Functional diversity analysis helps to identify filters affecting community assembly after fen restoration by top-soil removal and hay transfer
This study is summarised as evidence for the following.
Remove upper layer of peat/soil (without planting)Action Link
Introduce seeds of peatland herbsAction Link
Remove upper layer of peat/soil (without planting)
A replicated, controlled study in 2008–2011 in a degraded fen in Poland (Hedberg et al. 2014) reported that plots stripped of topsoil developed a different plant community to unstripped and natural plots, but found that all plots contained a similar number of vascular plant species. After three years, the overall composition of the plant community differed between stripped, unstripped and natural plots. In particular, stripped plots had greater cover of jointleaf rush Juncus articulatus, cattail Typha latifolia and common duckweed Lemna minor than both unstripped and natural plots (data reported as a graphical analysis; differences not tested for statistical significance). However, the number of vascular plant species did not significantly differ between treatments (data not reported). In December 2008, 60 cm depth of topsoil was stripped from two 0.5 ha plots in the drained, degraded fen. Soil was not stripped from five adjacent plots. None of these plots were sown with hay. Ten plots in two natural fens were also monitored. In summer 2011, cover of every vascular plant species was estimated in each plot.
Introduce seeds of peatland herbs
A replicated, controlled, before-and-after study in 2008–2011 in a degraded fen in Poland (Hedberg et al. 2014) found that adding seed-rich hay to plots did not affect vascular plant community composition or species richness. Ten drained plots were initially dominated by dryland plants. The overall composition of the plant community did not change over two years, whether hay was added or not. Two other, wetter plots were initially dominated by fen-characteristic herbs. In these plots, rushes and reeds became more abundant over two years, whether hay was added or not (all community data reported as a graphical analysis; results not tested for statistical significance). After two years, the number of vascular plant species was not significantly different in plots with or without added hay (data not reported). In autumn 2009, twelve plots were established in a drained, degraded fen. Ten plots remained fully drained. Hay from a nearby natural fen was spread onto five of these plots. Two plots were wetter, having been been stripped of 60 cm of topsoil 6–8 months before the initial vegetation sampling. Hay was spread onto half of each of these plots. In summer 2009 (before hay addition), 2010 and 2011, cover of every vascular plant species was estimated in each plot (details not clear).