EGU23-13830, updated on 09 Jan 2024
EGU General Assembly 2023
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.

Nitrogen losses from drained temperate agricultural peatland after mineral soil coverage

Yuqiao Wang1,2, Sonja Paul1, Christine Alewell2, and Jens Leifeld1
Yuqiao Wang et al.
  • 1Agroscope, Climate and Agriculture group, Zürich, Switzerland (
  • 2University of Basel, Environmental Geoscience, Basel, Switzerland

Drainage for agriculture induces peatland decomposition, subsidence, and nitrogen (N) losess, thereby contributing to climate change. In order to maintain the productivity of agricultural managed peatland, and to counteract soil subsidence, mineral soil coverage is becoming an increasingly used practice in Switzerland and other European countries. Mineral soil coverage may change the N balance from the corronsponding organic soil. To explore the effect of this practice on the N flow within the plant – soil system and the N loss, we carried out a field experiment on a peatland in the Swiss Rhine Valley that was managed as an intensive meadow. The peatland was divided into two parts, either without (Ref) or with mineral soil coverage, thickness ~ 40 cm (Cov). In this experiment, 15NH415NO3 were applied on field plots to follow the recovery of 15N in grass, root, and soil over 11 months. The 15N that was not recovered was designated as lost via leaching or gaseous emissions. Soil N mineralization was measured in a laboratory incubation. And the gaseous N loss as N2O was determined by automatic time integrating chamber systems (ATIC) over two years. The experimental results showed that the total 15N loss from Cov was lower (p < 0.05) than from Ref, even though plant 15N uptake did not vary between the two sites. The lower net N loss from the Cov site was accompanied by higher soil 15N retention in the soil. The laboratory incubation revealed a ~2 times higher specific N release per unit soil N at Cov than at Ref, suggesting a faster SOM turnover rate at Cov. Regarding the N loss as N2O, emissions from Ref were at the upper end of previously measured fluxes in drained peatland. In contrast, N2O emissions from Cov were reduced by a factor of nine over two years. Overall, the mineral soil cover increased the retention of fertilizer-N in the soil, thus reducing the system N losses, especially N loss as N2O emissions. Our results indicate agricultural production on drained peatland is less harmful to the environment with mineral soil coverage than using drained peatland directly. 

How to cite: Wang, Y., Paul, S., Alewell, C., and Leifeld, J.: Nitrogen losses from drained temperate agricultural peatland after mineral soil coverage, EGU General Assembly 2023, Vienna, Austria, 23–28 Apr 2023, EGU23-13830,, 2023.