The project will utilize know-how from ongoing field trials around Europe to investigate how different cultivation strategies, like crop rotation and soil tillage, affect soil fertility and weed development. For producers, a simple tool for strategic planning of measures that can improve soil fertility in plant production will be developed.

Nitrogen dynamics, carbon sequestration and emission of greenhouse gases are important elements in the contribution from the Norwegian research group. We are currently gathering data on relevant crop rotations in European regions. It is still early in the project period, so we do not have results so far.

Technical notes and audio-visual material directed at practitioners will be produced in English and may be translated and adapted to national conditions by project partners for the following tools: Spade diagnosis, earthworm and slug sampling, residue decomposition (tea-bag test) and soil respiration, visual observations of nodule activity on legumes, decision support tool (HighCrop).

The Norwegian research group coordinated by Randi B. Frøseth is leading a work package on N losses, C gains, and greenhouse gas emissions.

The project involves participants from 12 European countries. In work package 5, which is coordinated from Norway, we cooperate with Christine Watson and Maria Stenberg SLU Sweden, Jørgen Olesen AU Denmark, Jordi Doltra CIFA Spain, Jaroslaw Stalenga IUNG and Ton Bars FSK Poland, and Marjetka Suhadolc UL Slovakia.

Task 1:Review and systematize knowledge on the effect of fertility building measures on C- and N-dynamics

• What do organic rotations look like in different climatic and agronomic zones across Europe, how efficiently do they use N and what is the long time effect on C and N (content and fractions in soil, leaching and gaseous losses)?
• What is the short term effect of grass/clover ley, when herbage is either harvested or mulched, on N-availability for the succeeding crop in different climatic zones in Europe?
• What is the effect of reduced tillage and/or controlled traffic on N-availability in different climatic zones in Europe?

Task 2:Identify main course of N2O emissions from organic crop rotations

• How is the concentration of easily degradable C- and N-sources in the top soil layer affected by fertility building measures normally used in organic crop rotations?
• How will increased concentration of easily degradable C- and N-sources in the top soil layer affect N2O emissions from crop rotations dominated by arable farming, and adapted to organic farming practice?
• Which measures can be implemented to reduce the risk of N2O emission without reducing plant yields in such systems?

Task 3:A technical note on visual observations of nodules on legumes