Monique Poulin, Line Rochefort, and Isselin-Nondedeu Francis. Peatland Ecology Research Group (PERG)
Restoration specialists are often criticized
for not establishing a proper monitoring program that
would help judging the achievement of the restoration. Here, we present a study
case where monitoring has taken place during 7 years after restoring a cut-over
bog. The aim of this presentation is 1) to assess peatland restoration success when
using the dry surface restoration approach and 2) to compare different
monitoring methods for assessing restoration success. The site is a cut-over
bog of 11.4 ha, of which 8.5 ha were restored in 1999. The restoration approach
consisted mainly in reintroducing bog-plant diaspores,
spreading a straw mulching, blocking the former drainage ditches, and applying
a low dose of phosphorus fertilizer. The vegetation was
surveyed by point interception method using a systematic grid of
approximately 6900 points (every 3 m × 5 m)
before (1999) and after restoration (2001,
2003 and 2005). In addition, permanent plots were established and surveyed
every year since 1999. The recovery of vegetation was assessed with a
reference ecosystem. Sphagnum had a
frequency of occurrence of 55% in 2005 from the point interception survey,
which is close to what was found in the reference ecosystem. The cover of the
nursing moss Polytrichum strictum were
two times more abundant in the restored site than in the reference ecosystem in
2003 but slowly decreased since 2005. The cover of the herb strata was also higher
than in natural peatlands but we expect a decrease of the main herb species, Eriophorum vaginatum (cotton-grass)
with time. Overall, the dry surface restoration approach appears to be
efficient for successfully re-establishing plant diversity on cut-over bogs. Discrepancies
between the two survey techniques will be discussed for vegetation strata and
particular species.
