Efficient use of different sources of nitrogen in agriculture – from theory to practice
Nitrogen is one of the most important inputs in crop production and efficient use of N sources is the basis for combining future food security and minimized negative environmental impact. Nitrogen is easily lost from the agricultural system, thereby contributing to pollution of ground and surface waters and climate change. In this workshop we will discuss how nitrogen use efficiency of different available nitrogen sources can be improved, to secure food production and minimize losses. We will discuss system approaches at farm level (topic I) as well as fine tuning of management using new technology (topic II). We will also discuss how implementation of more nitrogen efficient management (topic III) can be achieved and how we can measure and model the effects at different scales (topic IV).

I Nitrogen dynamics in different farming systems
– What we can learn from different types of farming systems (good and bad)
– N use efficiency in the long-term perspective
– The role of the crop rotation for high N efficiency
– Catch crops, cover crops and intercropping
– New choices of crops and varieties for improved N use efficiency
– Role of legumes for N supply
– Efficient use of different types of N sources
– Increasing N efficiency in animal production systems

II Precision Nitrogen Management
– Mapping and management of within field variability
– Crop and soil measurements for estimating N fertilization requirements
– Real time and web based modeling of N requirements
– Manure treatments for optimizing N fertilizer efficiency
– Application strategies for different types of N sources
– Management of organic residues for timing of N availability with crop demand
– Measures to reduce leaching and gas emissions

III Knowledge transfer and implementation
– Farmer directed research, methods and results
– Participatory learning and action
– Instruments for implementation of measures
– Advisory approaches
– Decision support tools for N management
– From the farmers point of view

IV Nitrogen processes at different scales
– Biogeochemical and biological processes
– Modeling and monitoring nitrogen leaching and gas emissions
– N flows on regional and global scale
– Improving regional/national scale N efficiency