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Peatland degradation through drainage and peat extraction have detrimental environmental and societal consequences. Rewetting is an option to restore lost ecosystem functions, such as carbon storage, biodiversity and nutrient sequestration. Peat mosses (Sphagnum) are the most important peat-forming species in bogs. Most Sphagnum species occur in nutrient-poor habitats; however, high growth rates have been reported in artificial nutrient-rich conditions with optimal water supply. Here, we demonstrate the differences in nutrient dynamics of 12 Sphagnum species during their establishment in a 1-year field experiment at a Sphagnum paludiculture area in Germany. The 12 species are categorized into three groups (slower-, medium- and fast-growing). Establishment of peat mosses is facilitated by constant supply of nutrient-rich, low pH, and low alkalinity surface water. Our study shows that slower-growing species (S. papillosum, S. magellancium, S. fuscum, S. rubellum, S. austinii; often forming hummocks) displayed signs of nutrient imbalance. These species accumulated higher amounts of N, P, K and Ca in their capitula, and had an elevated stem N:K quotient (>3). Additionally, this group sequestered less C and K per m2 than the fast and medium-growing species (S. denticulatum, S. fallax, S. riparium, S. fimbriatum, S. squarrosum, S. palustre, S. centrale). Lower lawn thickness may have amplified negative effects of flooding in the slower-growing species. We conclude that nutrient dynamics and carbon/nutrient sequestration rates are species-specific. For bog restoration, generating ecosystem services or choosing suitable donor material for Sphagnum paludiculture, it is crucial to consider their compatibility with prevailing environmental conditions.

De ecologische kwaliteit van het Markermeer is sinds de aanleg van de Houtribdijk sterk achteruitgegaan. Die Houtribdijk weer weghalen is geen optie, al was het maar omwille van de ‘ecosysteemdiensten’, zoals de waterhuishouding. In 2016 is een alternatieve aanpak gekozen: uit de zachte sedimenten van het kunstmatige Markermeer is een archipel van vijf eilanden aangelegd: Marker Wadden. Het Markermeer kreeg daarmee weer geleidelijke land-waterovergangen, verschillende waterdiepten en beschutting tegen golven en sedimentophoping. Dit artikel beschrijft de eerste resultaten. Het voedselweb wordt ‘van onderaf’ hersteld door de primaire productie via algen te verbeteren, waar ook hogere planten en dieren van profiteren. Dit project illustreert hoe herstel van ecosystemen in meren kan worden bereikt met behoud van bestaande ecosysteemdiensten.