Rewetting does not return drained fen peatlands to their old selves

Peatlands, in particular groundwater-fed fens of the temperate zone, have
been drained for agriculture, forestry and peat extraction for a long time
and on a large scale. Drainage turns peatlands from a carbon and
nutrient sink into a respective source, diminishes water regulation
capacity at the landscape scale, causes continuous surface height loss and
destroys their typical biodiversity. Over the last decades, drained
peatlands have been rewetted for biodiversity restoration and, as it
strongly decreases greenhouse gas emissions, also for climate protection.
With the dataset published here, we quantified restoration success by
comparing 320 rewetted fen peatland sites to 243 near-natural peatland
sites of similar origin across temperate Europe with regards to
biodiversity (vegetation), ecosystem functioning (hydrology, geochemistry)
and land cover characteristics based on remote sensing. Vegetation data
comes as species-specific cover values. Hydrology data covers on average
2.3 years and minimally one full year and comes as median, minimum, and
maximum water table depth. Geochemistry consists of pH and electrical
conductivity of the pore water (0-60 cm), bulk density and organic matter
content of the top soil layer (0-30 cm), all sampled in summer for all
sites included here alongside the vegetation data sampling. Land cover
characteristics contain 208 spectral-temporal metrics for a full annual
time series of Copernicus Sentinel-2 A/B data for 2018.