• Energy Research

This paper summarizes the main findings of the GLAMUR project which starts with an apparently simple question: is “local” more sustainable than “global”? Sustainability assessment is framed within a post-normal science perspective, advocating the integration of public deliberation and scientific research. The assessment spans 39 local, intermediate and global supply chain case studies across different commodities and countries. Assessment criteria cover environmental, economic, social, health and ethical sustainability dimensions. A closer view of the food system demonstrates a highly dynamic local–global continuum where actors, while adapting to a changing environment, establish multiple relations and animate several chain configurations. The evidence suggests caution when comparing “local” and “global” chains, especially when using the outcomes of the comparison in decision-making. Supply chains are analytical constructs that necessarily—and arbitrarily—are confined by system boundaries, isolating a set of elements from an interconnected whole. Even consolidated approaches, such as Life Cycle Assessment (LCA), assess only a part of sustainability attributes, and the interpretation may be controversial. Many sustainability attributes are not yet measurable and “hard” methodologies need to be complemented by “soft” methodologies which are at least able to identify critical issues and trade-offs. Aware of these limitations, our research shows that comparing local and global chains, with the necessary caution, can help overcome a priori positions that so far have characterized the debate between “localists” and “globalists”. At firm level, comparison between “local” and “global” chains could be useful to identify best practices, benchmarks, critical points, and errors to avoid. As sustainability is not a status to achieve, but a never-ending process, comparison and deliberation can be the basis of a “reflexive governance” of food chains.

The sustainability of food value chains is an increasing concern for consumers, food companies and policy-makers. Global food chains are often perceived to be less sustainable than local food chains. Yet, thorough food chain analyses and comparisons of different food chains across sustainability dimensions are rare. In this article we analyze the local Belgian and global Peruvian asparagus value chains and explore their sustainability performance. A range of indicators linked to environmental, economic and social impacts is calculated to analyze the contribution of the supply chains to economic development, resource use, labor relations, distribution of added value and governance issues. Our findings suggest that none of the two supply chains performs invariably better and that there are trade-offs among and between sustainability dimensions. Whereas the global chain uses water and other inputs more intensively and generates more employment per unit of land and higher yields, the local chain generates more revenue per unit of land.

AbstractDue to higher oil prices, abundance of labor and suitable land and its stable political climate, Tanzania attracted many investments in Jatropha. Although several studies on Jatropha's economic potential are available, its true economics are still uncertain. This paper aims to add to the growing body of knowledge on the socio‐economic performance of the Jatropha system by (i) studying the economic potential (net present value – NPV) of the current most prevailing Jatropha system for Tanzanian farmers and its regional differences, by (ii) making a greenhouse gas (GHG) balance and its economic value of the Jatropha activities on regional level, and by (iii) calculating break‐even thresholds for yield and seed price. Therefore, regional yield modeling, regional life‐cycle assessment, and NPV calculations based on Monte Carlo simulations, each with its set of assumptions, are combined. This study shows positive economic potential of Jatropha cultivation in most of the Tanzanian regions. However, the results also show that 13 of 20 Tanzanian regions will not attain a net positive GHG balance within 10 years. This indicates that the environmental impacts might be more restrictive for Jatropha's sustainability potential in Tanzania than the socio‐economic potential. These results are based on the combination of three models, which consists of strong interdisciplinary modeling work. However, this modeling also contains simplifications (e.g., no opportunity cost for ‘marginal’ land) and uncertainties (e.g., using globally modeled potential yield estimations), which have to be considered in the interpretation of the results.

International agri-food trade has expanded rapidly during the past decades and changed considerably in structure with important implications, especially for developing economies. One of the main environmental concerns regarding international trade is the exploitation and redistribution of water resources. In this paper, we use the virtual water approach for analyzing the relationship between global agri-food trade, its structure and virtual water flows in the period of 1986–2011. Specifically, for five regions and the world, we calculate growth rates of interregional trade values and virtual water volumes, the contribution of different product groups to trade and the economic water efficiency of imports and exports. Our findings show that, over time, trade values have generally increased more rapidly than virtual water volumes. In Africa and Southern America, virtual water outflows have roughly quadrupled since 1986. In all regions, staples and industrial products account for the largest share in virtual water trade. The recent shift towards high-value exports is beneficial for low-income countries from a regional economic water efficiency perspective due to high trade values and low associated virtual water volumes. Economic water efficiency of trade has increased in all regions since 2000 and the return to virtual water outflows is especially high in Europe.

This study compares a life cycle assessment (LCA) of pork production in the Western Cape with pork production in Flanders. The objectives of this study were to map and quantify the environmental impacts of producing pork in the Western Cape and exporting it to Antwerp in Flanders with the environmental impacts of producing pork in Flanders and delivering it to the same location. The impact categories included are (i) global warming potential (GWP), (ii) eutrophication potential, (iii) acidification potential, and (iv) energy use. By pointing out weak points in the different environmental impact categories, suggestions are made to lower the environmental burdens of pork production. Four main activities of the pork production chain were covered by the LCA, namely: (i) the feed provision activity, which includes the production of raw materials and feed, (ii) the pig farming activity, (iii) the slaughter house activity and (iv) the slurry (treatment) activity. An additional (v) pork shipping activity was added in the case of the Western Cape pork chain. A cradle-to-gate life cycle assessment was carried out, with a functional unit (FU) of one kg of Western Cape or Flemish pork (carcass weight) delivered to the distribution centre in Antwerp. Flemish GWP, eutrophication potential, acidification potential and energy use are 56%, 65%, 62% and 59% respectively of the Western Cape equivalents. The exporting of pork accounts for less than 8% of environmental impacts in all impact categories. Potential exists in the Western Cape to compete on an environmental par when impacts are measured in terms of a per-area unit. It is therefore recommended that for future comparative South African-European LCA studies of pork or other intensive livestock or poultry production chains, an FU of one kg meat as well as an area unit be used when measuring total eutrophication and acidification impacts

In a greenhouse experiment we applied three levels of drought stress and monitored growth variables and biomass production of Jatropha curcas seedlings propagated from three seed accessions. We determined biomass allocation, allometric relationships and plant traits. Well-watered J. curcas seedlings grew 0.81 � 0.15 cm day � 1 in length and produced 1.49 � 0.31 g dry biomass day � 1 . Under medium stress (40% plant available water) the plants