plants as well as Polytrichum and Sphagnum mosses and substrate degradation all lead to reduced plant diversity. We evaluated the recolonization potential of four characteristic rich fen bryophyte species that use to decrease rapidly after drainage ( Scorpidium scorpioides, Scorpidium cossonii, Pseudocalliergon trifarium and Campylium stellatum) by performing transplantation studies with gametophyte fragments in recently hydrologically restored rich fens. In greenhouse and field experiments 1 cm fragments of all four species had a high survival rate and established well, especially after surface liming of the peat. A protective cover increased the colonization success and the growth potential of the added fragments. Even small alterations of the water level (5 cm) resulted in differences in biomass growth of the fragments of S. cossonii and C. stellatum. Our results show that it is possible to reintroduce bryophyte species lost after drainage using gametophyte fragments as propagules, and that these techniques seem feasible for a number of characteristic rich fen bryophytes. These findings will be of importance when methods for practical restoration of rich fens are developed.