Comparison of plant traits of sedges, shrubs and Sphagnum mosses between sites undergoing forest-to-bog restoration and near-natural open blanket bog: a pilot study

In the UK, the majority of peatlands have been damaged by drainage, agriculture, forestry plantations or erosion, compromising the ecosystem services they deliver including carbon sequestration. On the other hand, since the 1990s many projects have carried out a range of interventions to restore peatlands. In forest-to-bog restoration, tree removal and drain blocking lead to immediately visible changes. However, while some key plant species return within years, they may continue to exhibit differences in how they perform and interact with their environment. To investigate this, plant functional traits were measured and compared for Calluna vulgaris, Erica tetralix, Eriophorum angustifolium, Eriophorum vaginatum, Sphagnum capillifolium and Sphagnum papillosum collected in an open blanket bog, a forestry plantation and two forest-to-bog restoration sites in northern Scotland. Significantly lower specific leaf area and chlorophyll content, and higher leaf dry matter content, were found in the open bog site compared with plantation and forest-to-bog sites. This could be related to nutrient enrichment derived from brash and needle decomposition in the latter sites, suggesting a lasting effect of coniferous plantations even after decades of restoration management. Altered plant functional traits may have feedbacks on ecosystem processes such as litter decomposition and peat formation.