Peatland restoration pathways to mitigate greenhouse gas emissions and retain peat carbon

Peatlands play a crucial role in the global
carbon (C) cycle, making their restoration a key strat-
egy for mitigating greenhouse gas (GHG) emissions
and retaining C. This study analyses the most com-
mon restoration pathways employed in boreal and
temperate peatlands, potentially applicable in tropical
peat swamp forests. Our analysis focuses on the GHG
emissions and C retention potential of the restoration
measures. To assess the C stock change in restored
(rewetted) peatlands and afforested peatlands with
continuous drainage, we adopt a conceptual approach
that considers short-term C capture (GHG exchange
between the atmosphere and the peatland ecosystem)
and long-term C sequestration in peat. The primary
criterion of our conceptual model is the capacity of
restoration measures to capture C and reduce GHG
emissions. Our findings indicate that carbon diox-
ide (CO 2) is the most influential part of long-term
climate impact of restored peatlands, whereas moder-
ate methane (CH4) emissions and low N 2O fluxes are
relatively unimportant. However, lateral losses of dis-
solved and particulate C in water can account up to a
half of the total C stock change. Among the restored
peatland types, Sphagnum paludiculture showed the
highest CO2 capture, followed by shallow lakes and
reed/grass paludiculture. Shallow lakeshore vegeta-
tion in restored peatlands can reduce CO 2 emissions
and sequester C but still emit CH4, particularly dur-
ing the first 20 years after restoration. Our concep-
tual modelling approach reveals that over a 300-year
period, under stable climate conditions, drained bog
forests can lose up to 50% of initial C content. In man-
aged (regularly harvested) and continuously drained
peatland forests, C accumulation in biomass and litter
input does not compensate C losses from peat. In con-
trast, rewetted unmanaged peatland forests are turning
into a persistent C sink. The modelling results empha-
sized the importance of long-term C balance analysis
which considers soil C accumulation, moving beyond
the short-term C cycling between vegetation and the
atmosphere.