Estimations of GHG emissions from drained peatlands: Accountability in the trans-border Neman River basin

The EU Green Deal outlines a comprehensive strategy and policies to transform Europe into a resource-efficient and competitive economy, intending to achieve net-zero greenhouse gas (GHG) emissions by 2050. Although peatlands have been identified as a substantial source of GHGs, we still require harmonized emission factors (EFs) to accurately calculate GHG fluxes from European peatlands used in agriculture and forestry.

This paper attempts to estimate large-scale GHG emissions from peatlands in the trans-border Neman River basin (NRB), by (I) providing a comprehensive overview of the extent and distribution of peatlands within the Neman River basin, (II) delivering new emission estimates based on current land use categories and more site-specific emission factors, (III) establishing a knowledge base to support the derivation of region-specific emission factors and (IV) identifying high-emission peatland land use areas by targeted for restoration to inform strategic mitigation planning.

Results estimate 22 (11-36) Mt CO₂eq year^-1 are emitted from the NRB peatlands. The highest median emissions were estimated for Belarus, with 11.3 Mt CO₂eq year^-1, followed by Lithuania at 9.7 Mt CO₂eq year^-1, Poland at 0.46 Mt CO₂eq year^-1, and Russia (Kaliningrad Oblast) at 0.037 Mt CO₂eq year^-1. For undrained peatlands, forests emit the highest amount, totalling a median estimation of 2.7 Mt CO₂eq year^-1. For drained peatlands, grasslands emit the highest median value 8.2 Mt CO₂eq year^-1, followed by croplands 7.0 Mt CO₂eq year^-1, peatland forests 2.4 Mt CO₂eq year^-1, and peat mines 0.86 Mt CO₂eq year^-1.

This study identified that NIRs are underestimating GHG emissions. Individual countries in the NRB use outdated Intergovernmental Panel on Climate Change (IPCC) EFs and do not seek their own EFs, reflecting local bio-ecological conditions and differences in peatland management practices. We recommend that countries in the NRB apply the same harmonized EFs for comparable ecoregions.