Ecological resilience of restored peatlands to climate change

Abstract

Degradation of peatlands through land-use change and drainage is currently responsible for 5-10% of global annual anthropogenic carbon dioxide emissions. Therefore, restoring disturbed and degraded peatlands is an emerging priority in efforts to mitigate climate change. While restoration can revive multiple ecosystem functions, including carbon storage, the resilience of restored peatlands to climate change and other disturbances remains poorly understood. Here, we review the recent literature on the response of degraded and restored peatlands to fire, drought and flood. We find that degraded sites can generally be restored in a way that allows for net carbon sequestration. However, biodiversity, hydrological regime, and peat soil structure are not always fully restored, even after a decade of restoration efforts, potentially weakening ecosystem resilience to future disturbances. As the recovery of degraded peatlands is fundamental to achieving net-zero goals and biodiversity targets, sound science and monitoring efforts are needed to further inform restoration investments and priorities.

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

“…Our findings suggest that the recovery of peatland vegetation cover toward that of intact sites is typically a long‐term process, spanning multiple decades, reemphasizing the need to conserve existing pristine peatlands (Loisel & Gallego‐Sala 2022). Importantly, our findings also indicate that more intense restoration interventions can accelerate positive outcomes.…”

“…We therefore focused our study on the Northern Hemisphere's temperate and boreal peatlands, comprising bogs and fens with peat-forming Sphagnum mosses as keystone species and ecosystem engineers (Van Breemen 1995;Rochefort 2000;Caporn et al 2018), and with other temperate and boreal peatland specialist plants. The successful restoration of peatlands and associated ecosystem services requires the recovery of characteristic, self-regulatory peat-forming vegetation (Rochefort 2000;Littlewood et al 2010).…”

“…To ensure the effective deployment of future restoration and the investment underpinning it, it is crucial that restoration outcomes are understood (Parry et al 2014;Rochefort & Andersen 2017). Vegetation change, the focus of this paper, is often monitored as a principal determinant of peatland functionality, including carbon sequestration (Holden et al 2011;Swenson et al 2019), with the regeneration of Sphagnum coverage, a key indicator for potential peat formation (Rochefort 2000;Poulin et al 2012;Lindsay et al 2014). Sphagnum mosses are sensitive to water-table changes (Rydin & Jeglum 2013), thus also acting as proxies for hydrodynamics.…”

Sphagnum mosses, the impact of disturbances and anthropogenic management actions on their ecological role in CO2 fluxes generated in peatland ecosystems

“…Despite the significant ecosystem services provided by peatlands, it is estimated that 15-20% of their global extent has experienced degradation processes due to anthropogenic disturbances (Joosten, 2009;Joosten & Clarke, 2002;Ma et al, 2022;Parish et al, 2008;Urák et al, 2017;Waddington et al, 2015), generating 5-10% of annual global anthropogenic CO 2 emissions (Friedlingstein et al, 2014;Loisel & Gallego-Sala, 2022). Human pressures have transformed the biogeochemical functionality of peatlands from a C sink in the long term to CO 2 emitters in the short term (Evrendilek, 2014;Munir et al, 2015;Page et al, 2022).…”

Post‐fire peatland recovery by peat moss inoculation depends on water table depth

“…Considering ongoing increases in atmospheric carbon and rising global temperatures, a rapid return of typical peatland vegetation is crucial to minimise the loss of previously locked‐up carbon (Nugent et al, 2019). The restoration of peatland vegetation and subsequent ecohydrological processes can also enhance the resistance and resilience of restored peatlands and minimise carbon loss to future extreme climatic events (Blier‐Langdeau et al, 2022; Loisel & Gallego‐Sala, 2022). Consequently, additional restoration action may be necessary along with rewetting to push restored peatlands towards pre‐disturbed states and ensure the long‐term stability of restored peatlands (Granath et al, 2016).…”