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The relationship between the small‐scale distribution pattern of bryophyte biomass on restored milled peatlands and substrate properties (e.g. moisture, pH, nutrients, and their ratios) was studied. Substrate properties may determine the species composition of bryophyte communities that have developed in such areas. Two experimental sites were established in northern Estonia where the moss‐layer‐transfer technique had been used for the revegetation of abandoned peatfields for almost a decade before sampling. Diaspores of Sphagnum species common on bogs were distributed in these sites. After 7 years one site was mainly dominated by Sphagnum whereas true mosses (Polytrichum strictum, Aulacomnium palustre, and Pleurozium schreberi) were abundant in the other site. Three moss groups were distinguished: Sphagnum, P. strictum, and other mosses based on cluster analysis. The biomass of Sphagnum was related to peat moisture and potassium content. For P. strictum the N/K ratio was important, and the production of A. palustre grew with the increase in the N/P ratio of peat. It was concluded that peat properties played an important role in the formation and development of bryophyte communities on revegetated peatfields on a small scale (<0.1 ha).

The number and the area of former milled peatlands under restoration have increased rapidly in the Northern Hemisphere in recent decades with the primary aim of promoting peat accumulation. However, the application of similar restoration techniques across different sites does not always lead to desired results, and some site-specific modifications may be needed. This study aimed to evaluate the response of aboveground plant biomass on three experimental sites in northern Estonia to different restoration techniques in degraded peatlands. The sites were restored using the moss layer transfer technique, which was modified with different plant spreading rates and species composition of spread material, fertilization, and creating variations in microtopography. The strongest effect of manipulations was found for bryophyte biomass responses to treatments. The creation of a microtopographic relief during the site preparation phase favored the development of Sphagnum biomass in depressions rather than in positive microforms. The species composition of the spreading material had some effect on bryophyte biomass: Sphagnum biomass was higher where hummock species had been spread. We did not find any statistical difference in the ratio of Sphagnum reintroduction tested ranging from 1:10 to 1:15.

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Rewetting is the most common restoration approach for milled peatlands in Europe, with the aim of creating suitable conditions for the development of peatland specific plant cover and carbon accumulation. Therefore, it is important to determine if time since rewetting is pivotal for milled peatlands to become functionally and structurally similar to their undisturbed counterparts. We investigate the temporal succession in rewetted peatlands in Estonia by a chronosequence of 4, 15, and 35 years before the measurements. Plant functional type (PFT) cover and biomass, bryophyte production and CO2 fluxes were measured on two milled peatlands, as well as undisturbed bogs adjacent to milled peatlands. Differences in vegetation composition and CO2 fluxes between the sites were greater for rewetted than undisturbed sites. The most recently rewetted site was mainly covered in bare peat and Eriophorum vaginatum and was a CO2 source. On the rewetted site of 15 years, Sphagnum was present in addition to ombrotrophic sedges, and in the rewetted site of 35 years, lawn-hollow microtopography is starting to develop with various PFTs. Both of these sites were CO2 sinks. Lawn Sphagnum was abundant on the two older rewetted sites, and was connected with CO2 sink functioning in the rewetted sites. Still, hummock Sphagnum species, which were present in undisturbed bogs, were absent from all of the rewetted sites. With time, CO2 fluxes, microtopography and vegetation develop after rewetting in the direction of undisturbed bogs, while vegetation composition still differs from the reference sites even 35 years after rewetting.

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