Nitrogen Storage Change and δ15N Transitions of Peat Columns in Undrained and Forestry-drained Boreal Mires
Year: 2026
Type: article
Abstract: Peatland drying, driven by global warming and human impact alters nitrogen (N) cycling, potentially affecting gaseous and fluvial N fluxes, N stores in peat and in the underlying mineral subsoil, as well as the peat and subsoil N content and stable isotope ( 15 N/ 14 N) proportions (δ 15 N). Complete peat columns may reveal effects of past climatic periods and drainage for forestry on N stratigraphy within the peat. We measured N concentrations and δ 15 N values in peat and subsoil at undrained and drained peatlands in Finland. On three peatlands having paired natural and drained sites, we quantified changes in N, 15 N and 14 N storage, and calculated δ 15 N values of the lost or gained N for bog having three synchronous layers on undrained and drained sites. There was preferential downward transfer of 15 N in the uppermost peat of drained bog. Also, the subsoil beneath the drained fen had increased δ 15 N values compared to undrained site. δ 15 N values were generally below zero, except in one bog and in the subsoil under a fen. In peat layers dating to the Mid-Holocene, high dry bulk density, C%, N%, and humification index, coupled with low C/N ratio, were connected to the highest δ 15 N values in profile, similarly to those observed at the surface peat δ 15 N maxima. Drainage decreased total N content and transferred N from upper peat layers to deeper strata. In opposite to expectations, on peatlands having parallel undrained and drained sites, δ 15 N value increase or decrease was not connected clearly to decreased N mass.
Source: Wetlands
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDGs: Climate action, Life on land
Open Access status: hybrid
Estimated APC paid: $3,890
OpenAlex ID: W7130510867