Author(s): Ian Vázquez Rowe y otros
(Español) Purpose: Consequential Life Cycle Assessment (C-LCA) is a “system modelling approach in which activities in a product system are linked so that activities are included in the product system to the extent that they are expected to change as a consequence of a change in demand”. Hence, C-LCA focuses on micro-economic actions linked to macro-economic consequences, by identifying the (marginal) suppliers and technologies prone to be affected by variable scale changes in the demand of a product. Detecting the direct and indirect environmental effects due to changes in the production system is not an easy task. Hence, researchers have combined the consequential perspective with different econometric models. Therefore, the aim of this study is to assess an increase in biocrops cultivation in Luxembourg using three different consequential modelling approaches to understand the benefits, drawbacks and assumptions linked to each approach as applied to the case study selected. Methods: Firstly, a partial equilibrium (PE) model is used to detect changes in land cultivation based on the farmers’ revenue maximisation. Secondly, another PE model is proposed, which considers a different perspective aiming at minimising a total adaptation cost (so-called opportunity cost) to satisfy a given new demand of domestically produced biofuel. Finally, the consequential system delimitation for agricultural LCA approach, as proposed by Schmidt (Int J Life Cycle Assess 13:350–364, 2008), is applied. Results and discussion: The two PE models present complex shifts in crop rotation land use changes (LUCs), linked to the optimisation that is performed, while the remaining approach has limited consequential impact on changes in crop patterns since the expert opinion decision tree constitutes a simplification of the ongoing LUCs. However, environmental consequences in the latter were considerably higher due to intercontinental trade assumptions recommended by the experts that were not accounted for in the economic models. Environmental variations between the different scenarios due to LUCs vary based on the different expert- or computational-based assumptions. Finally, environmental consequences as compared with the current state-of-the-art are lame due to the limited impact of the shock within the global trade market. Conclusions: The use of several consequential modelling approaches within the same study may help widen the interpretation of the advantages or risks of applying a specific change to a production system. In fact, different models may not only be good alternatives in terms of comparability of scenarios and assumptions, but there may also be room for complementing these within a unique framework to reduce uncertainties in an integrated way.
Open linkAuthor(s): Ian Vázquez Rowe y otros
(Español) Goose barnacles constitute an important market product in Spain, where they are considered a top seafood attraction in first-class restaurants. However, their environmental sustainability has not been explored beyond the implementation of co-management schemes to avoid overexploitation. Therefore, the main objective of this article is to understand the environmental implications of goose barnacles in terms of carbon footprint (CF), in the wake of recent studies which have highlighted the importance that fishing systems can have on climate change, as well as to facilitate accountability concerning CF reduction policies for stakeholders and consumers. Results for the six scenarios under analysis showed substantial changes depending on the harvesting area and especially on the means of transport chosen, since this intertidal species can be accessed by land or by sea. The average CF per kg of harvested barnacles ranged from 0.64 kg CO2 equiv. to over 11 kg CO2 equiv., showing substantially higher CF values whenever the resource was accessed by sea. The wide CF gap observed between harvesting carried out on foot or by sea suggests that different management schemes should be implemented for each of the two methods in terms of environmental monitoring, as well as different strategies concerning environmental transparency and reporting.
Open linkAuthor(s): Karin Bartl y otros
(Español) Crop and technology choices in agriculture, which largely define the impact of agricultural production on the environment, should be considered in agricultural development planning. A life cycle assessment of the dominant crops produced in a Peruvian coastal valley was realized, in order to establish regionalized life cycle inventories for Peruvian products and to provide the basis for a regional evaluation of the impacts of eutrophication, acidification, human toxicity, and biodiversity loss due to water use. Five scenarios for the year 2020 characterized by different crop combinations and irrigation systems were considered as development options. The results of the regional assessment showed that a business-as-usual scenario, extrapolating current trends of crop cultivation, would lead to an increase in nitrate leaching with eutrophying effects. On the other hand, scenarios of increased application of drip irrigation and of mandarin area expansion would lead to a decrease in nitrate leaching. In all scenarios the human toxicity potential would decrease slightly, while an increase in irrigation water use would benefit the biodiversity of a nearby groundwater-fed wetland. Comparisons with results from other studies confirmed the importance of regionalized life cycle inventories. The results can be used as decision support for local farmers and authorities.
Open linkAuthor(s): Ramzy Kahhat Abedrabbo y otros
(Español) The management of electronic waste (e-waste) presents new sustainability challenges, prominent among these is informal electronic recycling in the developing world fed by both international and domestic sources. There is a need to mitigate environmental impacts of informal recycling while maintaining social and economic benefits of refurbishment and reuse. The development of appropriate social responses is hindered by critical data gaps, which include lack of data on trade flows of used and scrap electronics, flows invisible to trade statistics of many countries. We address this data gap by proposing and implementing an approach to quantify the exportation of used and scrap equipment from a particular country or region to the rest of the world. The approach is based on material flow analysis and combines collection of primary survey data from residential and business/public sectors with secondary data from available recycling, landfill and computer adoption studies. Exports are estimated through materials balance: exports = generated − reuse − recycling − landfill. The proposed methodology is implemented in a case study of desktop (excluding monitors) and laptop computers in the United States (US) in 2010. Results indicate that 40 million used and scrap computers entered the end-of-life management sector, from which 30% were reused domestically, 6–29% were exported, 17–21% were landfilled in domestic sites and 20–47% were collected for domestic recycling in 2010. The range in results reflects uncertainty arising from inferring end-of-life fate from individual and institutional users. Given sufficient resources to conduct a survey, the proposed materials flow analysis method can be widely applied to other devices and nations.
Open linkAuthor(s): Karin Bartl y otros
(Español) Global water use is dominated by agriculture and has considerable influence on people’s livelihood and ecosystems, especially in semiarid and arid regions. Methods to address the impacts of water withdrawal and consumption on terrestrial and aquatic ecosystems within life cycle assessment are still sparse and very generic. Regionalized characterization factors (CFs) for a groundwater-fed wetland at the arid coast of Peru are developed for groundwater and surface water withdrawal and consumption in order to address the spatial dependency of water use related impacts. Several agricultural scenarios for 2020 were developed in a workshop with local stakeholders and used for calculating total biodiversity impacts. In contrast to assumptions used in top-down approaches (e.g., Pfister et al. Environ. Sci Technol.2009, 43, 4098), irrigation with surface water leads in this specific region to benefits for the groundwater-fed wetland, due to additional groundwater recharge from surplus irrigation water. However, irrigation with groundwater leads to ecological damage to the wetland. The CFs derived from the different scenarios are similar and can thus be used as general CFs for this region, helping local decision-makers to plan future agricultural development, including irrigation technologies, crop choices, and protection of the wetland.
Open linkAuthor(s): Red Peruana Ciclo de Vida y otros
(Español) Purpose: The main purpose of this article is to propose specific discard indexes for their development in fisheries life cycle assessment (LCA). The objective of these is to characterize and standardize discards in worldwide fisheries. Methods: The global discard index (GDI) is intended to be an easily understood index whose use is extendible to any fishery in the world. It is presented as a dynamic index that aims to characterize and standardize discard rates between fisheries by direct comparison with the global discard rates reported periodically by FAO. Furthermore, a simplified approach excluding characterization is presented for scenarios in which the data quality linked to discards is poor. Two additional indicators, survival rate of discards and slipping, are proposed to improve the reporting and quantification of biomass waste by fishing vessels. Results: GDI implementation, together with two other fishery-specific impact categories, showed remarkable differences in the environmental impacts of several fishing fleets when compared with the obtained results for conventional impact categories. Results for the conventional categories were strongly influenced by the energy use in the fishery, while results obtained for fishery-specific categories presented variable trends due to the dependence on a wider range of factors. GDI inclusion favored direct comparison with worldwide average discard rates on a time scale basis, from a wet weight or a net primary productivity perspective, depending on the selected approach. Conclusions: Proposed indicators achieved the important objective of integrating discard data as a fishery-specific impact in fishery LCAs, increasing the benefits of implementing LCA in fisheries assessment. Specific advantages of these indicators include assessing changes in capture and landing composition, evaluating the selectivity of the fishing gears, and monitoring the behavior of fisheries in a normalized context respect to other fisheries. GDI was identified as an adequate methodological improvement for regular use in fisheries LCA. Future developments GDI include its harmonization for inclusion in damage assessment.
Open linkAuthor(s): Ian Vázquez Rowe y otros
(Español) An important percentage of European wine appellations base their production on a broad number of vine-growers that annually sell their grapes to the wineries under the specific Denomination of Origin. Hence, the use of average values for the environmental evaluation of this type of multiple datasets can create large standard deviations that may impede an adequate interpretation of the results. Combined implementation of Life Cycle Assessment (LCA) and Data Envelopment Analysis (DEA), known as LCA + DEA methodology, has proven to be a suitable tool for assessing multiple input/output data in several agri-food systems, such as aquaculture, farming or fisheries. In the current study, a total of 40 vine-growing exploitations belonging to the Rías Baixas appellation (NW Spain) were analyzed following LCA + DEA methodology in order to determine the level of operational efficiency of each producer. Furthermore, potential reductions in the consumption levels of the material inputs were benchmarked, while calculating the environmental gains linked to these reduction targets, thus verifying eco-efficiency criteria. Results led to average reduction levels of up to 30% per material input, which translated into environmental gains that ranged from 28% to 39% depending on the selected impact category. Additionally, a super-efficiency analysis led to identify the best performing units, which were used as a source of reference values for environmental impacts. Finally, potential economic savings of 0.14 € per functional unit (i.e., 1.1 kg of grapes for the production of a common 750 ml bottle of wine) were estimated on the basis of efficient vine-growing practices.
Open linkAuthor(s): Isabel Quispe Trinidad
(Español) The goal of this project was to enhance the use of the life cycle approach within the Latin-American Region. It was focused on capacity building for developing Regional Life Cycle Inventories. The project was developed by researchers belonging to the LCA community in cooperation with UNEP, and Governmental representatives and statistic offices providing the data. More precisely, this project aimed at building home-grown expertise, including capacity for South-South cooperation, environmental leadership, and also at supporting the use of science-based approaches and evidence-based decision-making in mainstreaming environment in government policies in each of the countries participating in the project. The critical review process is still to be done, but it must be accomplished by June of 2011. The project started with the establishment of general rules for harmonization of sound and comprehensive life cycle inventory data and information. These rules were applied to the field of electricity production, transmission and distribution. This productive sector was chosen due to the fact that it is a common and necessary key input to all economic activities. Results: A quality guideline was developed for the project, based on the one used to build the national Brazilian LCI. Four different LCI were built in ecospold format, based on information collected in four different countries, Argentina, Chile, Mexico and Peru, which cover the hydroelectric and thermoelectric generation processes, and the transmission and distribution systems. Lack of LCA acknowledge in the industrial and public sectors, and difficulties to find reliable public data and information, arise as the major problems in most of the participating countries, even though the electric sector is more incline than other sectors in providing the public with more and more information regarding its emissions and compliances. The capacity building process and differences between the countries in terms of structure, technology, environmental regulations, among other factors, made the use of a common and detailed quality guideline very difficult to be applied. Thus, capacity building process on LCA in emerging regions seems better to be conducted on a step-by-step basis, which must consider the development of a simpler approach to build generic prototype models that can undergo later a continuous improving process. Data consistency and harmonization appears to be two of the major issues that must be specifically addressed in a Regional quality guideline.
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