PERMACULTURE - How shrubs are reducing the positive contribution of peatlands to climate

Peatlands (bogs, turf moors) are among the most important ecosystems worldwide for the storage of atmospheric carbon and thus for containing the climate warming process. In the last 30 to 50 years the peat (Sphagnum) mosses, whose decay produces the peat (turf), have come under pressure by vascular plants, mostly small shrubs.
http://www.sciencedaily.com/releases/2012/12/121223180005.ht