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Plant phenology, which describes the timing of plant development, is a major aspect of plant response to environment and for crops, a major determinant of yield. Many studies have focused on comparing model equations for describing how phenology responds to climate but the effect of crop model calibration, also important for determining model performance, has received much less attention. The objectives here were to obtain a rigorous evaluation of prediction capability of wheat phenology models, to analyze the role of calibration and to document the various calibration approaches. The 27 participants in this multi-model study were provided experimental data for calibration and asked to submit predictions for sites and years not represented in those data. Participants were instructed to use and document their “usual” calibration approach. Overall, the models provided quite good predictions of phenology (median of mean absolute error of 6.1 days) and did much better than simply using the average of observed values as predictor. The results suggest that calibration can compensate to some extent for different model formulations, specifically for differences in simulated time to emergence and differences in the choice of input variables. Conversely, different calibration approaches were associated with major differences in prediction error between the same models used by different groups. Given the large diversity of calibration approaches and the importance of calibration, there is a clear need for guidelines and tools to aid with calibration. Arguably the most important and difficult choice for calibration is the choice of parameters to estimate. Several recommendations for calibration practices are proposed. Model applications, including model studies of climate change impact, should focus more on the data used for calibration and on the calibration methods employed.

Rainfed cereals are the main staple food crops in the West African Sudan Savannah. While current yield levels are low due in large part to the limited use of fertilisers, sus-tainable intensification of cropping systems is widely promoted in the region to im-prove food security and drive regional economic development. However, an important consideration is increased internannual yield variability and possible interactions with climate change, as this represents an important source of risk for farmers. This study assessed the effect of intensification on maize, pearl millet and sorghum yields under 1.5°C and 2.0°C global warming in the West African Sudan Savannah. Simulations were conducted with two crop models (DSSAT and Lintul5 embedded into the SIM-PLACE modelling framework) at a spatial resolution of 0.25° under both current fer-tiliser use and optimum fertiliser application (intensification case). The models were calibrated with local varieties from field experiments in the region with management reflecting a range of typical sowing windows. Results indicated that yields simulated under intensification were two to three times higher than yields simulated under cur-rent fertiliser use, irrespective of the warming scenario. However, yield losses under climate change were slightly higher with intensification: 2 % units higher for maize and sorghum with 2.0°C compared to 1.5°C warming, with no change in millet yields for either scenario. As expected, interannual variability increased with intensifica-tion compared to current fertiliser use, though there was no interaction with climate change scenario. In summary, it is suggested that intensification would much more than offset the negative impacts of climate change, though economics analysis is re-quired to understand the implications for risk and constraints on market development needed to support intensification.

With the Paris Agreement, governments around the world agreed to limit global temperature rise to less than 2.0°C above pre-industrial levels, with the ambition to keep warming to 1.5°C. Designing appropriate mitigation responses requires weighing costs of mitigating versus associated damages for the two levels of warming, with particular consideration of the implications for regions already challenged by food insecurity. This study assessed impacts in the West African Sudan Savanna of 1.5°C versus 2.0°C on yields of maize, pearl millet and sorghum. Two crop models were used that were calibrated with common varieties from experiments in the region. To capture a range of realistic management, early, typical and late sowing was assessed. Further, simulations were conducted for both current fertilizer rates and for an intensification case which assumed fertility not limiting, in attempt to capture the extremes of possible economic development scenarios on current cropping systems. With current fertilizer use, results indicated 2% units higher losses for maize and sorghum with 2.0°C compared to 1.5°C warming, with no change in millet yields for either scenario. In the intensification case, yield losses due to climate change were larger than with current fertilizer levels. However, despite the larger losses, yields were always 2-3 times higher with intensification, irrespective of the warming scenario. Though yield variability increased with intensification, there was no interaction with warming scenario. Risk and market analysis are needed to extend these results to understand implications for food security.

While simulation of cropping systems over a few years might reflect well the short term effects of management and cultivation, long term effects on soil properties and their consequences for crop growth and matter fluxes are not captured. Especially the effect on soil carbon sequestration/depletion is addressed by this task. Simulations of an ensemble of crop models are performed as transient runs over a period of 120 year using observed weather from three stations in Czech Republic (1961-2010) and transient long time climate change scenarios (2011-2080) from five GCM of the CMIP5 ensemble to assess the effect of different cropping and management systems on carbon sequestration, matter fluxes and crop production in an integrative way. Two cropping systems are regarded comprising two times winter wheat, silage maize, spring barley and oilseed rape. Crop rotations differ regarding their organic input from crop residues, nitrogen fertilization and implementation of catch crops. Models are applied for two soil types with different water holding capacity. Cultivation and nutrient management is adapted using management rules related to weather and soil conditions. Data of phenology and crop yield from the region of the regarded crops were provided to calibrate the models for crops of the rotations. Twelve models were calibrated in this first step. For the transient long term runs results of four models were submitted so far. Outputs are crop yields, nitrogen uptake, soil water and mineral nitrogen contents, as well as water and nitrogen fluxes to the atmosphere and groundwater. Changes in the carbon stocks and the consequences for nitrogen mineralisation, N fertilization and emissions also considered.

Nature conservation has a long tradition in the South Caucasus, a region with very high biodiversity. Alongside century old nature reserves (NR) in Azerbaijan and Georgia, two new transboundary national parks (NP) have recently been created in Armenia and Georgia. All of these protected areas exert an influence on the local populations, which use land located inside or in proximity to these areas. To investigate the impact of protected areas on the local populations, we conducted a qualitative study close to two neighbouring, historical NRs in Georgia (Lagodekhi) and Azerbaijan (Zaqatala), and close to the two new transboundary NPs in Armenia (Lake Arpi) and in Georgia (Javakheti). We collected the opinions of the local populations, local administrations, and environmental NGOs regarding the impact of protected areas on the livelihoods of the local populations and investigated whether the local populations developed strategies for dealing with these impacts. Results show that the land use restrictions entailed by protected areas cause conflicts of interests between the goals of conservation and those of the local populations on the one hand, and competition between different local groups with regard to scarce resources such as pastures on the other hand. These land use restrictions are due to the land use regulations of the protected areas and concern the use of pastures and forests. All sorts of tourism could provide a possible solution to settle conflicts and to increase incomes.

Nature conservation has a long tradition in the South Caucasus, a region with very high biodiversity. Alongside century old nature reserves (NR) in Azerbaijan and Georgia, two new transboundary national parks (NP) have recently been created in Armenia and Georgia. All of these protected areas exert an influence on the local populations, which use land located inside or in proximity to these areas. To investigate the impact of protected areas on the local populations, we conducted a qualitative study close to two neighbouring, historical NRs in Georgia (Lagodekhi) and Azerbaijan (Zaqatala), and close to the two new transboundary NPs in Armenia (Lake Arpi) and in Georgia (Javakheti). We collected the opinions of the local populations, local administrations, and environmental NGOs regarding the impact of protected areas on the livelihoods of the local populations and investigated whether the local populations developed strategies for dealing with these impacts. Results show that the land use restrictions entailed by protected areas cause conflicts of interests between the goals of conservation and those of the local populations on the one hand, and competition between different local groups with regard to scarce resources such as pastures on the other hand. These land use restrictions are due to the land use regulations of the protected areas and concern the use of pastures and forests. All sorts of tourism could provide a possible solution to settle conflicts and to increase incomes. Naturschutz hat eine lange Tradition im Südkaukasus, einer Region, die sich durch eine hohe Biodiversität auszeichnet. Neben über hundert Jahre alten Naturschutzgebieten in Aserbaidschan und in Georgien wurden kürzlich zwei neue grenzübergreifende Nationalparks in Armenien und Georgien eingerichtet. Alle diese Schutzgebiete haben Auswirkungen auf die lokale Anrainerbevölkerung, welche Land innerhalb oder in der Nähe dieser Gebiete nutzt. Um die Auswirkungen von zwei benachbarten, historischen Schutzgebieten in Georgien (Lagodekhi) und in Aserbaidschan (Zaqatala) sowie von zwei neuen grenzübergreifenden Nationalparks in Armenien (Lake Arpi) und in Georgien (Javakheti) auf die lokale Bevölkerung zu untersuchen, führten wir eine qualitative Studie durch. Zentrale Fragestellungen der Studie betrafen zum einen die Ansichten der lokalen Bevölkerung, der lokalen Verwaltung und von Umwelt-Nichtregierungsorganisationen hinsichtlich der Auswirkungen von Schutzgebieten auf den Lebensunterhalt der Anrainerbevölkerung und zum anderen mögliche Strategien der Anrainerbevölkerung für den Umgang mit den Auswirkungen der Schutzgebiete. Die Ergebnisse zeigen, dass Landnutzungsbeschränkungen, die durch die Schutzgebiete hervorgerufen werden, einerseits Interessenkonflikte zwischen den Zielen des Naturschutzes und den Zielen der Anrainerbevölkerung hervorrufen können, und andererseits Rivalitäten zwischen verschiedenen lokalen Gruppen in Bezug auf knappe Ressourcen wie Weideland. Landnutzungsbeschränkungen sind eine Folge der Landnutzungsbestimmungen der Schutzge und betreffen den Zugang zu Weideland und Wäldern. Verschiedene Arten von Tourismus könnten eine mögliche Lösung darstellen, um bestehende Konflikte zu lösen und um die Einkommen der lokalen Bevölkerung zu verbessern.