Abstract: Adaptation of agricultural systems to climate uncertainties requires the construction of scenarios that should take into account the complexities of socio-ecological systems of a specific local context. Adaptation scenarios of agricultural systems are not making forecasts or predictions, but prospective futures or future paths. They can facilitate our understanding of how systems work and evolve. Adaptation processes of agricultural systems involve a variety of changes in local practices and social organization. The development of adaptation scenarios at farm level entails a clear understanding of farmers’ frames that are mediated by their interests, experiences and internal and external forces. Farmers’ frames is the way in which farmers frame climate issues emphasizing vulnerabilities, uncertainties and opportunities (i.e: impacts on their farming systems) and open the window for searching adaptation strategies. This study reports on the methodologies for the development of explorative scenarios (i.e., scenarios that explore the future from a variety of perspectives) for the climate change adaptation of four agricultural systems (intensive dairy cattle, extensive dairy sheep, rice farming and horticulture) in the Oristano regional pilot study in Italy. Explorative scenarios were used to explore trends into the future from the past and present. Three research steps were followed: (i) in the first step farmers’ perceptions and prospective through semi-structured interviews and questionnaires were analysed; (ii) in the second step the evolution of the agricultural systems (i.e. temporal and spatial) was evaluated; (iii) the third step examined multiple stakeholders’ outlooks about farm-level possible adaptive strategies through interactive workshops.

Abstract: Crop models can be sensitive to climate input data aggregation and this response may differ among models. This should be considered when applying field-scale models for assessment of climate change impacts on larger spatial scales or when coupling models across scales. In order to evaluate these effects systematically, an ensemble of ten crop models was run with climate input data on different spatial aggregations ranging from 1, 10, 25, 50 and 100 km horizontal resolution for the state of North Rhine-Westphalia, Germany. Models were minimally calibrated to typical sowing and harvest dates, and crop yields observed in the region, subsequently simulating potential, water-limited and nitrogen-limited production of winter wheat and silage maize for 1982-2011. Outputs were analysed for 19 variables (yield, evapotranspiration, soil organic carbon, etc.). In this study the sensitivity of the individual models and the model ensemble in response to input data aggregation is assessed for crop yield. Results show that the mean yield of the region calculated from climate time series of 1 km horizontal resolution changes only little when using climate input data of higher aggregation levels for most models. However, yield frequency distributions change with aggregation, resembling observed data better with increasing resolution. With few exceptions, these results apply to the two crops and three production situations (potential, water-, nitrogen-limited) and across models including the model ensemble, regardless of differences among models in simulated yield levels and spatial yield patterns. Results of this study improve the confidence of using crop models at varying scales.

Abstract: Data of diverse crop rotations from five locations across Europe were distributed to modelers to investigate the capability of models to handle complex crop rotations and management interactions. Crop rotations comprise various main crops (winter/spring wheat, winter/spring barley, rye, oat, maize, sugar beet, oil seed rape and potatoes) plus several catch crops. The experimental setup of the datasets included treatments such as modified soils, crops exchanged within the rotations, irrigation/rainfed, nitrogen fertilization, residue management, tillage and atmospheric CO2 concentration. 19 modeling teams registered to model either the whole rotation or single crops. Models which are capable to run the whole rotation should provide transient as well as single year simulations with a reset of initial conditions. In the first step only initial soil conditions (water and soil mineral N) of the first year and key phenological stages were provided to the modelers. For calibration, crop yields and biomass were provided for selected years but not for all seasons. In total the combination of treatments and seasons results in 301 years of simulation. Results were analyzed to evaluate the effect of transient simulation versus single-year simulation regarding crop yield, biomass, water and nitrogen balance components. Model results will be evaluated crop-specifically to identify crops with highest uncertainty and potential for model improvement. Full data will be provided to modelers for model-improvement and results will provide insights into model capabilities to reproduce treatments and crops. Further, the question of error propagation along the transient simulation of crop rotations will be addressed.