Spontaneous revegetation of mined peatlands: An useful restoration tool?

The recent development of peatlandrestoration activities indicates thatmodern peat mining techniques seriouslyhamper the natural capacity of bogecosystems to regenerate after adisturbance. However, some plants have theability to colonize dry peat deposits, andseem to help stabilize the soil surface andfacilitate the establishment of other plantspecies. In this paper, we review studiesregarding the spontaneous regeneration ofombrotrophic peatlands. There are numerousexamples throughout North America andEurope showing that spontaneousrevegetation of mined peatlands by typicalbog plants, and particularly by Sphagnum species, is possible. However,this phenomenon is much more common inblock-cut peatlands than in vacuum-minedsites. The slow recovery of vacuum-minedpeatlands compared to block-cut sites isprobably related to intense drainagenecessary for the use of tractor-drawnvacuum machines. There are some cases,however, where the spontaneous revegetationof vacuum-mined sites is successful,particularly for vascular plants. Thesesites are mainly dominated by cotton-grass(Eriophorum vaginatum L.). Itseems that the microclimatic conditionscreated by cotton-grass tussocks improveestablishment conditions for other vascularand non-vascular plants. Restorationactivities should be minimal in minedpeatlands already invaded by cotton-grass,and spontaneous revegetation processescould and should be integrated intopeatland restoration programs.[PUBLICATION ABSTRACT]