Abstract | The restoration of bogs has received considerable attention in recent years. Given that no truly natural bogs remain in the lowlands of Britain (Lindsay & Immirzi 1996), those who take on the management of an ombrotrophic bog system, particularly in the lowlands, are generally faced with a site requiring significant, if not substantial, ‘restoration’ management. A considerable body of experience about restoration methods for conservation purposes has accumulated over the years and its compilation in Brooks & Stoneman (1997) for the UK and, for example, Dupieux (1998) and Manneville, Vergne & Villepoux (1999) for France, complements the detailed review of restoration on commercially cut-over bogs undertaken by Wheeler & Shaw (1995). Concept of ‘restoration’ Ideally, the objective, and indeed the measure of success for such activities, might be based on complete restoration of all original features. Some components of a peat bog can, however, never be recreated (the peat archive, for example). The practical objective for peatland restoration must therefore be focused on the reinstatement of an ecological process rather than any particular end point. For the purposes of the EU Habitats Directive (EC Directive 92/43/EEC) the Commission definition of “damaged raised bog capable of natural regeneration” specifies that “there is a reasonable expectation of re-establishing vegetation with peat-forming capability within 30 years” (Romão 1996). Such wording makes it clear that, in the European Commission view, successful restoration is achieved when the potential for peat formation once again exists. In other words the resulting vegetation should be one that is widely accepted as being capable of forming peat. The timescale of 30 years can be regarded as a useful milestone that encourages judgments of success to be made within a specified period rather than leaving the question completely open-ended. The EC does not require the complete reconstruction of a peat bog, with all its structural features, within 30 years. If the EC definition is taken as the yardstick of restoration success (and it is difficult to find specific or better alternative forms of yardstick within the literature), the key is clearly the establishment of appropriate peat-forming vegetation. Given this objective, it is very important to understand the mechanisms by which such vegetation types arise spontaneously when devising, evaluating or choosing restoration techniques for a particular bog. Peat formation and restoration This paper will consider the natural processes of peat bog formation and structure, as they relate to bog restoration via the establishment of peat-forming vegetation. It sets out a conceptual framework for these various approaches, and compares the benefits of differing restoration strategies. |
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