Abstract: MACSUR — Modelling European Agriculture with Climate Change for Food Security — is a  knowledge hub that was formally created in June 2012 as a European scientific network.  The strategic aim of the knowledge hub is to create a coordinated and globally visible  network of European researchers and research groups, with intra- and interdisciplinary  interaction and shared expertise creating synergies for the development of scientific  resources (data, models, methods) to model the impacts of climate change on agriculture  and related issues. This objective encompasses a wide range of political and sociological  aspects, as well as the technical development of modelling capacity through impact  assessments at different scales and assessing uncertainties in model outcomes. We achieve  this through model intercomparisons and model improvements, harmonization and  exchange of data sets, training in the selection and use of models, assessment of benefits  of ensemble modelling, and cross-disciplinary linkages of models and tools. The project  engages with a diverse range of stakeholder groups and to support the development of  resources for capacity building of individuals and countries. Commensurate with this broad  challenge, a network of currently 300 scientists (measured by the number of individuals on  the central e-mail list) from 18 countries evolved from the original set of research groups  selected by FACCE.   In the spirit of creating and maintaining a network for intra- and interdisciplinary  knowledge exchange, network activities focused on meetings of researchers for sharing  expertise and, depending on group resources (both financial and personnel), development  of collaborative research activities. The outcome of these activities is the enhanced  knowledge of the individual researchers within the network, contributions to conference  presentations and scholarly papers, input to stakeholders and the general public, organised  courses for students, junior and senior scientists. The most visible outcome are the  scientific results of the network activities, represented in the contributions of MACSUR  members to the impressive number of more than 200 collaborative papers in peer-reviewed  publications.   Here, we present a selection of overview and cross-disciplinary papers which include  contributions from MACSUR members. It highlights the major scientific challenges  addressed, and the methodological solutions and insights obtained. Over and above these  highlights, major achievements have been reached regarding data collection, data  processing, evaluation, model testing, modelling assessments of the effects of agriculture  on ecosystem services, policy, and development of scenarios. Details on these  achievements in the context of MACSUR can be found in our online publication FACCE  MACSUR Reports at http://ojs.macsur.eu.

Abstract: The dairy sector may expand by over 2% per annum with expiration of the milk quota system in countries with a major and intensive dairy sector. Such expansion will increase pressure to further reduce on-farm nitrogenous emission per unit of milk produced even more. A straightforward N-reducing measure is the manipulation of the cow diet resulting in a lower excretion of ammoniacal N excreted with urine in particular. However, dietary N-reducing measures also affect enteric methane emissions and P excretion. For an integral evaluation of the consequences of N-reducing dietary measures on on-farm emissions, the trade-offs between N emissions and P and methane emissions at the cow level need to be taken into account. Therefore, a simulation study was performed to simulate the consequence of various N-reducing and/or P-reducing dietary measures (altered grassland management, grass silage replaced by low-N feeds, increased concentrate allowance) on enteric methane emission and on N and P excretion. Results indicate a large scattering, but there was a trend of higher methane emissions with lower N excretion was significant. Specific measures had a synergistic effect on emissions such as the exchange of maize for grass silage. The present detailed model evaluations may aid in quantifying the extent of trade-offs between various types of emissions at the cow level, but also prove to be relevant when evaluating consequences of management options taken at the farm scale. No Label