Abstract: Rather than on crop modelling only, climate change impact assessments in agriculture  need to be based on integrated assessment and farming systems analysis, and account for  adaptation at different levels. With a case study for Flevoland, the Netherlands, we  illustrate that 1) crop models cannot account for all relevant climate change impacts and  adaptation options, and 2) changes in technology, policy and prices have had and are likely  to have larger impacts on farms than climate change. While crop modelling indicates  positive impacts of climate change on yields of major crops in 2050, a semi-quantitative  and participatory method assessing impacts of extreme events shows that there are  nevertheless several climate risks. A range of adaptation measures are, however, available  to reduce possible negative effects at crop level. In addition, at farm level farmers can  change cropping patterns, and adjust inputs and outputs. Also farm structural change will  influence impacts and adaptation. While the 5th IPCC report is more negative regarding  impacts of climate change on agriculture compared to the previous report, also for  temperate regions, our results show that when putting climate change in context of other  drivers, and when explicitly accounting for adaptation at crop and farm level, impacts may  be less negative in some regions and opportunities are revealed. These results refer to a  temperate region, but an integrated assessment may also change perspectives on climate  change for other parts of the world. No Label

Abstract: Cropping systems are affected by climate change because of the strong relationship between crop development, growth, yield, CO2 atmospheric concentration and climate conditions. The increasing temperatures and the reduction of available water resources may result in negative impacts on the agricultural activity in Mediterranean environments than other areas. In this study the CERES-Wheat and CROPGRO-Tomato models were used to assess the effects of climate change on winter wheat (Triticum durum L.) and processing tomato (Lycopersicon aesculentum Mill.) in one of most productive areas of Italy, located in the northern part of the Puglia region. In particular we have compared three different General Circulation Models (HadCM3, CCSM3, ECHAM5) subjected to a statistical downscaling under two future IPCC scenarios (B1 and A2). The analysis was carried out at regional scale repeating the simulations for seven homogeneous area characterizing the spatial variability of the region. In the second part of the study, considering only HadCM3 data set, climate change impact on long-term sequences of the two crops combined in three crop rotations were evaluated in terms of yield performances and soil fertility as indicated by the soil organic content of carbon and nitrogen. The comparison between GCMs showed no significant differences for winter durum wheat yield, while noticeable differences were found for yield and irrigation requirements of tomato. Under future scenarios, the production levels were reduced for tomato, whereas positive yield effects were observed for winter durum wheat. For winter durum wheat the simulation indicated that two- and three-year rotations, including one year of tomato cultivation, improved the cereal yield and this positive effect maintained its validity also in future scenarios. For both crops higher requirements of water and nitrogen were predicted under future scenarios. This result coupled with the decrease of yield caused negative reduction of water use efficiency and nitrogen use efficiency for tomato cultivation.