Factors affecting re-vegetation dynamics of experimentally restored extracted peatland in Estonia

Abstract

Increasing human activity continues to threaten peatlands, and as the area of natural mires declines, our obligation is to restore their ecosystem functions. Several restoration strategies have been developed for restoration of extracted peatlands, including "The moss layer transfer method", which was initiated on the Tässi extracted peatland in central Estonia in May 2012. Three-year study shows that despite the fluctuating water table, rainfall events can compensate for the insufficient moisture for mosses. Total plant cover on the restoration area attained 70 %, of which ~60 % is comprised of target species-Sphagnum mosses. From restoration treatments, spreading of plant fragments had a significant positive effect on the cover of bryophyte and vascular plants. Higher water table combined with higher plant fragments spreading density and stripping of oxidised peat layer affected positively the cover of targeted Sphagnum species. The species composition in the restoration area became similar to that in the donor site in a natural bog. Based on results, it was concluded that the method approved for restoration in North America gives good results also in the restoration of extracted peatland towards re-establishment of bog vegetation under northern European conditions.

Impact of water table level on annual carbon and greenhouse gas balances of a restored peat extraction area

“…As the last step, straw mulch was applied to protect plant fragments from solar radiation and to improve moisture conditions. Further details about the restoration procedure at this study site have been given in Karofeld et al (2015).…”

“…), downy birch (Betula pubescens Ehrh. ), bog rosemary (Andromeda polifolia L.) and Scots pine (Pinus sylvestris L.), with a minor cover of accompanying herbaceous sedge and forb species such as tussock cottongrass (Eriophorum vaginatum L.) and round-leaved sundew (Drosera rotundifolia L.) (Karofeld et al, 2015).…”

How can we restore biodiversity and ecosystem services in mining and industrial sites?

“…In the papers of this issue, attention is given to passive restoration and the factors influencing spontaneous succession (e.g., Nikolic et al 2015;Tropek et al 2015;Horáčková et al 2015;Alday et al 2015), to field experiments comparing ecological restoration measures (Tarvainen and Tolvanen 2015;Karofeld et al 2015), to the comparison between reclamation and passive restoration (Řehounková et al 2016; Šebelíková et al 2015), and to the reclamation by afforestation (Metslaid et al 2015). Based on the results, passive restoration seems to be an effective approach at many post-mining and postindustrial sites (but see Kopeć et al 2015), whereas technical reclamation may have negative effects on the biodiversity, since it decreases the amount of habitats for specialized threatened species (Tropek et al 2015;Řehounková et al 2016) or maintains the pool of seeded alien species that may spread to the surrounding environment (Rydgren et al 2015).…”

“…On the other hand, technical reclamation can be justified through the economic profit as in the case of timber production of afforested sites (Metslaid et al 2015). Experimentally tested ecological restoration measures (Tarvainen and Tolvanen 2015;Karofeld et al 2015) and analyses of environmental and plant characteristics influencing the regeneration and succession Alday et al 2015;Nikolic et al 2015) provide scientific information that can be used in developing effective ecological restoration under adverse conditions. A special and, in some cases, the only possible restoration measure is the ex situ conservation of endangered species which can be later used in ecological restoration projects (Le .…”

“…Undisturbed neighboring ecosystems such as forests (Alday et al 2015;Tarvainen and Tolvanen 2015), peatlands (Karofeld et al 2015), and the tundra (Rydgren et al 2015) may be used as a reference for ecological restoration, but they may not always be a valid reference for large-scale mining or industrial sites. An alternative stable state should also be considered (Alday and Marrs 2014).…”