Trajectories of plant recovery in block-cut peatlands 35 years after peat extraction

Abstract

The initial question of any ecological restoration project should be whether the degraded ecosystem may recover spontaneously in a reasonable time period or active intervention is needed. We examined the successional trajectories of vegetation within peatlands exploited by the traditional blockcut technique in Eastern Canada, with the final purpose of identifying sites which need human intervention to ensure the return of a typical Sphagnum-dominated bog community that accumulates C. Ordinations showed that the development of vegetation was different between three block-cut peatland regions. Peatlands of one of the regions were initially colonized by tall, dense ericaceous shrubs. There, communities tended to become increasingly dominated by trees and understories were closing over time, therefore not being on a trajectory toward the recovery of a Sphagnum-dominated system that accumulates peat in the future. Intervention is therefore recommended, for example by blocking still active drainage ditches. In the peatlands of the other two regions, Sphagnum had a high initial cover and remained dominant ten years later. However, species typically found in hummocks gained relative importance vs. those associated to hollows. More time is needed to decide whether these sites could be left unmanaged as they have remained after their abandonment 35 years ago. © 2013, ALÖKI Kft., Budapest, Hungary.