Meta‐analysis reveals that enhanced practices accelerate vegetation recovery during peatland restoration

Abstract

The provision of critical ecosystem services like carbon sequestration by peatlands has been degraded around the globe. Peatland restoration represents an opportunity to tackle the twin global emergencies of climate breakdown and biodiversity decline. Nonetheless, restoration success relies on a sound understanding of recovery trajectories associated with different restoration techniques. Focusing on temperate/boreal Sphagnum‐dominated peatlands, we used a quantitative meta‐analysis of 28 studies representing 275 sites in 11 countries to test for effects of peatland status (intact, restored, and degraded), varying restoration interventions and time since restoration on vegetation as a key indicator of peatland condition and functioning. Enhanced restoration (such as active revegetation) resulted in recovery to predisturbance levels within 30–35 years for Sphagnum mosses, and 20–25 years for many other peatland specialist species, and was the only restoration approach where positive outcomes were seen across all vegetation response variables. The use of standard restoration techniques, such as rewetting, was projected to result in cover of Sphagnum mosses and peatland specialist plants reaching that of intact sites within 45–55 years post‐restoration. Passive restoration (cessation of the degrading activity with no active restoration) generally elicited limited recovery of keystone peatland vegetation (Sphagnum spp.) even after multiple decades. A lack of standardization in monitoring severely constrains the analysis of peatland restoration outcomes. Increased funding for monitoring and reporting outcomes, and improved monitoring consistency, could greatly enhance our understanding of peatland restoration ecology and improve practice.

A large-scale and long-term experiment to identify effectiveness of ecosystem restoration

“…S8). Altogether these changes resulted in drier, more heath forest like conditions in drained sites, highlighting that drained sites do not necessarily recover passively without restoration 41 . Detecting the continuous degradation with our experiment is somewhat remarkable because the sites had been drained as long as 50-60 years ago, and only in three sites the ditches have been re-opened since.…”

Perfectly imperfect and muddling through for sustainable futures

“…Within 56 of these sites, there are over 8,000 hectares of deep peat suitable for "enhanced" rehabilitation, i.e. sphagnum moss inoculation -14,000 hectares of peatlands have already been rehabilitated (EU LIFE monitoring visit 2023; Allan et al, 2023). This level of overall coverage and density of inoculation provides the best balance for an accelerated transition to fully functioning peatland.…”