Abstract: The report presented here provides an inventory of reports and conference papers  produced by the partners of the livestock and grassland modelling theme (LiveM) of the  Modelling European Agriculture with Climate Change for Food Security (MACSUR)  knowledge hub. The findings presented illustrate the diverse nature of the multidisciplinary  LiveM research community, and provide a reference source for those seeking  to identify and pull out farm-level modelling outputs from the work of MACSUR and its  partners. The survey of farm-scale outputs from LiveM revealed the interdependent, dual  role of a knowledge hub: to increase the capacity of modelling to meet stakeholder and  societal needs under climate change, and to apply that increased capacity to provide new  understanding and solutions at the policy and (the focus here) farm scale. While capacity  building work across disciplines is time-consuming, difficult, and to a large extent invisible  to stakeholders, such work is vital to ensuring that subsequent scientific outcomes reflect  best practice, and integrated expertise. Long term, sustained funding of network-based  capacity building activities is highlighted as essential to ensuring that the farm-scale  modelling work highlighted here can continue to build on ongoing improvements in model  quality, flexibility and stakeholder relevance.

Abstract: The increasing global demand for food requires a sustainable intensification of crop production in low-yielding areas. Actions to improve crop production in these regions call for accurate spatially explicit identification of yield gaps, i.e. the difference between potential or water-limited yield and actual yield. The Global Yield Gap Atlas (GYGA) project proposes a consistent bottom-up approach to estimate yield gaps. For each country, a climate zonation is overlaid with a crop area map. Within climate zones with important crop areas, weather stations are selected with at least 10 years of daily data. For each of the 3 dominant soil types within a 100 km zone around the weather stations, the potential and water-limited yields are simulated with the WOFOST crop model, using location-specific knowledge on crop systems. Data from variety trials or other experiments, approaching potential or water-limited yields, are used for validation and calibration of the model. Actual yields are taken from sub-national statistics. Yields and yield gaps are scaled up to climate zones and subsequently to countries. The average national simulated wheat yields under rainfed conditions varied from around 5 to 6 t/ha/year in the Mediterranean to nearly 12 t/ha/year on the British Isles and in the Low Countries. The average actual wheat yield varied from around 2 to 3 t/ha/year in the Mediterranean and some countries in East Europe to nearly 9 t/ha/year on the British Isles and in the Low Countries. The average relative yield gaps varied from around 10% to 30% in many countries in Northwest Europe to around 50% to 70% in some countries in the Mediterranean and East Europe. The paper will elaborate on results per climate zone and soil type, and will also include barley and maize. Furthermore we will relate yield gaps to nitrogen use.