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Mittenzwei, K. (2015). The importance of climate and policy uncertainty in Norwegian agriculture (Vol. 5).
Abstract: The paper addresses future climate and policy uncertainty for agricultural production and food security in Norway. The two crop simulation models, CSM-CERES-Wheat and, the LINGRA model, were used to determine the impact of climate change on grain yield of spring wheat, and harvest security and biomass yield of timothy, an important forage grass in Northern Europe, respectively. Harvestable yield distributions from the crop models were fed into a stochastic version of the economic sector model Jordmod. Distributions of the rates of agricultural subsidies rates were assessed based on past policy changes and prospective reforms. The model was used to assess the effects of both climate and policy uncertainty on agricultural production, land use, and national food security. Jordmod is comprised of a supply module in which stochastic profits for more than 300 regional farms are maximized and a deterministic market module which maximizes social welfare in the agricultural sector. Socio-economic scenarios were developed around the level of ambition of Norwegian agricultural policy makers. The model results were contrasted with the deterministic results based on average yield and payment rates. The innovation of this paper lays in assessing the combined effects of future climate and policy uncertainty for the agricultural sector in Norway. It also highlights the potential errors made by neglecting these types of uncertainty in economic modelling. No Label
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Abdelrahman, H., Cocozza, C., Olk, D. C., Ventrella, D., & Miano, T. (2017). Carbohydrates and Amino Compounds as Short-Term Indicators of Soil Management: Soil. Clean Soil Air Water, 45(1), 757.
Abstract: The objective of this work was to evaluate the suitability of carbohydrates and amino compounds in soil and soil organic matter (SOM) fractions to depict the management-induced changes in soil over short-term course. Soil samples were collected from two experimental fields managed according to organic farming regulations and a sequential fractionation procedure was applied to separate the light fraction (LF), particulate organic matter (POM), and mobile humic acid (MHA). Contents of carbohydrates and amino compounds were determined in soil and correspondent SOM fractions. Over a 2-year course, carbohydrate contents decreased in the LF fraction while it increased noticeably in the POM and slightly in the MHA fractions leading into questioning whether decomposing materials get incorporated into older fractions. Amino N content constituted up to 30% of total soil N, with a major contribution of the humic fraction (MHA). Although the LF, POM, and MHA fractions showed the greatest amino N content after the compost-legumes combinations, the carbohydrate and amino N contents in the POM and MHA fractions of the unamended soil increased as large as the corresponding fertilized plots, underlining that conservative soil management results in accumulation of labile forms of soil C and N that consequently might build up soil fertility. The changes after different treatments suggest the suitability of carbohydrates and amino compounds as short-term indicators for soil management.
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Rusu, T. (2014). Energy efficiency and soil conservation in conventional, minimum tillage and no-tillage. International Soil and Water Conservation Research, 2(4), 42–49.
Abstract: The objective of this research was to determine the capacity of a soil tillage system in soil conservation, in productivity and in energy efficiency. The minimum tillage and no-tillage systems represent good alternatives to the conventional (plough) system of soil tillage, due to their conservation effects on soil and to the good production of crops (Maize, 96%-98% of conventional tillage for minimum tillage, and 99.8% of conventional tillage for no till; Soybeans, 103%-112% of conventional tillage for minimum tillage and 117% of conventional tillage for no till; Wheat, 93%-97% of conventional tillage for minimum tillage and 117% of conventional tillage for no till. The choice of the right soil tillage system for crops in rotation help reduce energy consumption, thus for maize: 97%-98% energy consumption of conventional tillage when using minimum tillage and 91% when using no-tillage; for soybeans: 98% energy consumption of conventional tillage when using minimum tillage and 93 when using no-tillage; for wheat: 97%-98% energy consumption of conventional tillage when using minimum tillage and 92% when using no-tillage. Energy efficiency is in relation to reductions in energy use, but also might include the efficiency and impact of the tillage system on the cultivated plant. For all crops in rotation, energy efficiency (energy produced from 1 MJ consumed) was the best in no-tillage — 10.44 MJ ha− 1 for maize, 6.49 MJ ha− 1 for soybean, and 5.66 MJ ha− 1 for wheat. An analysis of energy-efficiency in agricultural systems includes the energy consumed-energy produced-energy yield comparisons, but must be supplemented by soil energy efficiency, based on the conservative effect of the agricultural system. Only then will the agricultural system be sustainable, durable in agronomic, economic and ecological terms. The implementation of minimum and no-tillage soil systems has increased the organic matter content from 2% to 7.6% and water stable aggregate content from 5.6% to 9.6%, at 0–30 cm depth, as compared to the conventional system. Accumulated water supply was higher (with 12.4%-15%) for all minimum and no-tillage systems and increased bulk density values by 0.01%-0.03% (no significant difference) While the soil fertility and the wet aggregate stability have initially been low, the effect of conservation practices on the soil characteristics led to a positive impact on the water permeability in the soil. Availability of soil moisture during the crop growth period led to a better plant watering condition. Subsequent release of conserved soil water regulated the plant water condition and soil structure.
Keywords: No-tillage; Minimum tillage; Yield; Energy efficiency; Soil conservation
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Sieber, S. (2015). The Tanzanian case study in MACSUR II (Vol. 5).
Abstract: The objective of the Tanzanian case study region is to provide MACSUR II a platform to concentrate climate research to a focal region in Morogoro and Dodoma in Tanzania. Hence, synergies among a number of other research projects will be used, which all focus on food security related to climate change.Within the case study region the projects aim at improving the food situation for the most-vulnerable rural poor population in Tanzania. They are designed to identify successful food securing upgrading strategies and innovations along local and regional food value chains, test and adjust them to site-specific, sustainable settings and tailor these concepts to be disseminated for national outreach. After the project lifetime, the results can be implemented at different levels of policy, extension and research.The basic concept applies the following steps in an iterative and partly recurrent procedure: (1) A stakeholder involvement process will be set up from the beginning as an integral part of most analytical steps; (2) case study sites within the focal regions Morogoro and Dodoma will be selected, set up and typologies of food value chains developed; (3) success stories of secure food production and/or good practice along the food value chains will be screened and inventoried; (4) an integrated in-depth analyses of food value chain components, their costs, benefits and impacts will be carried out; (5) a few of the most promising good practices with regard to positive impacts and implementation will be participatively discussed and identified for subsequent in-depth testing; (6) an in-depth participative field testing and/or analysis of selected, most promising technologies will be conducted for all food value chain components and requirements for implementation identified; (7) transferability and implementation capability will be assessed for different scenarios and for future condition simulations (model analysis); (8) a meta-model analysis including risk analysis and final proofing will identify hot spots of most sensitive, fragile regions and the potentials for alleviating food insecurity. Hence, the research concept`s main focuses on local and regional food security related to climate change, but the research design implies a national outreach for Tanzania as a whole.The research activities will be embedded into local and regional strategies to assess potential impacts and trade-offs and to be able to up-scale lessons learnt in a generic manner to regions with specific bio-physical, socio-cultural and economic conditions.Spatial Design: Conducting a literature research on relevant characteristic a considering the spatial design:two focal regions in Tanzania (Morogoro, Dodoma),each region with two case study sites (CSS) consisting of at least one local marketplace and surrounding 2-3 villages,the two CSS among the target regions are selected to differ in factors such as market and capital access for investments, remoteness, population density, land availability, soil types, infrastructure, facilities, and others,create sufficiently diverse environmental and socio-economic conditions for investigating food securing technologies along FVC and allowing for testing the transfer of results to other Tanzanian regions.Main selection criteria for regions: two climates types:semi-arid Dodoma (350-500mm),semi-humid Morogoro region (600-800mm)clear distinction between the regions.other criteria within the regions:rather similar climate (must) +-80mm,weak and good market access (must) (=market and capital access for investments),rainfed crop–livestock systems oriented, not too strongly paddy rice oriented (< 20% rice) (must),village size: approx. 800-1500 households (must)Stunting cases, logistics and infrastructure, different wards, land availability, facilities, capital, soil types, and population density etc. No Label
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Eitzinger, J., Thaler, S., Schmid, E., Strauss, F., Ferrise, R., Moriondo, M., et al. (2013). Sensitivities of crop models to extreme weather conditions during flowering period demonstrated for maize and winter wheat in Austria. J. Agric. Sci., 151(6), 813–835.
Abstract: The objective of the present study was to compare the performance of seven different, widely applied crop models in predicting heat and drought stress effects. The study was part of a recent suite of model inter-comparisons initiated at European level and constitutes a component that has been lacking in the analysis of sources of uncertainties in crop models used to study the impacts of climate change. There was a specific focus on the sensitivity of models for winter wheat and maize to extreme weather conditions (heat and drought) during the short but critical period of 2 weeks after the start of flowering. Two locations in Austria, representing different agro-climatic zones and soil conditions, were included in the simulations over 2 years, 2003 and 2004, exhibiting contrasting weather conditions. In addition, soil management was modified at both sites by following either ploughing or minimum tillage. Since no comprehensive field experimental data sets were available, a relative comparison of simulated grain yields and soil moisture contents under defined weather scenarios with modified temperatures and precipitation was performed for a 2-week period after flowering. The results may help to reduce the uncertainty of simulated crop yields to extreme weather conditions through better understanding of the models’ behaviour. Although the crop models considered (DSSAT, EPIC, WOFOST, AQUACROP, FASSET, HERMES and CROPSYST) mostly showed similar trends in simulated grain yields for the different weather scenarios, it was obvious that heat and drought stress caused by changes in temperature and/or precipitation for a short period of 2 weeks resulted in different grain yields simulated by different models. The present study also revealed that the models responded differently to changes in soil tillage practices, which affected soil water storage capacity.
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