Annual net CO 2 fluxes from drained organic soils used for agriculture in the hemiboreal region of Europe

作者：Arta Bārdule, Raija Laiho, Jyrki Jauhiainen, Kaido Soosaar, Andis Lazdiņš, Kęstutis Armolaitis, Aldis Butlers, Dovilė Čiuldienė, Andreas Haberl, Ain Kull, Milda Muraškienė, Ivika Ostonen, Gristin Rohula‐Okunev, Muhammad Kamil-Sardar, Thomas Schindler, Hanna Vahter, Egidijus Vigricas, Ieva Līcīte · 发表于：Biogeosciences · 年份：2025 · DOI：10.5194/bg-22-4241-2025 · 被引用次数：1 · 研究领域：Peatlands and Wetlands Ecology、Integrated Water Resources Management、Soil Carbon and Nitrogen Dynamics

Abstract. Carbon dioxide (CO2) emissions from drained organic soils used for agriculture contribute significantly to the overall anthropogenic greenhouse gas budget in the land use, land use change, and forestry (LULUCF) sector. To justify the implementation of climate change mitigation measures on these lands, it is important to estimate at least the regional variation in annual net CO2 fluxes. This study presents the first estimates of annual net CO2 fluxes from drained nutrient-rich organic soils in croplands (8 sites) and grasslands (12 sites) in the hemiboreal region of Europe, represented by Estonia, Latvia, and Lithuania. The study sites represented both deep and shallow highly decomposed, organic soils, categorised based on the concentration of organic carbon in the top 20 cm soil layer. CO2 flux measurements were conducted over at least 2 years at each site. To estimate annual net CO2 fluxes, ecosystem respiration (Reco) and soil heterotrophic respiration (Rhet) were measured using a manual dark-chamber technique, and carbon (C) input into soil through plant residues was estimated. Reco was strongly dependent on temperature, particularly soil temperature at 10 cm depth, but was rather independent of the soil water table level and soil moisture. The overall mean annual net soil CO2 fluxes, calculated as the difference between annual output (Rhet) and input (plant residues), were 4.8 ± 0.8 tCO2-Cha-1yr-1 for croplands and 3.8 ± 0.7 tCO2-Cha-1yr-1 for grasslands, while ...