Christian Bugge Henriksen

Minimizing driving times and greenhouse gas emissions in timber transport with a near-exact solution approach

Abstract Efficient transport of timber for supplying industrial conversion and biomass power plants is a crucial factor for competitiveness in the forest industry. Throughout the recent years minimizing driving times has been the main focus of optimizations in this field. In addition to this aim the objective of reducing environmental impacts, represented by carbon dioxide equivalent (CO2 e) emissions, is discussed. The underlying problem is formulated as a multi-depot vehicle routing problem with pickup and delivery and time windows (MDVRPPDTW) and a new iterative solution method is proposed. For the numerical studies, real-life data are used to generate test instances of different scales concerning the supply chain of biomass power plants. Small ones are taken to validate the optimality of the new approach. Medium and large test instances are solved with respect to minimizing driving times and fuel consumptions separately. This study shows that the selection of the objective of minimizing fuel consumption leads to a significant reduction of CO2 e emissions compared to a minimization of driving times.

Exploiting Soil-Management Strategies for Climate Mitigation in the European Union: Maximizing "Win-Win" Solutions across Policy Regimes

The Intergovernmental Panel on Climate Change (IPCC) has identified a number of soil-management strategies that can be implemented to reduce GHG emissions. However, before deciding which of these strategies are most appropriate in any given situation, it is important to investigate how these strategies affect other aspects of sustainable development. For instance, some attempts to sequester carbon in the landscape could alter the soils capacity to filter water. Alternatively, other strategies could unintentionally increase net energy consumption through greater fertilizer use. Focusing specifically on opportunities to implement soil-management strategies in the European Union (EU), we discuss the synergies and trade-offs of those strategies with respect to water resources management and energy security. The focus of the analysis is two-fold: first, we analyze the net benefit of strategies such as crop management, nutrient management, tillage and residue management, water management, and bioenergy vis-a-vis their implications for water resources and energy security; second, we undertake an assessment of the EUs relevant policy frameworks to assess whether the potential synergies from various soil-management strategies are being encouraged or, conversely, where perverse outcomes or trade-offs are likely. Our findings suggest there is much scope to encourage soil-management strategies in Europe that would mitigate greenhouse gas emissions, but these synergies are currently not fully exploited at the EU policy level. We identify a number of options for better policy integration among the Common Agricultural Policy, the Water Framework Directive, and the Climate Action and Renewable Energy Package.

Sustainable Extensification as an Alternative Model For Reducing GHG Emissions From Agriculture. The Case of an Extensively Managed Organic Farm in Denmark

GHG emissions of an extensively managed Danish organic farm were estimated upstream and on-farm. The results were compared to Danish national levels based on land area and output. Overall, the farm emitted 2.12 t CO2eq ha−1 yr−1. Excluding land use, land use change, and forestry (LULUCF) related emissions, the combined GHG emissions from energy- and agriculture-based activities at the case farm were 47% lower (per unit area) and 12% higher (per unit output), than GHG emissions from Danish agriculture. With current livestock density (0.64 LU ha−1) and crop production area, the case study farm would supply at average 1,466 kcal per inhabitant per day in Denmark, if the farm was scaled up to Danish national level. With a reduction of livestock density to 0.36 LU ha−1 and proportional cropland area expansion for food production (ceteris paribus), the case study farm could supply around 4,940 kcal person−1 day−1, matching Danish national levels (including Danish net food export surplus of 41.5%). Simultaneously, the case study farm would have a better GHG balance per unit area and unit output in food, compared to the rest of Denmark. Hence, the case study farm system could serve as an alternative model for Danish agriculture under a sustainable extensification scenario with lower GHG emissions, while maintaining sufficient output for human consumption.

Long-term effects of conversion to organic farming on ecosystem services - a model simulation case study and on-farm case study in Denmark

ABSTRACT Organic agriculture aims to produce food while establishing an ecological balance to augment ecosystem services (ES) and has been rapidly expanding in the world since the 1980s. Recently, however, in several European countries, including Denmark, organic farmers have converted back to conventional farming. Hence, understanding how agricultural ES are affected by the number of years since conversion to organic farming is imperative for policy makers to guide future agricultural policy. In order to investigate the long-term effects of conversion to organic farming on ES we performed i) a model simulation case study by applying the Daisy model to simulate 14 different conversion scenarios for a Danish farm during a 65 year period with increasing number of years under organic farming, and ii) an on-farm case study in Denmark with one conventional farm, one organic farm under conversion, and three organic farms converted 10, 15 and 58 years ago, respectively. Both the model simulation case study and the on-farm case study showed that non-marketable ES values increased with increasing number of years under organic farming. Trade-offs between marketable and non-marketable ES were not evident, since also marketable ES values generally showed an increasing trend, except when the price difference between organic and conventional products in the model simulation study was the smallest, and when an alfalfa pre-crop in the on-farm case study resulted in a significantly higher level of plant available nitrogen, which boosted the yield and the associated marketable ES of the subsequent winter rye crop. These results indicate a possible benefit of preserving long-term organic farms and could be used to argue for agricultural policy interventions to offset further reduction in the number of organic farms or the land area under organic farming.

Effects of the Kemink Exact Soil Management System on Crop Performance and Soil Penetration Resistance

ABSTRACT The Kemink Exact Soil Management System is an alternative soil tillage system developed in Germany between 1970 and 1980. It is based on subsoiling, ridges and controlled traffic. All tillage operations are performed with the special Kemink implements. The soil management system rests on an alternative perception of tillage and soil fertility, which is controversial within both conventional and organic farming. The system has not previously been subjected to experimental comparisons with conventional tillage systems. In this study, the Kemink System and a modified version including ploughing after grass/clover mixtures were compared with a conventional tillage system based on ploughing. A factorial field experiment was conducted in 1998–2000 including tillage systems, crop rotations (barley-grass/cloversugarbeet vs. barley-potato-sugarbeet) and fertilization. The experiment showed that it was often difficult to establish a proper seedbed with the Kemink implements which resulted in reduced crop emergence. Furthermore weed pressure increased during the experiment due to insufficient weed control. Subsoiling only had a loosening effect on the soil in one crop rotation where soil penetration resistance was reduced. Despite a looser soil, there was no general impact on crop yield. There was, however, a positive crop yield development over time showing that the yield in the Kemink System changed from being relatively lower in 1998 and 1999 to the same level as in the traditional tillage system in 2000. In non-manured plots there was a tendency to higher yields in the Kemink System in 2000 and this difference was significant for sugarbeet. There was no significant difference in terms of crop yield between the Kemink System and the modified version which included ploughing. Experimental approaches are discussed and it is assumed that experimental methodology, e.g. plot size and traffic pattern, may influence the performance of tillage systems and thereby conclusion. If farmer skills and knowledge are important to the achievable results it can be argued whether the farmer should be considered to be a part of the tillage system.