Exploring the Potential of Sphagnum Paludiculture as a Substitute Habitat for Peatland-Associated Beetles: Insights from a Long-Term Study in Northwestern Germany

Abstract Sphagnum paludiculture is the cultivation of Sphagnum (peat moss) on rewetted degraded bogs to produce Sphagnum biomass as a sustainable alternative to peat in horticultural growing media. The transformation of land use resulted in changes in biodiversity. The value of Sphagnum paludiculture as a surrogate habitat for peatland species requires further investigation. Here, we report the results of ten years of biodiversity monitoring (2011–2020) at a Sphagnum paludiculture site in northwestern Germany, using ground and rove beetles (Carabidae and Staphylinidae) as indicator groups. The species richness tended to decrease over time. Abundance increased in the early years but decreased by the end of the study period. In the first year, peatland generalist species (i.e. Agonum gracile Sturm, 1824) appeared, and after two years, peatland specialists started to populate the plots (e.g. Philonthus nigrita (Gravenhorst, 1806), Agonum munsteri (Hellén, 1935)). However, peatland specialists were not the dominant element, as the beetle assemblages did not reach the composition of natural peatlands. High turnover rates with respect to species composition and dominance indicate the existence of dynamics in the community. It is evident that an equilibrium has yet to be reached; thus, the manner in which succession will continue to develop on the Sphagnum paludiculture site remains uncertain. The findings of our study indicate that Sphagnum paludiculture may serve as a surrogate habitat for peatland-associated beetles, at least for certain species, and thus represents a significant improvement in biodiversity in previous drainage-based land use.