246 research outputs found
Variation in carbon footprint of milk due to management differences between Swedish dairy farms
To identify mitigation options to reduce greenhouse gas (GHG) emissions from milk production (i.e. the carbon footprint (CF) of milk), this study examined the variation in GHG emissions among dairy farms using data from previous CF studies on Swedish milk. Variation between farms in these production data, which were found to have a strong influence on milk CF were obtained from existing databases of e.g. 1051 dairy farms in Sweden in 2005. Monte Carlo analysis was used to analyse the impact of variations in seven important parameters on milk CF concerning milk yield (energy corrected milk (ECM) produced and delivered), feed dry matter intake (DMI), enteric methane emissions, N content in feed DMI, N-fertiliser rate and diesel used on farm. The largest between farm variation among the analysed production data were N-fertiliser rate (kg/ha) and diesel used (l/ha) on farm (coefficient of variation (CV) 31-38%). For the parameters concerning milk yield and feed DMI the CV was approx. 11 and 8%, respectively. The smallest variation in production data was found for N content in feed DMI. According to the Monte Carlo analysis, these variations in production data led to a variation in milk CF of between 0.94 and 1.33 kg CO2 equivalents (CO2e) per kg ECM, with an average value of 1.13 kg/CO2e kg ECM. We consider that this variation of ±17% that was found based on the used farm data would be even greater if all Swedish dairy farms were included, as the sample of farms in this study was not totally unbiased. The variation identified in milk CF indicates that a potential exists to reduce GHG emissions from milk production on both national and farm level through changes in management. As milk yield and feed DMI are two of the most influential parameters for milk CF, feed conversion efficiency (i.e. units ECM produced per unit DMI) can be used as a rough key performance indicator for predicting CF reductions. However, it must be borne in mind that feeds have different CF due to where and how they are produced
The effectiveness of anaerobic digestion in removing estrogens and nonylphenol ethoxylates
This is the post-print version of the final paper published in Journal of Hazardous Materials. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2011 Elsevier B.V.The fate and behaviour of two groups of endocrine disrupting chemicals, steroid estrogens and nonylphenol ethoxylates, have been evaluated during the anaerobic digestion of primary and mixed sewage sludge under mesophilic and thermophilic conditions. Digestion occurred over six retention times, in laboratory scale reactors, treating sludges collected from a sewage treatment works in the United Kingdom. It has been established that sludge concentrations of both groups of compounds demonstrated temporal variations and that concentrations in mixed sludge were influenced by the presence of waste activated sludge as a result of transformations during aerobic treatment. The biodegradation of total steroid estrogens was >50% during primary sludge digestion with lower removals observed for mixed sludge, which reflected bulk organic solids removal efficiencies. The removal of nonylphenol ethoxylates was greater in mixed sludge digestion (>58%) compared with primary sludge digestion and did not reflect bulk organic removal efficiencies. It is apparent that anaerobic digestion reduces the concentrations of these compounds, and would therefore be expected to confer a degree of protection against exposure and transfer of both groups of compounds to the receiving/re-use environment.Thames Water, Yorkshire Water, and EPSRC
Real Wage Responsiveness to Unemployment in Spain: Asymmetries Along the Business Cycle
We estimate real wage cyclicality in the period compressed between 1987 and 2013 using a large administrative dataset of workers in Spain. Real wages are weakly procyclical in Spain and focusing on differences in different phases of the business cycle, we find that differences across expansions and recessions are significant, with an even lower real wage cyclicality in recessions. Furthermore, higher levels of unemployment do not translate into additional real wages adjustments when the economy is contracting, while lower levels of unemployment during expansions have incremental effects on wage elasticity. This general result holds after accounting for differences in tenure, type of contract and age categories. Nevertheless, wages of newly-hired workers are the most sensitive to the business cycle and exhibit the lowest asymmetric pattern between expansions and recessions. At the other end, wages of workers with more than six years of tenure can be characterized as the most protected against economic downturns. The same is true for fixed-term vs. permanent workers, as well as for young vs. older workers
Greenhouse gas emissions from a Western Australian finfish supply chain
Greenhouse gas (GHG) emissions in the form of carbon dioxide equivalent (CO2 - eq) from two Western Australian finfish supply chains, from harvest to retail outlet, were measured using streamlined life cycle assessment methodology. The identification of interventions to potentially reduce the GHG emissions was determined from the results obtained. Electricity consumption contributed to the highest GHG emissions within the supply chains measured, followed by refrigeration gas leakage and disposal of unused fish portions. Potential cleaner production strategies (CPS) to reduce these impacts included installing solar panels, recycling the waste, good housekeeping in refrigeration equipment maintenance, and input substitution of refrigeration gas. The results show a combination of these strategies have the potential to reduce up to 35% of the total GHG emissions from fillet harvest, processing and retail
Life cycle assessment of European anchovy (Engraulis encrasicolus) landed by purse seine vessels in northern Spain
Purpose: The main purpose of this article is to assess the environmental impacts associated with the fishing operations related to European anchovy fishing in Cantabria (northern Spain) under a life cycle approach. Methods: The life cycle assessment (LCA) methodology was applied for this case study including construction, maintenance, use, and end of life of the vessels. The functional unit used was 1 kg of landed round anchovy at port. Inventory data were collected for the main inputs and outputs of 32 vessels, representing a majority of vessels in the fleet. Results and discussion: Results indicated, in a similar line to what is reported in the literature, that the production, transportation, and use of diesel were the main environmental hot spots in conventional impact categories. Moreover, in this case, the production and transportation of seine nets was also relevant. Impacts linked to greenhouse gas (GHG) emissions suggest that emissions were in the upper range for fishing species captured with seine nets and the value of global warming potential (GWP) was 1.44 kg CO2 eq per functional unit. The ecotoxicity impacts were mainly due to the emissions of antifouling substances to the ocean. Regarding fishery-specific categories, many were discarded given the lack of detailed stock assessments for this fishery. Hence, only the biotic resource use category was computed, demonstrating that the ecosystems' effort to sustain the fishery is relatively low. Conclusions: The use of the LCA methodology allowed identifying the main environmental hot spots of the purse seining fleet targeting European anchovy in Cantabria. Individualized results per port or per vessel suggested that there are significant differences in GHG emissions between groups. In addition, fuel use is high when compared to similar fisheries. Therefore, research needs to be undertaken to identify why fuel use is so high, particularly if it is related to biomass and fisheries management or if skipper decisions could play a role.The authors thank the Ministry of Economy and Competitiveness of the Spanish Government for their financial support via the project GeSAC-Conserva: Sustainable Management of the Cantabrian Anchovies (CTM2013-43539-R) and to Pedro Villanueva-Rey for valuable scientific exchange. Jara Laso thanks the Ministry of Economy and Competitiveness of Spanish Government for their financial support via the research fellowship BES-2014-069368 and to the Ministry of Rural Environment, Fisheries and Food of Cantabria for the data support. Dr. Ian Vázquez-Rowe thanks the Peruvian LCA Network for operational support. Reviewers are also thanked for the valuable and detailed suggestions. The work of Dr. Rosa M. Crujeiras has been funded by MTM2016-76969P (AEI/FEDER, UE)
Worker Flows in the European Union During the Great Recession
We measure the contribution of worker flows across employment, unemployment, and non-participation to the change in unemployment in eleven EU countries during the period 2006-2012, paying special attention to which socio-demographic groups in each of the countries were mostly affected by job creation and job destruction during the crisis. We find that age, to a larger extent than educational attainments, is the main determinant of flows from employment into unemployment, particularly in those countries where unemployment increased by most. Secondly, we highlight some institutional features of the labour market (employment protection legislation, unemployment insurance, and the incidence of active labor market policies) that help to explain the cross-country differences in flows between employment and unemployment and in their socio-demographic composition. Finally, we examine if the crisis has led to some employment reallocation across sectors, finding that, so far, there is no clear evidence in favor of cleansing effects
Environmental supply chain management in the seafood industry: past, present and future approaches
This review discusses and analyses previous results in identification, development and implementation of cleaner production strategies within the seafood industry. The relevant peer reviewed articles were identified from a structured keyword search and analysed by both supply chain stage (capture and aquaculture, transport, processing, storage and retail), and examination of the cleaner production strategies implemented. Results found entities along the seafood supply chain generally worked separately to improve cleaner production processes and outputs to grow their own businesses. Whilst this approach can be beneficial, it ignores the broader cleaner production potential benefits gained when applied across multiple supply chain entities. The most effective cleaner production strategies for improved environmental performance in each sector of the supply chain were identified with the potential to reduce unnecessary handling, energy usage, storage costs and waste production. To ensure the greatest reduction in environmental impact, a whole of supply chain management system that incorporates life cycle assessment modelling is recommended
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