Img 5771  Soileffects

Effects of Anaerobically Digested Manure on Soil Fertility. The Field Experiment “SoilEffects”

Since 2011, grass-clover yields and soil characteristics have been studied at Tingvoll farm, with application of digested and non-digested slurry from organic dairy cows. Results are available below.

The Tingvoll farm’s biogas plant has been in operation since 2012. For organic farmers it is important to know if digested slurry could be harmful or less beneficial to soil life than normally treated livestock manure. Maintaining a fertile soil is the basis of organic agriculture, and an active and diverse soil fauna is thus needed to release plant-available nutrients. Producing biogas can contribute to a farm’s energy self-sufficiency and reduce methane emissions from slurry storage. On the other hand, the organic carbon in the manure that is converted to biogas could perhaps have served as food for the soil fauna instead? What should organic farmers actually think about anaerobic digestion of livestock slurry? We are trying to provide some answers in a long-term field experiment called «SoilEffects».

The field trials are included in the Tingvoll farm’s crop rotation, with low manure application rates corresponding to organic farming, and high rates equal to those in conventional farming. A number of sources (see below) have co-funded the field experiments since 2011. In 2016, the Regional Research Fund of Mid-Norway and Onya Hustadmarmor will become important funding sources <lenke til egen omtale av Marmorfiks>, since the experimental plots will also be used to study the effect of fine-ground limestone added to the manure prior to application. These trials are an arena for improving our knowledge, while at the same time enabling us to obtain long-term registrations of yields and soil characteristics under different manuring regimes.

Img 5782  Soileffects (Photo: Reidun Pommereche)
(Photo: Reidun Pommereche)

Project details (1)

Project coordinator:Anne-Kristin Løes
Project staff NORSØK:Reidun Pommeresche
Project partners: Anders Johansen (Aarhus University), Hugh Riley, (NIBIO), Paul Mäder (FiBL) and Maud Grøtta (Norwegian Agricultural Extension Service)
Funding:Research Council of Norway (BIONAER programme), research funds allocated via the national agricultural agreement, Ministry of Agriculture and Food, Norwegian Agriculture Agency, Møre og Romsdal County Council, NORSØK and Sparebanken Møre
Project period: