(Frick, 21 June 2017) Positive effects on soil and climate can ensue when an organic farmer stops working with a plough. A FiBL trial gained these insights in clayey soils in Frick, Switzerland. Over the course of 13 years, about 8 % more humus formed in the soils tilled with a cultivator and skim plough compared to soil cultivation with a plough. In other words, reduced tillage sequestrates 2.3 tonnes of CO2 equivalents per ha more in a year than cultivation with a plough.
Farmland resembles a natural meadow
A plough mixes humus about 20 cm deep into the topsoil. In a reduced tillage system, however, more humus builds up in the topmost 10 cm. Below that threshold, the humus content remains stable or decreases. Thus, the distribution of humus in a reduced tillage system is closer to a meadow than a field. This can prevent soil erosion and increase the presence and variety of microorganisms like bacteria and fungi.
Greenhouse gases: Timing is more important than type of soil cultivation
Neither one of the examined crops grass-clover and winter wheat showed a difference in nitrous oxide emitted from the two systems. Methane emissions are at the same low level. However, the weather conditions have a huge influence. Tilling wet soils, whether performed with a plough or a cultivator, is not only ill advised for reasons of soil protection, but also due to the high nitrous oxide emissions.
- Maike Krauss, Department of Soil Sciences, FiBL Switzerland
- Hans-Martin Krause, Department of Soil Sciences, FiBL Switzerland
- Franziska Hämmerli, Communication, FiBL Switzerland
Information on reduced tillage
- bioaktuell.ch: For farmers (in German)
- fibl.org: For researchers (will be available in English soon)
Publications and articles
- Krauss, M., Ruser, R., Müller, T., Hansen, S., Mäder, P., Gattinger, A. (2017): Impact of reduced tillage on greenhouse gas emissions and soil carbon stocks in an organic grass-clover ley - winter wheat cropping sequence. Agriculture, Ecosystems & Environment 239, 324-333. doi: dx.doi.org/10.1016/j.agee.2017.01.029
- Availabe at: http://orgprints.org/31286/
- Krauss, M., Krause, H.-M., Spangler, S., Kandeler, E., Behrens, S., Kappler, A., Mäder, P., Gattinger, A. (2017): Tillage system affects fertilizer-induced nitrous oxide emissions. Biology and Fertility of Soils 53, 49-59. doi: 10.1007/s00374-016-1152-2
- Availabe at: http://orgprints.org/31140/
- Krauss, M., Perrochet, F., Lori, M., Ruser, R., Müller, T., Zikeli, S., Gruber, S., Claupein, W., Mäder, P., Gattinger, A. (2017): Reduzierte Bodenbearbeitung im Biolandbau – Klimaaspekte. Agrarforschung Schweiz, 8(6), 226–231.
- Coop Sustainability Fund
- Federal Office for Agriculture (FOAG) within the framework of a CORE Organic II project
- Swiss National Science Foundation (SNF) within the framework of NRP 68
- Federal Office for the Environment (FOEN)