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Bellocchi, G., Rivington, M., & Acutis, M. (2014). Deliberative processes for comprehensive evaluation of agro-ecological models. FACCE MACSUR Mid-term Scientific Conference, 3(S) Sassari, Italy.
Abstract: Biophysical models are acknowledged for examining interactions of agro-ecological systems and fostering communication between scientists, managers and the public. As the role of models grows in importance, there is an increase in the need to assess their quality and performance (Bellocchi et al., 2010). However, the heterogeneity of factors influencing model outputs makes it difficult a full assessment of model features. Where models are used with or for stakeholders then model credibility depends not only on the outcomes of well-structured statistical evaluation but also less tangible factors may need to be addressed using complementary deliberative processes. To expand our horizons in the evaluation of crop and grassland models, approaches have been reviewed with emphasis on using combined metrics. Comprehensive evaluation of simulation models was developed to integrate expectations of stakeholders via a weighting system where lower and upper fuzzy bounds are applied to a set of evaluation metrics. A questionnaire-based survey helped understanding the multi-faceted knowledge and experience required and the substantial challenges posed by the deliberative process. MACSUR knowledge hub holds potential to advance in good modelling practice in relation with model evaluation (including access to appropriate software tools), an activity which is frequently neglected in the context of time-limited projects.
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Persson, T., Kværnø, S., & Höglind, M. (2014). Determining the impact of soil regionalization and climate change on wheat and timothy grass yield in southeastern Norway. FACCE MACSUR Mid-term Scientific Conference, 3(S) Sassari, Italy.
Abstract: Southeastern Norway is characterized by variable soils, which affect its agricultural productivity. The region is dominated by cereal production, but livestock farming with forage crops has increased the latest years. Climate and socio-economic changes could entail a shift from the current production areas of cereal and forage crops. In this study we used the mechanistic models CSM-CERES and LINGRA to evaluate impacts of climate change and soil variability on wheat and timothy yields in Akerhus and Østfold Counties in Southeastern Norway. The models were run for historical (1961-90) and projected future (2046-2065) climatic conditions, and for four soil regionalizations of different resolution (1, 5, 16 and 76 representative soil profiles). The extrapolation of soil characteristics was based on similarities in texture, organic matter, layering and water holding capacity. Across the whole region, there were small differences in both spring wheat and timothy yield between the different soil regionalization resolutions. However, within certain districts within the region the differences in wheat grain yield and timothy biomass yield among the soil resolutions were up to 20 percent. These results indicate that a relatively detailed resolution of the soil proporties is preferred to better understand the impact of shifts in production between cereals and forage grasses on yield level if spatial variability within regions is considered. The climate change scenario used indicated increased yields of both crop types in a future climate. Further steps could include a weighting of the wheat and timothy production across soils according to economic analyses.
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Bartley, D. (2014). Do modellers dream of electric sheep? – Practical to mathematical and back again. FACCE MACSUR Mid-term Scientific Conference, 3(S) Sassari, Italy.
Abstract: Disease agents, whether viral, bacterial or parasitic, infecting grazing domestic animals represent a significant threat to livestock health and welfare and to food security, globally. In addition, inefficiency in production due to sub-clinical disease adds significantly to a farm’s environmental footprint. Projected climatic changes over the short-medium term have implications for livestock pests and pathogens, both directly and indirectly, and will result in changing disease patterns e.g. incidence, seasonality and geographic spread. An area where interdisciplinary collaboration is mutually beneficial, and essential in order to gain a better understanding of the interactions between climatic change, pathogen dissemination and livestock productivity is between ‘fundamental’ or ‘practical’ livestock researchers and modellers. To facilitate this collaboration, there needs to be a dialogue between both parties on the data depth, quality and format required to populate different models to ensure relevant and appropriate outputs. An example of where this type of collaboration has been used is work using an Intergovernmental Panel on Climate Change (IPCC)-compliant model (CPLANv2) to calculate greenhouse gases (GHG) associated with fattening lambs over five consecutive grazing seasons. The results demonstrated that effective control of sub-clinical/clinical parasitic gastroenteritis resulted in a ~10% reduction in GHG emissions/kg live weight gain (Kenyon et al., 2013).
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Kondracka, K., Nosalewicz, A., & Lipiec, J. (2014). Effect of drought and heat stresses on transpiration and photosynthesis of wheat. FACCE MACSUR Mid-term Scientific Conference, 3(S) Sassari, Italy.
Abstract: Global warming and frequent extreme weather conditions affect crop yields worldwide. Drought and high temperatures are among stresses that often act simultaneously. Therefore the aim of the studies was to analyze effect of combined drought and heat stresses on growth and function of spring wheat. The experiment was conducted in a growth chamber conditions. Spring wheat cv Łagwa was planted in soil columns of 10cm in diameter and 45cm high filled with Orthic Luvisol developed from loess and grown up to the end of flowering. The treatments were: (C) control with optimum growth soil water potential 160 hPa (pF 2.2), 250 µmol m-2s-1 PAR, 22/18 °C day / night temperatures and 60% air relative humidity throughout growing period; (D) drought stress with soil water potential 250 kPa (pF 3.4) at flowering; (HT) high temperature stress with air temperature 34/24°C and optimum soil water potential ; (DHT) drought (as above) and high temperature (34/24°C day / night) stresses at flowering. During the experiment photosynthesis rate, transpiration and stomatal conductance were measured using the gas exchange system GFS-3000 and DualPAM 100 (Walz, Germany). Drought stress reduced photosynthesis rate by 11%, high temperature by 19% and both stresses by 79% as compared to control (100%). However, drought stress decreased transpiration rate similarly as combined drought and high temperature stresses (by 60-63%). Transpiration rate under high temperature stress compared to control slightly increased.
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Özkan, Ṣ., Bonesmo, H., Østerås, O., & Harstad, O. M. (2014). Effect of Increased Somatic Cell Count and Replacement Rate on Greenhouse Gas Emissions in Norwegian Dairy Herds. FACCE MACSUR Mid-term Scientific Conference, 3(S) Sassari, Italy.
Abstract: Dairy sector contributes around 4% of global greenhouse gas (GHG) emissions, of which 2/3 and 1/3 are attributed to milk and meat production, respectively. The main GHGs released from dairy farms are methane, nitrous oxide and carbon dioxide. The increased trend in emissions has stimulated research evaluating alternative mitigation options. Much of the work to date has focused on animal breeding, dietary factors and rumen manipulation. There have been little studies assessing the impact of secondary factors such as animal health on emissions at farm level. Production losses associated with udder health are significant. Somatic cell count (SCC) is an indicator on udder health. In Norway, around 45, 60 and 70% of cows in a dairy herd at first, second and third lactation are expected to have SCC of 50,000 cells/ml and above. Another indirect factor is replacement rate. Increasing the replacement rate due to health disorders, infertility and reduced milk yield is likely to increase the total farm emissions if the milking heifer replacements are kept in the herd. In this study, the impact of elevated SCC (200,000 cells/ml and above) and replacement rate on farm GHG emissions was evaluated. HolosNor, a farm scale model adapting IPCC methodology was used to estimate net farm GHG emissions. Preliminary results indicate an increasing trend in emissions (per kg milk and meat) as the SCC increases. Results suggest that animal health should be considered as an indirect mitigation strategy; however, further studies are required to enable comparisons of different farming systems.
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