Application of oil-shale ash and straw mulch promotes the revegetation of extracted peatlands

Our results showed that application of oil-shale ash and straw mulch, as well mulch alone promote clearly revegetation in studied extracted peatlands (mean plant cover 57% and 40% on fifth year, correspondingly), but at the same time quadrats with oil-shale ash alone were sparsely vegetated (4%) and similar to plots without any treatment (2%). Oil-shale ash alone did not speed up the establishment of plant species, but oil-shale ash combined with straw mulch facilitated the establishment of some species typical of natural mires. Closeness to the peatland edge increased the number of species and their cover because of the location and proximity to naturally vegetated areas. Consequently, oil-shale ash combined with straw mulch or straw mulch alone facilitated plant growth on extracted peatlands, while the effect of oil-shale ash alone was unimportant.