Catchment-based approach for water table management with irrigation for cultivated peatlands
Year: 2025
Type: article
Abstract: Controlled drainage and sub-irrigation have been proposed to enable shallow-drained agriculture in organic soils and mitigate greenhouse gas (GHG) emissions from intensively cultivated peatlands. However, the effects of current drainage practices on peatland water table depth (WTD) and the potential of using runoff from upstream catchment areas to adjust WTD in boreal peatlands are still poorly understood. To address these issues, WTD monitoring was initiated in 13 cultivated peatlands with different drainage systems in the flat western coastal region of Finland. For each field, we estimated the size of the upper catchment, median summer runoff sum, and mean 7-day low flow rate. The water required to reach a 30 cm target WTD was estimated from peat specific yield. Fields with old subsurface drainage, new subsurface drainage, and open ditch drainage had average WTD of 0.51 m, 0.82 m, and 0.95 m, respectively, during the two monitoring years (11/2022 – 10/2024). Each 10 cm decrease in mean WTD was estimated to require an average of 13.2 mm of additional water. The average summer runoff sum from the upper catchment was sufficient to reach any target WTD, but the summer low-flow did not fulfil the daily irrigation requirements. Most runoff is available during early summer, thus creating a timing challenge with water availability, even in regions with excess annual precipitation. This highlights the importance of catchment-scale management for GHG mitigation. In this study, we propose a generally applicable framework to link peatland GHG mitigation with water resources and catchment-scale management.
Source: Agricultural Water Management
Institutions: Natural Resources Institute Finland, University of Oulu
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,070
Award: G2209326439
OpenAlex ID: W4408346832