INTEGRATING SUSTAINABILITY IN AGRICULTURE - TRADE-OFFS AND ECONOMIC CONSEQUENCES DEMONSTRATED WITH A FARM MODEL IN BAVARIA

Within the German "Research Alliance on Agroecosystems Munich" (Forschungsverbund Agrarökosysteme München, FAM) optimal land use strategies are investigated since 1990 in terms of minimization of environmental impacts and maximization of profit from agricultural lands (Auerswald et al. 2000). For this purpose a conventional agricultural land use system was converted into two more sustainable forms of land use. One part of the farm was converted into an integrated land use system with reduced tillage, direct seeding methods and catch crops to minimize nutrient losses and to prevent soil erosion hazards. The other part of the farm was converted into a biological land use system with the omission of mineral fertilizers and pesticides and the enrichment of crop rotation. In order to evaluate changes in the state of the agroecosystem a goal and indicator system was elaborated which was aimed to represent important issues of sustainable agriculture. With the help of the goal and indicator system the impact of land use on issues of sustainability can be assessed. The indicators are furthermore integrated into a farm model to assess the implications of the realization of environmental issues in agriculture. For this purpose the model system MODAM (Zander & Kächele 1999) was used to compare different land use options at the farm level. The model system simulates agricultural land use, calculates the economic returns and runs farm optimizations with a linear programming tool. The integration of agro-environmental indicators in the model framework enables a multiple goal optimization and the calculation of trade-offs. For this study soil erosion was assessed with the algorithms of a site-specifically adapted version of the USLE (ABAG, Schwertmann et al. 1987). Optimization runs show, that e.g. soil conservation measures may not only improve soil conservation, but also the economic situation. A slight improvement of soil conservation results in marginal opportunity costs for the farm. With the realization of a higher level of soil protection opportunity costs rise exponentially. The calculated opportunity costs can give valuable hints on bottlenecks of the realization of sustainable agriculture and help to identify reasonable incentives for a better agriculture. Furthermore conflicts between divagating goals can be identified to find optimal pathways of a sustainable development of agriculture.Environmental Economics and Policy, Farm Management,

Whole Farm Modeling of the Effect of Risk on Optimal Tillage and Nitrogen Fertilizer Intensity

nitrogen, tillage, risk, risk aversion, Crop Production/Industries, Farm Management, Production Economics, Risk and Uncertainty,

Cost Efficient Tillage and Rotation Options for Mitigating GHG Emissions from Agriculture in Eastern Canada

The economic efficiency of cropping options to mitigate GHG emissions with agriculture in Eastern Canada was analyzed. Data on yield response to tillage (moldboard plow and chisel plow) and six corn based rotations were obtained from a 20-year field experiment in Ontario. Budgets were constructed for each cropping system while GHG emissions were measured for soil carbon and were estimated for nitrous oxide according to IPCC methodology. Complex crop rotations with legumes, such as corn-corn-soybeans-wheat with red clover underseeded, have higher net returns and substantially (more than 1 Mg ha1 year1) lower GHG emissions than continuous corn. Reduced tillage reduces GHG emissions due to lower input use but no sequestration effect could be found in the soil from tillage. Rotation had a much bigger effect on the mitigation potential of GHG emissions than tillage. However, opportunity costs of more than $200 per Mg CO2 eq ha1 year1 indicate the limits to increase the mitigation potential beyond the level of the economic best cropping system.Environmental Economics and Policy,

Economic analysis of site-specific wheat management with respect to grain quality and separation of the different quality fractions

The paper analyzes site-specific and uniform management options for wheat production with respect to grain quality. Besides site-specific fertilization the economic potential of segregation of different grain qualities is the subject of this paper. Yield and quality response to fertilizer were taken from field experiments in Germany to calculate site-specific response functions. The economic optima were calculated for uniform management (UM), complete separate management of the subfields (SM), site-specific fertilization (SSF) and grain segregation (GS) for different price structures according to different grain qualities. The results show that over all price structures, highest economic potential was found with SM or SSF compared to UM. However, these management practices require the possibility to separately manage subfields (SM) or specific fertilization equipment and fertilizer algorithms (SSM). GS did not have a higher economic potential than UM. However, if required grain qualities are not met for the whole field, GS can substantially reduce profit losses by separating part of the grains and selling them at higher prices. This may save the farmer more than 50 € ha–1. In situations where higher grain qualities could only be obtained at the expense of yield penalties, premiums for higher grain qualities can create incentives for fertilizer rates beyond the yield maximizing rate. GS technologies may even boost this effect.site-specific nitrogen management, wheat quality, grain segregation., Crop Production/Industries,

Effectiveness of Best Management Cropping Systems to Abate Greenhouse Gas Emissions

Best management practices (BMPs) for cropping systems that involve conservation tillage and nutrient management are proposed as potential win-win solutions for both farmers and the environment. While originally targeted as a means for improving soil and water quality, these BMPs may also contribute to the mitigation of greenhouse gases (GHGs). Mitigation efforts have focused primarily on the ability of BMPs to sequester carbon and the subsequent potential revenue source carbon sequestration may represent to farmers. Increasingly, evidence from experimental stations calls into question the potential for C-sequestration with reduced tillage in soils in Eastern Canada. However, there are other ways in which BMPs can reduce GHG emissions: lowering fuel and nitrogen fertilizer consumption and, potentially, lowering emissions of nitrous oxide from the soil. This article examines the profitability and emission reduction potential of best management cropping practices for Ontario.Agricultural and Food Policy, Farm Management,

Greenhouse Gas Mitigation Costs of Reduced Nitrogen Fertilizer

The reduction of nitrogen (N) fertilizer use is a possible greenhouse gas (GHG) mitigation option, whereas cost estimation highly depends on assumptions of the yield response function. This paper analyzes the potential and range of GHG mitigation costs with reduced N fertilizer application based on empirical yield response data for winter rye (Secale cereale L.) and rapeseed (Brassica napus L.) from field experiments from 2013 to 2020 in Brandenburg, Germany. The field experiments included four to five N rates as mineral fertilizer treatments. Three different functional forms (linear-plateau, quadratic, and quadratic-plateau) were estimated to model yield response as a function of N supply. Economic calculations were based on relevant price–cost ratios. The results indicate that the opportunity costs of applying less fertilizer and the resulting GHG mitigation thereof vary in a great range across the years and crops estimated by different yield response functions. The linear-plateau function predominantly results in lower GHG mitigation costs than the quadratic and the quadratic-plateau function. On average, over eight years, a moderate reduction of N fertilizer (up to 20 kg/ha) offers a cost-efficient option for mitigating GHG emissions below EUR 50 per ton of CO2eq, even resulting in net profit gain in some cases

Greenhouse gas emissions and mitigation options for German wine production

In the light of a dire need to reduce greenhouse gas emissions (GHG) from food value chains, this paper analyses GHG emissions from wine production based on primary data from 5 wineries, one wine cellar and 9 grape producers in Germany and explores main emission sources based on their contributions to variance. Considering system boundaries from cradle to gate we found a 90% confidence interval for results between 0.753 and 1.069 kg CO2e per bottle of wine. Main contributors to variance were bottle weight (31%), electricity usage (18%), heat (11%), yield (−9%), and diesel use in vineyards (9%). Looking at production process phases, 19% of emissions resulted from the production of wine grapes, while 81% were attributable to the winery phase, mainly to the packaging materials (57%). Exploring the mitigation potential of a reduction in bottle weight, reuse of glass bottles, increase in packaging volume and renewable energies, we found that the reuse of glass bottles deserves close attention from wine producers, consumers, and policy makers who strive for an effective decarbonization of the wine value chain. The mitigation potential of the reuse of an average bottle exceeds the mitigation potential from a reduction in bottle weight by more than threefold. A combination of the replacement of grid electricity by renewable energies, bottle weight reduction and reuse can curb GHG emissions per bottle of wine by 47%.Peer reviewe

CO2-VERMEIDUNGSKOSTEN DER STROM- UND WÄRMEPRODUKTION AUS BIOGAS

In einer Studie wurden die volkswirtschaftlichen Kosten verschiedener Produktionsverfahren und Szenarien der Strom- und Wärmeproduktion aus Biogas auf der Basis von Mais und Rindergülle untersucht. Gemessen an alternativen Maßnahmen, verursacht die staatliche Förderung der Bioenergieproduktion aus Biogas, durch das Erneuerbare-Energien-Gesetz (EEG), hohe volkswirtschaftliche Kosten. Die CO2-Vermeidungkosten variieren zwischen 289 und 691 €/t CO2äq in den untersuchten Produktionsverfahren und Szenarien. Der Subventionsaufwand beläuft sich auf 310 bis 596 €/t CO2äq.Bioenergie, Biogas, ökonomische Analyse, CO2-Vermeidungskosten, Agribusiness, Agricultural and Food Policy, Agricultural Finance, Demand and Price Analysis, Environmental Economics and Policy, Farm Management, Financial Economics,

Physical Modeling of Process-Machine-Interactions in Micro Machining

Increasing demands for smaller and smarter devices in a variety of applications requires the investigation of process-machine-interactions in micro manufacturing to ensure process results that guarantee part functionality. One approach is the use of simulation-based physical models. In this contribution, methods for the physical modeling of high-precision air bearing and magnetic bearing spindles are presented in addition to a kinematic model of the micro milling process. Both models are superimposed in order to carry out investigations of the slot bottom surface roughness in micro end milling. The results show that process-machine-interactions in micro manufacturing can be modeled by the superposition of a physical model of the machine tool spindle taking cutting forces into consideration and a purely kinematic model of the machining process, providing the necessary tools for a variety of further investigations into process-machine-interactions in micro manufacturing

Integration von Umweltzielen in die Betriebsoptimierung im ökologischen Landbau – Möglichkeiten und Grenzen am Beispiel des Versuchsbetriebes Klostergut Scheyern

Am Beispiel der Reduzierung von Bodenerosion konnte modellhaft gezeigt werden, dass die Integration von Umweltzielen für einen integrierten Betrieb mit geringeren Opportunitätskosten verbunden ist, als dies bei dem ökologisch wirtschaftenden Betrieb der Fall ist. Aufgrund der Notwendigkeit einer vielfältigen Fruchtfolge mit Zwischenfrüchten bzw. Untersaaten im ökologischen Landbau, ist das Erosionsrisiko im ökologisch wirtschaftenden Betrieb bereits ohne Auflagen deutlich niedriger, als die im integrierten Betrieb. Ein integrierter Betrieb ist in der Regel nur durch Zahlung von Prämien zu einer Berücksichtigung von Umweltzielen bereit. Diese Anreize werden dem ökologischen Landbau bereits durch die höheren Produktpreise sowie die Grundförderung gesetzt. Die dargestellten Zusammenhänge helfen aufzuzeigen, wie effizient Umweltziele erreicht werden können