Conservation Evidence strives to be as useful to conservationists as possible. Please take our survey to help the team improve our resource.

Providing evidence to improve practice

Individual study: Rewetting of drained boreal spruce swamp forests results in rapid recovery of Sphagnum production

Published source details

Maanavilja L., Kangas L., Mehtätalo L. & Tuittila E.-S. (2015) Rewetting of drained boreal spruce swamp forests results in rapid recovery of Sphagnum production. Journal of Applied Ecology, 52, 1355-1363


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Rewet peatland (raise water table) Peatland Conservation

A replicated site comparison study in 2011–2012 in 36 forested fens in Finland (Maanavilja et al. 2015) found that in rewetted sites, Sphagnum moss growth was greater than in drained sites, and similar to undrained sites. After 3–16 years, Sphagnum biomass growth in rewetted sites (147 g/m2/year) was significantly greater than in sites that remained drained (76 g/m2/year) and not significantly different to never-drained sites (128 g/m2/year). The same was true for length growth (rewetted: 6; drained: 3; never-drained: 5 g/m2/year). Of the 36 forested fens studied, 18 had been rewetted in 1995–2008 by filling or blocking drainage ditches, nine remained drained (ditches open) and nine had never been drained. In May 2011, nine 13 x 13 cm plastic nets were installed on the rewetted peat in each site. In May 2012, all Sphagnum growing above each net was harvested, then dried and weighed. Stem length was measured for 20 shoots/net. This study used the same sites as (30).

(Summarised by Nigel Taylor)