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Soybean production and its supply chain are highly dependent on inputs such as land, fertilizer, fuel, machines, pesticides and electricity. The expansion of this crop in Brazil in recent decades has generated concerns about its environmental impacts. To assess these impacts, two representative chains supplying soybeans to Europe were identified: Center West (CW) and Southern (SO) Brazil. Each supply chain was analyzed using Life Cycle Assessment methodology. We considered different levels of use of chemical and organic fertilizers, pesticides and machinery, different distances for transportation of inputs and different yield levels. Because transportation contributed strongly to environmental impacts, a detailed study was performed to identify the routes used to transport soybeans to seaports. Additionally, we considered different levels of land occupation and land transformation to represent the impact of deforestation in the CW region. Environmental impacts were calculated for 1000 kg of soybean up to and including the delivery to Europe at the seaport in Rotterdam, at 13% humidity. Overall results showed that the impacts are greater for CW than for SO for all impact categories studied, including acidification (7.7 and 5.3 kg SO2 eq., respectively), climate change (959 and 510 kg CO2 eq.), cumulative energy demand (12,634 and 6,999 MJ) and terrestrial ecotoxicity (4.9 and 3.1 kg 1,4-DCB eq.), except eutrophication and land occupation. The same trend was observed for the crop-production stage. Efforts to reduce chemical fertilizers and diesel consumption can reduce CO2 emissions. Although deforestation for crop production has decreased in recent years, the contribution of deforestation to climate change and cumulative energy demand remains significant. In the CW scenario deforestation contributed 29% to climate change and 20% to cumulative energy demand. Results also showed that although there are different transportation options in Brazil, the current predominance of road transport causes severe environmental impacts. In CW, road transport contributed 19% to climate change and 24% to cumulative energy demand, while in SO it contributed 12% and 15% to these impacts, respectively. Improvements in the logistics of transportation, giving priority to rail and river transports over road transport, can contribute significantly to reducing greenhouse gas emissions and decreasing energy use. Future studies involving Brazilian soybeans should take into account the region of origin as different levels of environmental impact are predicted. [Copyright &y& Elsevier]

Abstract: This study aimed to quantify major environmental impacts associated with the production of hemp yarn using Life Cycle Analysis (LCA). A reference scenario of traditional hemp warm water retting was compared to: (1) bio-retting, i.e. hemp green scutching followed by water retting, (2) babyhemp, based on stand retting of pre-mature hemp, (3) dew retting of flax. Overall, neither of the alternative scenarios was unambiguously better than the reference. The impacts of the hemp reference scenario and the flax scenario were similar, except for pesticide use (higher for flax) and water use during processing (higher for hemp). Bio-retting had higher impacts than the reference scenario for climate change and energy use, due to higher energy input in fibre processing. Babyhemp had higher impacts than the reference scenario for eutrophication, land occupation and pesticide use. A reduction of the environmental impacts of hemp yarn should give priority to reduction of energy use in the fibre processing and yarn production stages and to reduction of eutrophication in the crop production phase. [Copyright &y& Elsevier]

Pig production systems often depend to a large extent on concentrated feed imported from outside the farm. This study used the Life Cycle Assessment (LCA) method to assess major environmental impacts associated with the production and on-farm delivery of concentrated feed for pigs. Feed composition was based on average data for Bretagne (France) in 1998 and on published data for wheat-based, maize-based and co-product based feeds. As crop and feed production practices in Bretagne are similar to those in most of western Europe, we conclude that the results of this study apply more largely for western Europe. Depending on feed composition and fertilisation practise for crop-based feed ingredients, the production and delivery of one kg of feed for finishing pigs will produce a eutrophication potential between 3.8 and 9.3 g PO4-equivalents, a global warming potential between 472 and 792 g CO2-equivalents, an acidification potential between 3.0 and 6.3 g SO2-equivalents, a terrestrial ecotoxicity potential between 0.4 and 8.7 g 1,4-dichlorobenzene-equivalents, an energy use between 3.3 and 6.1 MJ, and land use between 1.44 and 2.07 m2 year. These impacts are mainly due to the production of crop-based ingredients. The contribution of transport processes was substantial for climate change, acidification and energy use. A feed containing mainly co-products had higher energy use and lower terrestrial ecotoxicity than feeds consisting mainly of non-processed crop-based ingredients. Hypotheses with respect to the fertilisation practices for the feed''s main ingredients have a major effect on its impact values. The effect of uncertainty concerning the emissions of N2O, NH3, and NO3 was very large for climate change, and large for acidification and eutrophication. The environmental burdens associated with the production and delivery of pig feed can be decreased by: optimising the fertilisation of its crop based ingredients, using more locally produced feed ingredients, reducing concentrations of Cu and Zn in the feed, and using wheat-based rather than maize-based feeds. [Copyright &y& Elsevier]

Current intensive pig production is often associated with environmental burdens. However, very few studies deal with the environmental performance of both current and alternative systems of pig production. The objectives of this study were to evaluate the environmental impacts of three contrasting pig production systems using the life cycle assessment method and to identify hot spots for each system. The scenarios compared were conventional good agricultural practice (GAP) according to French production rules, a French quality label scenario called red label (RL) and a French organic scenario called organic agriculture (OA). For each of the three scenarios a “favourable” and an “unfavourable” variant was defined; these variants were used as indicators of uncertainty with respect to key parameters for technical performance and emissions of pollutants. The environmental categories assessed were: eutrophication, climate change, acidification, terrestrial toxicity, energy use, land use and pesticide use. Two functional units (FU) were used to express impacts: 1 kg of pig produced and 1 ha of land surface used. The scenarios were examined with particular emphasis on their contribution to eutrophication and acidification. Given this perspective, the RL scenario can be an interesting alternative to GAP on the condition that its emission of greenhouse gases can be reduced. The results for OA were very dependent on the choice of the FU. Per kg of pig, eutrophication and acidification were similar for OA and GAP, while OA had less eutrophication and acidification than GAP when expressed per ha. For the three scenarios, environmental hot spots and important margins of improvement were identified. Finally, the uncertainty analysis indicated that efforts should be made to produce more reliable estimations of emission factors for NO3, NH3 and N2O in the field. [Copyright &y& Elsevier]

The current industrial pig production model is in crisis, due to its association with environmental pollution, doubtful product quality and lack of animal well-being. In Bretagne (France), a region of intensive pig production, a survey of seven stakeholder groups concerned with pig production was conducted, as part of a research programme dedicated to the assessment of the environmental impact of different modes of pig production. A very large majority of pig producers (93%) and their suppliers (100%) considers pig farms as an asset for the region, whereas a majority of scientists (58%), activists (78%) and consumers (54%) sees it as a handicap. Differences among stakeholder groups are minor with respect to the perceived importance of environmental and social issues. Stakeholders agree on the relative level of responsibility of pig farms with respect to specific problems. For all groups unpleasant odours and water quality come first with respect to responsibility, for most groups soil quality comes second, followed by product safety and air quality. For a future improved mode of pig production, 76% of pig producers and their suppliers prefer to adapt the current model, for all other groups the majority prefers an alternative model. While pig producers and their suppliers prefer a slurry-based housing system, all other groups prefer a straw-based system. Pig producers see the slurry-based system as technically superior and associate the straw-based system with poor working conditions, whereas consumers associate the slurry-based system in the first place with poor water quality and associate the straw-based system with less pollution. These results will be of use in the research programme on the environmental impact of modes of pig production, as they indicate the environmental impacts to be considered and their relative importance. The results will also help in deciding which options should be assessed. It is concluded that the poor image of the current pig production model and its production practices with consumers does not seem compatible with a sustainable demand for pork products. [Copyright &y& Elsevier]

An increasing variety of evaluation methods is being proposed to address the question of the environmental impacts of agriculture. This paper compares and analyses 12 indicator-based approaches to assessing environmental impact at the farm level, in order to propose a set of guidelines for the evaluation or development of such methods. These methods take into account a number of environmental objectives (e.g. soil erosion, water quality). A set of indicators is used to quantify the degree to which these objectives are attained. A total of 26 objectives were taken into account by one or several of the methods. A great diversity in breadth of analysis exists: the number of objectives considered per method varies from 2 to 13. Indicator-based methods for environmental evaluation at the farm level should take into account a range of objectives covering both local and global effects. Indicators based on the environmental effects of farmer practices are preferable to indicators based on farmer practices as the link with the objective is direct and the choice of means is left to the farmer. Indicators based on farmer practices cost less in data collection but do not allow an actual evaluation of environmental impact. Indicators allowing expression of impacts both per unit surface and per unit product are preferable. Indicators producing output in the form of values are preferred to indicators producing scores. If possible, science-based threshold values should be defined for indicators. The method should be validated with respect to (a) the appropriateness of its set of objectives relative to its purpose and (b) its indicators. [Copyright &y& Elsevier]

Abstract: The environmental consequences of replacing fish meal and fish oil with plant-based sources in salmonid feeds were investigated using Life Cycle Assessment (LCA). Two scenarios of Atlantic salmon (Salmo salar) and rainbow trout (Oncorhynchus mykiss) farming were compared. The first scenario used a Standard Diet (STD) with high levels of fish meal and fish oil, and the second a Low Marine-Fishery-Capture Diet (LFD) in which fish meal and fish oil were replaced by plant protein and oil sources. Environmental impacts assessed were: acidification, eutrophication, climate change, terrestrial ecotoxicity, net primary production use (biotic resource use), water use, land occupation and total cumulative energy demand. The assessment confirmed the substantial contribution of feed to the environmental burdens of fish production and the LFD scenario led to a significant decrease in biotic resource use compared to the STD scenario with the same total energy demand. Environmental impacts of feeds depended highly on the geographic origins of feed ingredients from fishery (e.g., fish oil from Norway or Peru) and from terrestrial agricultural crop species (e.g., palm oil or rapeseed oil). This study demonstrated the importance of a multicriteria method to give stakeholders the most accurate information on the potential consequences of replacing fishery products with plant-based sources in aquafeeds. [Copyright &y& Elsevier]