Long-term effects of drainage and initial effects of hydrological restoration on rich fen vegetation

  • Published source details Mälson K., Backéus I. & Rydin H. (2008) Long-term effects of drainage and initial effects of hydrological restoration on rich fen vegetation. Applied Vegetation Science, 11, 99-106.


This study is summarised as evidence for the following.

Action Category

Rewet peatland (raise water table)

Action Link
Peatland Conservation
  1. Rewet peatland (raise water table)

    A before-and-after study in 1995–2006 in a degraded rich fen in Sweden (Mälson et al. 2008) reported that following rewetting, plant species richness, Sphagnum moss cover and tree cover increased, but cover of shrubs and purple moor grass Molinia caerulea decreased. These results were not tested for statistical significance. Plots contained 13–15 plant species before rewetting but 18–27 species four years after. In the plot where it occurred, cover of spiky bog moss Sphagnum squarrosum was 1% before rewetting but 13% after. Tree cover was 9–18% before rewetting but 13–20% after. In contrast, cover of purple moor grass was 58–74% before rewetting but only 32–62% after, and cover of shrubs 11–26% before rewetting but only 1–5% after. There was no clear change in cover of sedges Carex spp. (before: 0–1%; after: 0–2%) or two fen-characteristic moss species (0% before and after). In December 2002, the water table of a drained fen was raised approximately 17 cm by blocking a drainage ditch. Cover of every plant species was estimated in summer before (1995, 1997 or 2002) and after (2006) rewetting, in nine 1 m2 quadrats in each of two plots.

    (Summarised by: Nigel Taylor)

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