Data: Small-scale fen restoration brings back key species and ecosystem functions

Overview This repository contains data supporting the publication: Johannes Merz, Franziska Willems, Lena Lerbs & Anna Bucharova. 2026. Small-scale fen restoration brings back key species and ecosystem functions. Journal of Applied Ecology (in press). Study System Vegetation composition and peat depth were recorded in 26 temperate fen sites in Germany. We compared sites with varying restoration histories (0–38 years since rewetting following forestry drainage) to degraded and near-natural reference sites. Data was recoreded at each site, along three transects, each transect consisted of five 1m² (1x1 m) plots with 1m between plots. In each plot, we identified peat depth and all vascular plants, bryophytes, liverworts and macro fungi, and recorded their cover in percent. Data Files Data_wide.csv Metadata and vegetation data in wide format. Each row = one plot/transect record. Columns include plot, site and transect ID, site status (near-natural/restored/unrestored), and cover values (%) for each recorded species. For restored sites also the year of restoration. Ther are some further data on habitat characteristics that were not used in the analysis of the refered publication. Data_transect_level.csv Transect-level aggregated data used in GAM analyses of vegetation and peat recovery between near-natural, restored and unrestored sites as well as over time since restoration. Fen specialist species in the vegetation records included in the dataset above ("Data_wide.csv") were determined based on the characteristic species combinations defined in the updated 2025 EUNIS-ESy framework (Available via Zenodo: https://doi.org/10.5281/zenodo.16895007). The EUNIS-ESy data was originally published in: Chytrý, Milan, Lubomír Tichý, Stephan M. Hennekens, et al. 2020. ‘EUNIS Habitat Classification: Expert System, Characteristic Species Combinations and Distribution Maps of European Habitats’. Applied Vegetation Science 23 (4): 648–75. https://doi.org/10.1111/avsc.12519. Variables: - `transect_unique`: Unique transect identifier - `site.ID`: Site identifier - `site.status`: Restoration status (near-natural / restored / unrestored) - `site_type_detailed`: Detailed status, distinguishing restored_young vs. restored_old (near-natural / unrestored / restored_young / restored_old) - `year`: Years since restoration [NOTE: clarify coding for near-natural/unrestored] - `mean_peat`: Mean peat depth per transect (cm), averaged across plots - `number_of_species`: Total number of vascular plant species per transect - `number_of_specialists`: Number of fen specialist species per transect, based on EUNIS fen specialist classification - `Specialist_cover`: Average % cover of fen specialist species per transect (summed per plot, averaged across 5 plots per transect) - `Specialist_cover_proportion`: Specialist_cover expressed as a proportion (0–1) rather than percentage