Search

The increasing use of forest biomass as a fuel for power plants due to environmental concerns will certainly increase the amount of woody biomass ash produced. Because of the environmental problems derived from woody biomass ash disposal, an important aspect for the sustainable development of the energy sector is the implementation of effective ash management strategies. The purpose of this study is to assess the environmental impacts of woody biomass ash landfarming for soil amelioration through a Life Cycle Assessment. The baseline scenario corresponds to the current most common practice of woody biomass ash management (landfilling), and two different landfarming alternatives were assessed: liming and fertilisation. Credits were given to the system due to the substitution of three traditional liming products and five traditional fertilisers. Woody biomass ash landfarming presented satisfactory performance in five impact categories under study in comparison to landfilling. When woody biomass ash was used for liming, the environmental savings were more pronounced when substituting hydrated lime. For potassium supply, the substitution of potassium nitrate by woody biomass ash presented the best environmental performance, while for phosphorus supply, the environmental savings were more pronounced substituting single superphosphate. However, in four impact categories, the environmental impacts of ash landfarming exceeded the impacts of ash landfilling, due to the emission to soil of nutrients and trace elements to soil. But this does not necessarily imply increased risks for the environment, as the potential pollutants leaching depends on their bioavailability in the soil.

In order to promote sustainable energy systems, decision-makers should take responsible choices across the entire product system, taking into account not only economic and environmental criteria but also social indicators. This is especially critical in bioenergy systems since they usually involve complex supply chains. However, this “supply-chain” perspective is not often considered when putting into practice Social Life Cycle Assessment (S-LCA) of product systems. This study presents a novel approach that enlarges the scope of conventional life cycle inventories (LCIs) in order to identify supply-chain paths within the boundaries of a product system. Conventional LCIs allow defining the main flows of components, materials and/or energy throughout the supply chain of a product, while the additional use of trade databases helps identify the country of origin of these flows. After the identification of the product's supply-chain paths, the social LCI of the product system is further ellaborated with economic and social data. This approach was tested through the S-LCA of bioelectricity in Portugal, thereby encompassing more than 400 processes within seven tiers of the supply chain. Social life cycle impact assessment results include child labour, frequency of forced labour, gender wage gap, women in the sectoral labour force and health expenditure, using the PSILCA database and method. Potential social impacts were found to be concentrated in the following processes: ammonia and N-based fertiliser production in Algeria; crude oil extraction in Russia, Kazakhstan, Saudi Arabia, and Azerbaijan; and operation and construction of the bioelectricity plant in Portugal.

The management of vineyards depends on the use of plant protection agents. Regardless of the numerous environmental impacts that these pesticides generate during their production, their dosage as pest control agents in vineyards causes an important toxic effect that must be monitored. Copper-based inorganic pesticides are the most widely used agents to control fungal diseases in humid wine-growing regions. It is, however, significant that the environmental analysis of their use through the Life Cycle Assessment (LCA) methodology does not provide detailed information on the potential toxicity of this type of pesticides. Hence, most studies report average values for copper characterization factors (CFs), excluding local soil characteristics. The objective of the study was the spatial characterization of the ecotoxicity factors of copper soil emissions as a function of the chemical characteristics of vineyard soils located in Portugal and Galicia (NW Spain). A multiple linear regression model was applied to calculate the comparative toxic potential. Subsequently, CFs for copper were calculated based on spatial differentiation considering the variable properties of the soil within each wine appellation. The CFs obtained for the area evaluated ranged from 141 to 5937 PAF·m3·day/kgCu emitted, for fibric histosols (HSf) and dystic cambisols (CMd), respectively. Moreover, the average values obtained for Galician and Portuguese soils were 1145 and 2274 PAF·m3·day/kgCu emitted, respectively. The results obtained illustrate the high variability of CF values as a function of the chemical characteristics of each type of soil. For example, Cu soil mobility was linked to organic carbon content and pH. Finally, to validate the representativeness of the calculated CFs, these were applied to the results of 12 literature life cycle inventories of grape production in the area evaluated, revealing that impact scores associated with Cu emissions can considerably vary when spatially-differentiated CFs are implemented. published

Ash generated during the combustion of woody biomass for energy production is an industrial waste that should be properly managed in order to minimise the respective environmental impacts. Woody biomass ash valorisation in construction materials to replace conventional materials is an alternative that has proven to be technically feasible. On the other hand, it can present potential environmental impacts that should be evaluated to support the choice of more sustainable alternatives. Thus, the purpose of this work is to assess the potential impacts of woody biomass ash valorisation of through incorporation in construction materials using life cycle assessment. The valorisation alternatives consider the incorporation of woody biomass ash in cement mortars, adhesive mortars, concrete blocks, and bituminous asphalts. In addition, a base scenario consisting of ash landfilling is also assessed. Four types of woody biomass ashes were considered, namely fly and bottom ashes generated in a vibrating grate and fly and bottom ashes generated in a fluidised bed. The impact assessment method used is that suggested in the International Reference Life Cycle Data System for selected impact categories. The results showed that the impacts of ash transport and pre-processing and the impacts of producing the avoided materials are factors that affect the net impact of the valorisation scenarios and should be considered in the end-of-life management of biomass ash. Nevertheless, all valorisation scenarios had a lower impact than landfilling in all the impact categories under study, resulting in a significant decrease of the environmental impacts in some scenarios.

The automobile industry is demanding new car components to reduce vehicle emissions and increase efficiency. Lightweighting strategies are the most followed by manufacturers to reduce the weight and fuel consumption of vehicles. In this study, an innovative signal cable solution for the wire harnesses of vehicle is analysed through a life cycle assessment (LCA) and benchmarked with the replaced cable. The innovative cable is made up of a copper-tin alloy, while the traditional cable is made of copper. Both products are twisted and insulated with plasticised polyvinyl chloride. The new cable reduces the weight and volume by 53% and 41%, respectively, compared to the traditional cable. The production of raw and ancillary materials was found to be the main impact contributor, mainly due to the production of the conductive and insulation materials. Similarly, electricity consumption was the main impact carrier for the manufacturing stage. The environmental burdens obtained for the innovative cable were, on average, 54% lower than those obtained for the replaced one. Additionally, the potential marginal gains for the automobile industry were evaluated in terms of fuel consumption reduction, which is linked to vehicle weight, and the derived emissions, obtaining a significant exhaust emission reduction of 160 kg CO2 eq when compared to the baseline scenario. Finally, the LCA of these products was decisively influenced by the consumption of raw materials and, therefore, the reduction of the thickness of the wire makes the cables considerably more sustainable from an environmental point of view.

Electricity production from biomass has the potential to significantly contribute to the share of renewable energy in the global power mix with lesser environmental impact than non-renewable resources. The production of bioenergy from forest biomass residues is currently increasing in Portugal, mainly as a consequence of concerns related to climate change and forest fires. In Portugal, the annual production of residual biomass from forest logging is estimated at 0.8-1.2 million dry tons per year, and about 47-58% of these residues come from eucalypt. This study evaluates the environmental impacts resulting from electricity production in Portugal using eucalypt logging residues (composed of branches, foliage and tops) and considering two types of technologies: grate furnaces and fluidised bed furnaces. This assessment was performed using life cycle assessment (LCA) methodology, a methodology that evaluates the environmental impacts entire life cycle of a product or process (from the extraction of the raw materials until its end-of-life), allowing to identify the most significant stages and processes along the life cycle, and supporting by this way the decision and policy-making.Two alternative scenarios for biomass-to-energy conversion technologies were simulated: grate furnace and fluidised bed furnace. The functional unit is the production of electricity from the combustion of eucalypt logging residues equivalent to 1 kWh delivered by the power plant to the Portuguese grid. System boundaries include the following stages: (1) forest management (including site preparation, planting, stand tending and logging); (2) residues collection; and (3) energy conversion (including forest biomass combustion as well as treatment and final destination of wastes). Seven impact categories from the International Reference Life Cycle Data System (ILCD) are considered: climate change, particulate matter, photochemical ozone formation, acidification, freshwater eutrophication, marine eutrophication and mineral and fossil resource depletion.The results show that the forest management stage had a low contribution to the total impact in all impact categories for both technologies under analysis. The only exception is the impact category of mineral and fossil depletion, in which forest management is mainly responsible and which accounts for 92-94% of the total impact for both technologies analysed. The energy conversion is the hotspot in most of the impacts studied (climate change —49-63%, particulate matter —94-95%, photochemical ozone formation —85-88% of, acidification —76-79%, freshwater eutrophication —56-58% and marine eutrophication —70-71% of the total impact) and therefore, this is the stage for which improvements should be primarily establishedestablished for both technologies analysed. In addition, for all impact categories analysed, the fluidised bed presented the smallest environmental impact. Even when the grate furnace efficiency increases and the fluidised bed efficiency decreases in a sensitivity analysis, the fluidised bed has lower impacts than the grate furnace and is a good alternative for implementing new power plants. Further research is needed to analyse the effects of converting the grate technology in Portugal to fluidised bed technology.

Recently, wood pellets have become a reliable and clean renewable fuel for residential heating, replacing fossil fuels and reducing greenhouse gas emissions. Wood pellets are normally produced in industrial pellet plants (centralised production), but decentralised small-scale local production also occurs. This study applies Life Cycle Assessment (LCA) to quantify and compare the environmental profile of one centralised and two decentralised alternatives for wood pellet production for residential heating in Portugal: (1) industrial wood pellets production (centralised), (2) wood pellets production at sawmills (decentralised) and (3) wood pellets production at households (decentralised). System boundaries include the stages of forest management, wood pellet production, wood pellet distribution and wood pellet energetic conversion. The impact results show that industrial pellet production ranks as the worst alternative, while pellet production at households has the best environmental profile for all the impact categories under study. However, the environmental impacts of pellet production at the sawmill do not differ greatly from those of the pellet production at households; they are 14 to 16% higher for global warming and fossil resources scarcity and 0.3 to 3% higher for the remaining impact categories. The worst environmental performance of the industrial pellet production alternative is mainly due to high electricity and diesel consumption during wood pellet production and the use of logging residues to generate heat for drying biomass feedstock. A sensitivity analysis was performed to evaluate the influence of changing the distance travelled during the transport of packed pellets to stores and sawdust to households. The results show changes in the environmental performance ranking, highlighting that for short distances, both decentralised alternatives can be more sustainable from an environmental perspective than the centralised alternative, but for larger distances, the pellet production at households should be avoided.

Moving towards a global bioeconomy can mitigate climate change and the depletion of fossil fuels. Within this context, this work applies a set of multi-criteria decision analysis (MCDA) tools to prioritise the selection of five alternative bioenergy systems for residential heating based on the combination of three commercial technologies (pellet, wood stove and traditional fireplace) and two different feedstocks (eucalypt and maritime pine species). Several combinations of MCDA methods and weighting approaches were compared to assess how much results can differ. Eight indicators were used for a sustainability assessment of the alternatives while four MCDA methods were applied for the prioritisation: Weighted Sum Method (WSM), Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), Elimination and Choice Expressing Reality (ELECTRE), and Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE). Regarding the sustainability performance indicators, the highest environmental impacts were calculated for the fireplace alternatives, and there was not a best environmental option. Also, no clear trend was found for the economic and social dimensions. The application of MCDA tools shows that wood stove alternatives have the best sustainability performance, in particular wood stove with combustion of maritime pine logs (highest scores in the ranking). Regarding the worst alternative, fireplaces with combustion of eucalypt logs ranked last in all MCDA rankings. Finally, a sensitivity analysis for the weighting of the performance indicators confirmed wood stoves with combustion of maritime pine logs as the leading alternative and the key role of the analysts within this type of MCDA studies.

The development of methods to assess the potential environmental impact of green water consumption in life cycle assessment has lagged behind those for blue water use, which are now routinely applied in industrial and policy-related studies. This represents a critical gap in the assessment of land-based production systems and the ability to inform policy related to the bio-economy. Combining satellite remote sensing and meteorological data sets, this study develops two new sets of spatially-differentiated and globally applicable characterisation factors (CFs) to assess the environmental impact of green water flows in LCA. One set of CFs addresses the impact of shifts in water vapour flow by evapotranspiration on blue water availability (CFWS) and the other set of CFs addresses moisture recycling within a basin (CFWA). Furthermore, as an additional and optional step, these two indicators are combined into an aggregated green water scarcity indicator, representing the global variability of green water scarcity. The values obtained for CFWA show that there are significant changes in green water flows that were returned to the atmosphere in Alaska (covered by open shrublands) and in some central regions of China (covered by grasslands and barren or sparsely vegetated land), where precipitation levels are lower than 10 mm/yr. The results obtained for CFWS indicate that severe perturbations in surface blue water production occur, particularly in central regions of China (covered by grasslands), the southeast of Australia (covered by evergreen broadleaf forest) and in some central regions of the USA (covered by grassland and evergreen needleleaf forest). The application of the green water scarcity CFs enables the evaluation of the potential environmental impact due to green water consumption by agricultural and forestry products, informing both technical and non-technical audiences and decision-makers for the purpose of strategic planning of land use and to identify green water protection measures.

The water footprint profile was analyzed for grape used in vinification in the Ribeiro appellation (Spain) for the period 2000–2009. The ISO 14046 framework was followed to address the quantitative —freshwater scarcity— and qualitative —degradation— water-related impacts from a life cycle perspective. The timeline perspective allowed the analysis of the fluctuation of impacts for this kind of product. For the quantitative blue water-related impacts, the Available WAter REmaining (AWARE) method was implemented to assess the freshwater scarcity impacts, being the selection of characterization factors (CFs) essential to establish the main impact contributors, especially for direct water consumption at spatial scale. Blue water scarcity impact results varied considerably during the period assessed, mainly due to changes in the harvest yield. The impact results obtained from the AWARE method were compared with the results obtained with other water-related impact assessment methods —water stress index and water depletion. The results for both share the same trends as the AWARE method, with direct water consumption representing 30%–40% of the total contributions throughout the assessed period. The green water scarcity footprint was also evaluated, showing that there are perturbations in the production of surface blue water and green moisture recycled to the atmosphere. The sensitivity analysis on green water CFs showed high variations in green water scarcity footprint results, highlighting the relevance of deriving spatially differentiated and crop-specific green water CFs to assess real water consumption impacts on crop fields properly. On-field emissions were the primary responsible for water degradation impacts; in particular, those resulting from fuel consumption, pesticides application and fertilization. The sensitivity analysis conducted for pesticides emissions highlighted the necessity of a consensus dispersion model to address them.

Purpose The aim of the present study is to assess the influence of two different attributional life cycle assessment (LCA) approaches, namely static LCA (sLCA) and dynamic LCA (dLCA), through their application to the calculation of the carbon footprint (CF) of the entire cork sector in Portugal. The effect of including biogenic carbon sequestration and emissions is considered as well. Methods sLCA is often described as a static tool since all the emissions are accounted for as if occurring at the same time which may not be the case in reality for greenhouse gases. In contrast, dLCA aims to evaluate the impact of life cycle greenhouse gas emissions on radiative forcing considering the specific moment when these emissions occur. Results and discussion The results show that the total CF of the cork sector differs depending on the approach and time horizon chosen. However, the greater it is the time horizon chosen, the smaller the difference between the CF results of the two approaches. Additionally, the inclusion of biogenic carbon sequestration and emissions also influences significantly the CF result. The cork sector is considered a net carbon source when biogenic carbon is excluded from the calculations and a net carbon sink when biogenic carbon is included in the calculations since more carbon is sequestered than emitted along the sector. Conclusions dLCA allows an overview of greenhouse gas emissions along the time. This is an advantage as it allows to identify and plan different management approaches for the cork sector. Even though dLCA is a more realistic approach, it is a more time-consuming and complex approach for long life cycles. The choice of time horizon was found to be another important aspect for CF assessment. published

Summary To support effective urban policies aimed at decreasing the environmental impacts of cities, it is important to develop robust tools for accounting those impacts. Environmentally extended input-output analysis (EEIOA) is among the most used tools for this purpose, allowing the quantification of both direct and indirect impacts. Life cycle assessment (LCA) is also a holistic and comprehensive tool that accounts for direct and indirect impacts—but its application to cities is still very recent. This study aims at applying EEIOA and LCA to the municipality of Aveiro (Portugal) in order to compare the outcomes of the two tools in terms of total impacts (climate change and fossil fuel depletion) and hotspots (sectors/products contributing most to the impacts), to identify limitations and advantages of the tools when applied to Aveiro, and to illustrate how LCA can be applied to cities. The total impacts estimated with LCA and EEIOA were similar and the hotspots were also the same: transports, food, construction, and electricity. However, the relative contribution of some sectors was very different in the two tools due to methodological differences mainly in system boundaries, type of activities or products considered in each sector, and geographical coverage of impact data. This study concludes that the analyzed tools can provide complementary results to support decision making concerning urban planning and management.

This work presents a systematic review, updating the information on the currently available methods to calculate the water footprint (WF), and addressing the following methodological challenges, as they have not been deeply studied to date: (1) accounting and assessing the environmental impacts related to changes in evapotranspiration (ET); (2) inventory of actual blue freshwater consumption in agriculture; (3) temporal and spatial variation to establish explicit characterisation factors (CFs) and (4) adequate connection between inventory flows and spatio-temporal explicit CFs. A systematic review relying on the guidelines of Pullin and Stewart (Conserv Biol 20(6):1647–1656, 2006) was conducted. Taking into account five specific formulated research questions in the WF field, WF studies were selected based on two ‘types’ of screening criteria: keyword searches and the WF study filter. From the 128 papers in peer-reviewed journals on product WF from a life cycle perspective, this literature review shows that major methodological challenges remain partially unsolved, which could degrade the accuracy of product WF assessments. To understand how land use affects ET, and depending on the land cover and size of the land use production system, actual ET can be estimated based on meteorological data on water balance equations embedded in crop and forest growth models, from field measurements at meteorological stations and more recently from remote sensing. For accounting for blue water consumption in agriculture, there are two types of approaches that lead to quite different results: inventory from actual farming records of applied irrigation and inventory from modelled ET associated with irrigation. Depending on the question being addressed, the practitioner can apply either approach. Furthermore, when a single freshwater scarcity CF is determined for large sub-watersheds, especially when the sub-watersheds have non-uniform freshwater availability and demand, uncertainty in the freshwater use-related impacts is introduced. Regarding the connection between inventory flows and spatio-temporal explicit CFs, the difficulty in identifying the exact location of background processes and characterising the local environmental characteristics (e.g. edaphoclimatic conditions, land cover) can hinder the elaboration of an accurate spatially differentiated impact assessment, as more generic CFs can be applied. This systematic review shows that there are clearly future research needs with respect to the interrelations between freshwater use and potential damages in the areas of protection of resources, human health and ecosystem quality. It is also of paramount importance to understand the effects of land use and land cover change and water irrigation on WF damage.

The great quantities of raw materials used in the construction sector, involve high energy consumption in their production resulting to a high energy use in this sector. One of the ways to improve the energy efficiency of buildings is through the use of more environmentally friendly materials such as forest-based materials. In the present study, the environmental impacts associated with the production of expanded cork slab and granules used in construction for insulation are evaluated from a life cycle perspective with the aim of identifying the most influential stages and processes. The obtained results show that the process with the greatest environmental impact derives from the boiler process due to the production of thermal energy used for the agglomeration of the slabs and also the production of falca used as raw material at the manufacturing process. It was also observed that the choice of mass or economic allocation has a significant impact on the results. The present study also considered the accounting of biogenic carbon in the climate change impact category which is usually considered neutral and excluded. The final results of climate change were recalculated by applying the International Reference Life Cycle Data System method for the stages of the forest, use and end-of-life. The consideration of biogenic carbon sequestration at the forest influenced significantly the environmental impact of the two products under study. The present study shows the importance of biogenic carbon inclusion in the environmental assessment of forest-based products. Additionally, the obtained results highlight the need for establishment of a common methodology for the calculation of the environmental impacts of cork products in order to apply common guidelines and facilitate the comparison of the obtained results.

Wood-fuelled systems are commonly used all over the world for residential heating, and recently wood pellets have been replacing traditional firewood. This article presents an environmental life cycle assessment of five wood-based combustion systems for residential heating: i) a pellet stove using maritime pine pellets; a wood stove using ii) eucalyptus (Eucalyptus globulus Labill.) and iii) maritime pine (Pinus pinaster Ait.) split logs; and a fireplace using iv) eucalyptus and v) maritime pine split logs. The functional unit is 1 MJ of thermal energy for residential heating. System boundaries include four stages: (1) forest management; (2) pellet and wood split log production; (3) distribution; and (4) thermal energy generation. Environmental impacts were calculated for seven impact categories from the ReCiPe 2016 midpoint method, and a sensitivity analysis was performed using the Product Environmental Footprint (PEF) life cycle impact assessment method and modifying the distances travelled. Of the five heating systems analysed, the fireplace presents the worst performance for all the impact categories with the exception of freshwater eutrophication and marine eutrophication, when maritime pine split logs are burned in the fireplace. Comparing the pellet stove with the wood stove, neither system is better for all the impact categories analysed. Regarding sensitivity analysis, the use of an alternative characterisation method leads to similar trends in the results in comparison with those obtained from the ReCiPe method, while changes in transport distances do not affect the total impacts to a large extent.

The Portuguese government's new strategy is based on the predicted increase in the country's installed electricity capacity through the use of biomass residues, including forest biomass residues. However, this strategy implies that the use of forest biomass residues in electricity production will most likely be at the expense of alternative uses, such as heat and biofuel production. Therefore, what is the best use of forest biomass residues available in the country from an environmental perspective? To answer this question, in this study, a consequential life cycle assessment was applied to assess three different scenarios: 1) the production of electricity in dedicated power plants; 2) the cogeneration of electricity and heat in combined heat and power plants; and 3) the production of bioethanol by biochemical conversion. The results showed that the strategy of using forest biomass residues for electricity production would be advantageous in relation to the baseline (i.e. leaving forest residues in forest soil and using fossil fuel sources to produce energy) only in some environmental impact categories. The results showed that the cogeneration of electricity and heat production was the best alternative among the three scenarios. However, regarding the effects related to particulate matter and marine eutrophication, the results showed that this alternative would perform better than baseline if the displaced fuels were coal in electricity production and at least 12% fuel oil (and the rest natural gas) in heat production. The conversion of forest biomass residues to bioethanol was the least beneficial regarding all categories under study.

The use of biomass pellets as fuel is emerging as a suitable alternative to fossil resources for mitigating climate change. A considerable number of articles have applied Life Cycle Assessment (LCA) to quantify and to compare the environmental performance of biomass pellets but a wide variation of results can be found in the literature. This work reviews 84 articles on LCA of biomass pellets, focusing on identifying trends in methodological choices and on understanding the influence of those choices on life cycle impacts, in particular global warming and non-renewable primary energy. Most of the reviewed articles assess woody pellets and most of the cradle-to-grave studies focus on heat generation. The methodological choices vary widely between articles with respect to approach (attributional or consequential), functional unit, system boundaries, procedure to deal with multifunctionality and allocation, biogenic carbon modelling, inclusion of greenhouse gases other than carbon dioxide, life cycle impact assessment method, impact categories, and presence of sensitivity analysis. The results for global warming and non-renewable primary energy were assessed, showing a correlation between them. Moreover, a high variability is found for global warming, with impacts ranging from −18 to 488 g CO2 eq/MJpellets. The main causes (technological features, assumptions, methodological choices) for this high variability are analysed and discussed.

This study evaluates the environmental profile of ceramic tiles produced in Portugal based on a cradle-to-grave Life Cycle Assessment (LCA), including mining, manufacturing, construction, use and final disposal. The main hotspots are identified and improvement actions are suggested in order to reduce the environmental impacts. According to the results, the major hotspot is the production stage (cradle-to-gate), for all categories except ecotoxicity and land use. Within this stage, the processes that have the greatest impact are the following: onsite activities (especially the burning of natural gas for the tile manufacturing process), transport, electricity production and production of natural gas. Among the improvement actions analyzed, the most efficient measure studied to reduce the environmental impacts was a combination of actions to reduce fuel consumption (best available technique), electricity and raw material transport distance, although the economic sustainability could be a critical issue. This work also identified the main environmental impact categories that can be used to define ceramic tiles environmental profile, thus encouraging an update of environmental communication tools based on LCA.

© 2016, Springer-Verlag Berlin Heidelberg. Purpose: This study illustrates the applicability of a framework to conduct a spatially distributed inventory of suspended solids (SS) delivery to freshwater streams combined with a method to derive site-specific characterisation factors for endpoint damage on aquatic ecosystem diversity. A case study on Eucalyptus globulus stands located in Portugal was selected as an example of a land-based system. The main goal was to assess the relevance of SS delivery to freshwater streams, providing a more comprehensive assessment of the SS impact from land use systems on aquatic environments. Methods: The WaTEM/SEDEM model, which was used to perform the SS inventory, is a raster-based empirical erosion and deposition model. This model allowed to predict the amount of SS from E. globulus stands under study and route this amount through the landscape towards the drainage network. Combining the spatially explicit SS inventory with the derived site-specific endpoint characterisation factors of SS delivered to two different river sections, the potential damages of SS on macroinvertebrates, algae and macrophytes were assessed. In addition, this damage was compared with the damage obtained with the commonly used ecosystem impact categories of the ReCiPe method. Results and discussion: The relevance of the impact from SS delivery to freshwater streams is shown, providing a more comprehensive assessment of the SS impact from land use systems on aquatic environments. The SS impacts ranged from 15.5 to 1234.9 PDF m3.yr.ha−1.revolution−1 for macroinvertebrates, and from 5.2 to 411.9 PDF.m3.yr.ha−1.revolution−1 for algae and macrophytes. For some stands, SS potential impacts on macroinvertebrates have the same order of magnitude than freshwater eutrophication, freshwater ecotoxicity, terrestrial ecotoxicity and terrestrial acidification impacts. For algae and macrophytes, most of the stands present SS impacts of the same order of magnitude as terrestrial ecotoxicity, one order of magnitude higher than freshwater eutrophication and two orders of magnitude lower than freshwater ecotoxicity and terrestrial acidification. Conclusions: The SS impact results allow concluding that the increase of SS in the water column can cause biodiversity damage and that the calculated impacts can have a similar or even higher contribution to the total environmental impact than the commonly used ecosystem impact categories of the ReCiPe method. A wide application of the framework and method developed at a local scale will enable the establishment of a regionalised SS inventory database and a deep characterisation of the potential environmental impacts of SS on local aquatic environments. ispartof: The International Journal of Life Cycle Assessment vol:22 issue:2 pages:159-171 status: published

An important aspect of sustainable development is the implementation of effective and sustainable waste management strategies. The present study focuses on a Life Cycle Assessment (LCA) approach to different waste management strategies for natural cork stoppers, namely incineration at a municipal solid waste incinerator, landfilling in a sanitary landfill, and recycling. In the literature, there are no LCA studies analyzing in detail the end-of-life stage of natural cork stoppers as well as other cork products. In addition, cork is usually treated as wood at the end-of-life stage. Thus, the outcome of this study can provide an important insight into this matter. The results showed that different management alternatives, namely incineration and recycling, could be chosen depending on the impact category considered. The former alternative presented the best environmental results in the impact categories of climate change, ozone depletion and acidification, while the latter for photochemical ozone formation and mineral and fossil resource depletion. The landfilling alternative did not present the best environmental performance in any of the impact categories. However, when the biogenic carbon dioxide emission was assessed for the climate change category, the landfilling alternative was found to be the most effective since most of the biogenic carbon would be permanently stored in the cork products and not emitted into the atmosphere. A sensitivity analysis was performed and the results showed that there are various parameters that can significantly influence the results (e.g., carbon content in cork and decay rate of cork in the landfill). Thus, LCA studies should include a detailed description concerning their assumptions when the end-of-life stage is included in the boundaries since they can influence the results, and furthermore, to facilitate the comparison of different end-of-life scenarios. The present study and the obtained results could be useful for the decision-making process concerning public solid waste policies and industrial strategies.

This paper compares the water footprint profiles of four feedstocks used for biodiesel production: palm, soya, rapeseed and waste cooking oil (WCO). The profiles include: (a) a water scarcity footprint related to freshwater consumption impacts and (b) a water quality degradation footprint related to freshwater degradation impacts. The water scarcity footprint was assessed using two impact assessment methods: one based on water stress indices (WSIs) and the other on the available water remaining (AWARE) indicator. The water degradation footprint was assessed considering the environmental mechanisms covered by the impact categories of eutrophication, aquatic acidification, human toxicity and freshwater ecotoxicity. The water scarcity profiles ranged from 0.002 to 2.11 world m3eq kg−1 oil (WSI method) and from 0.008 to 133.57 world m3eq kg−1 oil (AWARE method). Both methods showed that the cultivation stage assumes the primary role in the water scarcity footprint results and identified the same systems with higher water scarcity footprints. However, for the oil systems with closer results, the rank order given by each method is different due to the characterization factors of each method. Nevertheless, the results obtained with the AWARE method give more comprehensive water scarcity footprint results than those obtained when applying WSIs because AWARE considers the aquatic ecosystem water demand. The water degradation footprint of virgin oils is mainly caused by fertilizers and pesticides used in cultivation. WCO systems present lower impacts for all impact categories with the exception of human toxicity-cancer. The choice of locations with lower water scarcity to produce oil crops can be a determinant in the calculation of lower impacts. Moreover, optimizing fertilization schemes or choosing climatic conditions that require less fertilizers, pesticides and water consumption can reduce the impacts of the water footprint profile of vegetable oils.

The potential effects of future climate in green freshwater resources are an issue that needs to be addressed. The main goal of this study is to evaluate how future climate will affect green water scarcity resources, by calculating green water scarcity characterisation factors (CFs) under a reference (period 1986 to 2005) and a medium-term future (period 2046 to 2065) climate, based on the principles established by Quinteiro et al. (2018). This study considers a higher spatial resolution (9 × 9 km) than Quinteiro et al. (2018), improving the knowledge of green water scarcity conditions in mainland Portugal. The CFs were calculated considering two different interfaces: (1) interface green freshwater – topsoil (ws), and; (2) interface green freshwater – atmosphere (wa). At the interface ws, the relation between the changes on green freshwater flows and the surface blue freshwater recharge is considered, while at the interface wa the relation between the evapotranspiration (ET) recycled to the atmosphere and the precipitation levels at the same watershed level are considered. The green freshwater scarcity CFs were developed based on ET values, which in turn were calculated based on meteorological variables obtained with the Weather Research and Forecasting (WRF) model. Some regions of Portugal are currently suffering of pressure on green freshwater resources (mainly in Central littoral and Western coastal areas). In general, green freshwater scarcity CFs is projected to increase in Portugal under future climate in comparison to the CFs obtained for reference conditions. Green freshwater scarcity CFs at the interface ws increase from 101 to 150%, while CFs at the interface wa increase from 301 to 800%. These results show that strategies and policies to support the management of green freshwater resources and land use planning, ensuring the highest level of freshwater productivity of crops and forests, should be developed.

Electricity production from biomass has the potential to significantly contribute to the power mix in Portugal with lesser environmental impact than non-renewable resources. This study focuses on electricity production from the combustion of residual forest biomass from eucalypt logging activities in Portugal using life cycle assessment. In Portugal, several power plants fuelled by residual forest biomass have been commissioned in the last few years. Most of the installations use fluidised bed furnaces, and the others use grate furnaces. This study aims to compare the environmental impacts associated with these two alternative combustion technologies. System boundaries include the stages of forest management, collection processing and transportation and energy conversion. The default impact assessment method used is that suggested in the International Reference Life Cycle Data System. In a sensitivity analysis, calculations are performed using the ReCiPe method. For all of the impact categories analysed, the fluidised bed presents the smallest environmental impact. Even when the grate furnace efficiency increases and the fluidised bed efficiency decreases in the sensitivity analysis, the fluidised bed has lower impacts than the grate technology and can be the best alternative in the implementation of new power plants.

The objective of this study is to evaluate of the environmental impacts associated with the manufacturing process of a cork floating floor, produced in Portugal, in order to identify the most significant stages and processes (hotspots) with the aim of improving the manufacturing process and the sustainability of the product.Life Cycle Assessment methodology is used by applying a cradle-to-gate approach. The results show that the stage with the highest environmental impact is the assembling stage (where all the product’s components are assembled) mainly due to the production of high density fiberboard.Additionally, the present study discusses the currently hot and controversial issue of biogenic carbon considering its storage in products and emission delay. For this part of the study a cradle-to-gate approach was adopted and three leading methodologies were compared, namely, Greenhouse Gas Protocol Product Standard, Publicly Available Specifications 2050 and the International Reference Life Cycle Data System. The results show that the choice of methodology has an important influence on the results obtained both for biogenic carbon dioxide emissions and carbon storage. This highlights the need for the establishment of a common methodology for the calculation of biogenic carbon, not only for the homogeneity of the guidelines but also for the ease of comparing results. Keywords: Biogenic carbon, Cork flooring, Environmental impact, Life Cycle Assessment, Portugal

The aim of this study was to provide a detailed environmental evaluation of pigmeat production (the second most widely eaten type of meat) in Portugal, using relevant and good quality data in order to obtain representative results for this production sector. Life cycle assessment (LCA) methodology was used for the evaluations from a cradle-to-slaughterhouse gate perspective. The system under study was divided in three subsystems: crop and feed production (S1), pigmeat production (S2) and slaughtering (S3). The production system under study considered the Best Available Techniques (BATs) for intensive rearing of pigs. According to the results and in line with other studies, S1 was the most influential subsystem in the environmental profile (ranging from 70% to 100% depending on the impact) mainly due to agricultural activities involved in the production of feed components. Activities carried out on the pig farms (S2) were remarkable in categories such as climate change due to background processes involved in the production of electricity requirements, e.g. emissions derived from slurry management (such as CH4 and N2O), and water depletion. Slaughtering-related contributions were negligible regardless of the category assessed. Different alternatives for the valorisation of animal by-products derived from the slaughterhouse were proposed for energy and feed production. A comparison with other related studies focused on pigmeat production was performed and no remarkable differences were identified. Thus, achievements and environmental hotspots identified in this specific case study for Portugal could be extended to the European production chain.

The cultivation of three different cereals – wheat, triticale and maize (five classes: 300, 400, 500, 600 and 700) – dedicated to grain production for feed purposes was assessed to quantify their environmental profiles and identify the most sustainable crop from an environmental perspective. The most critical processes throughout the life cycle of the cropping systems were also identified. These cereals were chosen because they are the most widespread cereal crops in the Po Valley (Lombardy region), the most important agricultural area in Italy. The standard framework of the Life Cycle Assessment (LCA) was followed to assess the environmental performance of the different cropping systems. Several impact categories were evaluated, including climate change (CC), ozone depletion (OD), terrestrial acidification (TA), freshwater eutrophication (FE), marine eutrophication (ME), human toxicity (HT), photochemical oxidant formation (POF), terrestrial ecotoxicity (TEC), freshwater ecotoxicity (FEC), marine ecotoxicity (MEC), water depletion (WD), fossil depletion (FD) as well as land use as an indicator. The results showed that the maize class 300 was the cereal with the worst environmental profile in the base case, considering economic allocation and no environmental burdens related with digestate production. This scenario presented the most intensive agricultural practices and the lowest biomass yield in comparison with the other crops. In contrast, the maize classes 600 and 700 were the cereal crops with the best environmental profiles in most impact categories. The lower requirements of fertiliser (and thus, fertilisation activities) as well as the higher biomass yield were responsible of these favourable results. However, according to the environmental results, the selection of the best biomass source depends on several methodological assumptions such as the functional unit and the allocation criteria considered (between the grain and the straw) as base for the calculations. Thus, the results of a sensitivity analysis showed that the choice of a mass allocation instead of economic one caused lower environmental impacts in all the categories. Moreover, the consideration or not of the environmental burdens related to the digestate production (the main organic fertiliser used) was also a critical step in the environmental evaluations. The inclusion of environmental loads related to digestate production caused a notable increase in the impact of all the cropping systems regardless the cereal and the impact category. This conclusion could be extrapolated to other systems that exclude the additional burdens allocated to the production of organic fertilisers.

This work studied the influence of effluent recirculation upon the kinetics of anaerobic degradation of dairy wastewater in the feedless phase of intermittent upflow anaerobic sludge bed (UASB) reactors. Several laboratory-scale tests were performed with different organic loads in closed circuit UASB reactors inoculated with adapted flocculent sludge. The data obtained were used for determination of specific substrate removal rates and specific methane production rates, and adjusted to kinetic models. A high initial substrate removal was observed in all tests due to adsorption of organic matter onto the anaerobic biomass which was not accompanied by biological substrate degradation as measured by methane production. Initial methane production rate was about 45% of initial soluble and colloidal substrate removal rate. This discrepancy between methane production rate and substrate removal rate was observed mainly on the first day of all experiments and was attenuated on the second day, suggesting that the feedless period of intermittent UASB reactors treating dairy wastewater should be longer than one day. Effluent recirculation expressively raised the rate of removal of soluble and colloidal substrate and methane productivity, as compared with results for similar assays in batch reactors without recirculation. The observed bed expansion was due to the biogas production and the application of effluent recirculation led to a sludge bed contraction after all the substrates were degraded. The settleability of the anaerobic sludge improved by the introduction of effluent recirculation this effect being more pronounced for the higher loads.

The increasing scarcity of freshwater in many parts of the world triggered a growing concern about freshwater use and its quality degradation. Currently, a number of methods to assess the potential environmental harm in ecosystems services derived from freshwater use are available under the framework of Life Cycle Assessment (LCA). In this study, the assessment of the quantitative freshwater use impact of a Portuguese wine (white ‘vinho verde’) was undertaken using the methods suggested by: Pfister et al. (2009), Frischknecht et al. (2009a, b), Ridoutt et al. (2010), and Mila i Canals et al. (2009). These methods differ significantly concerning the type of freshwater, freshwater scarcity level, and characterisation factors considered. The quantitative freshwater use of white’ vinho verde’ considering both viticulture and wine production stages (disaggregated into foreground and background sub-systems) is analysed at the inventory and impact assessment levels. Moreover, the freshwater footprint profile i.e. the compilation of quantitative and degradative environmental impacts related to freshwater use is also evaluated. The inventory results of freshwater use obtained by the Mila i Canals et al. (2009) method differ significantly from the ones obtained by other used methods due to the consideration of land use effects. At the impact assessment level, a large variability for the freshwater use impact was obtained, mainly due to different characterisation factors considered by each method. Besides, the background sub-systems arise as the major hotspots for all methods other than that proposed by Mila i Canals et al. (2009) and for all degradative impact categories other than eutrophication.

The environmental impacts derived from the urban water system of the municipality of Aveiro (Portugal) were analysed in this study using the Life Cycle Assessment (LCA) methodology. In addition, those stages and processes with the largest environmental impacts were identified and improvement scenarios were proposed. The entire water system was considered, including the following stages: water abstraction and treatment, water distribution, sewage collection, wastewater treatment and disposal, and water administration. The results show that the stage of water abstraction and treatment was the most relevant for the majority of impact categories because most of the electricity consumption happened during this stage. For marine eutrophication and marine ecotoxicity, the stage of wastewater treatment and disposal alone carried almost the entire burden because of the release of nitrogen and phosphorus into the sea. Electricity consumption and discharge of nutrients to the sea have been identified as the largest contributors to the environmental impacts. Therefore, scenarios focused on changing these burdens were assessed in order to prioritise those actions that would bring the greatest improvements. The proposed improvement actions could be a basis for the decision-making process regarding future investments towards environmental sustainability of the urban water system. The financial support of the European Commission, through the Erasmus Mundus Program, is acknowledged for the master scholarship granted to Diogo Siqueira Lemos in the Joint European Master in Environmental Studies (JEMES). The authors would also like to thank FCT (Science and Technology Foundation – Portugal) for the scholarships granted to Ana Cláudia Dias (SFRH/BPD/20363/2004 and SFRH/BPD/75788/2011) and the project ECOTECH SUDOE – International network on LCA and ecodesign for eco-innovation (SOE2/P2/E377) funded by the EU Interreg IV B Sudoe Program. Thanks also to the entities Águas do Vouga, ADRA, SIMRIA and Serviços Municipalizados de Aveiro for providing real data. published

Bioenergy is becoming increasingly important for agriculture. However, the use of first generation crops for biofuels and bioenergy production is controversial due to their competition with food and feed. The cultivation of three different energy crops – wheat, maize and triticale – for biomass in order to produce biogas in Lombardy, in the Po Valley (Italy), was evaluated in this study to quantify their environmental profiles and identify the best biomass source from an environmental perspective. The choice of these cropping systems was based on the fact that they are well-known and extensively cultivated for energy purposes in Italy. The standard framework of the Life Cycle Assessment (LCA) was followed in this study and detailed inventories for these crops were designed. The environmental profile was analysed in terms of abiotic depletion, acidification, eutrophication, global warming, ozone layer depletion, photochemical oxidants formation, human toxicity and ecotoxicity. In addition, an energy analysis was performed using the cumulative energy demand method. According to the results, the selection of the best biomass source depends on several factors such as the functional unit and biomass yield. Therefore, a sensitivity assessment was done in order to identify these differences. Moreover, the most critical processes throughout the life cycle of the cropping systems were identified and improvement alternatives were proposed, specifically for the mineral fertilization (one of the most important hot spots). Thus, different scenarios built on alternative nitrogen based fertilizers were assessed in detail and discussed, resulting in the identification that the use of calcium ammonium nitrate instead of urea should improve the environmental profile regardless of the energy crop. Finally, the combination of triticale or wheat with maize classes 300, 400 and 500 in rotation systems was done in order to achieve similar biomass yields, per ha, to the maize classes 600 and 700, which were also evaluated. The best results were obtained for maize classes 600 and 700 regardless of the functional unit considered in all the categories assessed except in GWP, where triticale with maize 400 and with maize 500 were the best options.

In the present study, a simulation model for the calculation of the carbon footprint of the cork oak sector (CCFM) is developed for the first time. A life cycle approach is adopted including the forest management, manufacturing, use and end-of-life stages. CCFM allows the user to insert the cork type used as raw material and its respective quantity and the distances in-between the various stages. The user can choose among different end-of-life destination options for the used cork products. The option of inserting different inputs, allows the use of the present simulation model for different cork oak systems, in different countries and with different conditions. CCFM allows the identification of the stages and products with the greatest carbon footprint and thus, a better management of the sector from an environmental perspective. The Portuguese cork oak sector is used as an application example of the model. The results obtained showed that the agglomeration industry is the hotspot for the carbon footprint of the cork sector mainly due to the production of the resins that are mixed with the cork granules for the production of agglomerated cork products. The consideration of the biogenic carbon emissions and sequestration of carbon at the forest in the carbon footprint, resulted to a great decrease of the sector's carbon footprint. Future actions for improvement are suggested in order to decrease the carbon footprint of the entire cork sector. It was found that by decreasing by 10% the emission factor of the agglomeration and transformation industries, substituting the transport trucks by more recent ones and by decreasing by 10% the cork products reaching the landfilling end-of-life destinations (while increasing the quantities reaching incineration and recycling), a decrease of the total CF (excluding the biogenic emissions and sequestration) of the entire cork industry by 10% can be achieved. published

The purpose of the present study is to evaluate the environmental impacts deriving from the production of natural cork stoppers in Portugal, in order to identify the most significant stages and processes (hotspots) and to suggest improvement actions and alternative scenarios. Life Cycle Assessment (LCA) methodology is used by applying a cradle-to-bottling approach. This approach includes the stages of forest management (not considered in related LCA studies), cork preparation, natural cork stoppers production, finishing and distribution to the bottling locations. The results show that the forest management stage has the largest contribution to the environmental impact of natural cork stoppers in the majority of the impact categories. More specifically, the greatest influence derives from the operations of pruning and spontaneous vegetation cleaning. Additionally, the preparation stage and the production stage influence two impact categories each, while the finishing stage is the hotspot in one impact category. These contributions are mainly caused by the energy requirements of these stages. The total environmental impacts may be decreased by 3%–65% if maintenance pruning operations are not performed and simultaneously cleaning operations are undertaken by rotary mowers instead of disc harrows in the forest management stage. Changes in the production stage, such as decreasing the transport distance between the preparation and the production factory or the use of a combination of manual and mechanical punching, do not show great influence in the total environmental impact.

The cement industry is one of the most important industries worldwide and the world cement production is projected to grow by 0.8-1.2% per year, reaching between 3700 and 4400 megatonnes in 2050. This industry is facing important challenges in the context of restrained use of raw materials and need of optimization of energy consumption. The aim of this paper is to assess environmental impacts of using wastes as a partial replacement of fossil fuels in a representative cement plant in Southern Europe. Refuse derived fuel and scrap tires were employed as alternative fuels. The environmental profile of the cement manufacturing was presented through a cradle-to-gate life cycle assessment approach based on primary data collected in the plant. The functional unit was 1 tonne of ordinary Portland cement and the impact assessment was based on indicators that comply with the ISO 14040. The impact categories studied were abiotic depletion, acidification, eutrophication, photochemical oxidant formation and global warming. The processes that most contributed to these impact categories were the atmospheric emissions in the kiln, the consumption of fossil fuels, and the consumption of electricity in the mills. (C) 2016 Elsevier Ltd. All rights reserved.

The most common practice for disposal of dead bodies is inhumation in soil, which favours interactions with the surrounding environment and returns nutrients to the life cycle. However, when the burial ground is located where hydrogeological, geological and climatic conditions are not favourable to the process, contamination of soils and groundwater may occur, and decomposition may be inhibited, leading to social, economic and political problems. The most critical parameters when assessing the pollution potential of a burial ground are inhumation depth, geological formation, depth of the water table, density of inhumations, soil type and climate. Considering that, this paper presents an overview of the potential threat that cemeteries can pose, analysing and discussing the influence of the main variables causing environmental impacts and public health risks.

Currently there are several methodologies available for estimating the carbon footprint of products. In this study a comparison has been made between the outcomes and the implications of three different methodologies applied to office paper: (1) the ISO 14040/14044 standards limited to the analysis of greenhouse gas (GHG) emissions and the corresponding impact category global warming; (2) the PAS 2050; and (3) the Confederation of European Paper Industries (CEPI) framework. The carbon footprint of office paper from cradle-to-costumer is 4.64, 4.74 and 4.29 g CO 2 eq per A4 sheet according to, respectively, the ISO 14040/14044 standards, the PAS 2050 and the CEPI framework. The ISO 14040/14044 standard methodology allows the quantification of 98% of the total GHG emissions with the smallest effort in data collection. The major hot spots are the stages of eucalypt pulp and office paper production and chemical and fuel production for all methodologies. General methodologies such as those analysed in this study are not enough for the comparison of products. More specific rules, such as Product Category Rules, that limit the degree of freedom in the choice of the functional unit, system boundary, allocation rules, data quality, between others, should be developed.

This paper presents the application of the ADM1 model to simulate the dynamic behaviour of an anaerobic reactor treating the condensate effluent (EC) generated in a sulphite pulp mill. The model was implemented in the simulation software AQUASIM ® 2.1d and its predictions were compared to experimental data obtained in lab-scale semi-continuous assays treating the industrial effluent. Sensitivity analysis revealed high influence of kinetic parameters on the process behaviour, which were further estimated: maximum specific uptake rate ( k m = 13.2 d −1 ) and half-saturation constant ( K s = 0.06 kg COD m −3 ). The accuracy of the optimised parameters was assessed against experimental data from a second lab-scale reactor treating EC effluent with an additional carbon source (molasses). It was concluded that the model predicted reasonably the dynamic behaviour of the anaerobic reactor under different loading rates. In addition, simulations successfully predicted a better stability and performance of the process (lower VFA accumulation and higher COD removal and methane production) for the EC treatment when an external carbon source is added to the reactor, specifically at high organic loads (2 kg COD m −3 d −1 or higher). The model was not able to describe adequately the reactor behaviour at high organic loads when molasses was not added, thus application of the model for the anaerobic treatment of EC effluent needs to be further evaluated.

BACKGROUND: The knowledge of the fluid pattern of full-scale anaerobic reactors is of fundamental importance for the optimisation of biological processes. High solids concentrations often lead to inefficient mixing conditions, which may reduce treatment capacity due to heterogeneity within the biomass. RESULTS: The hydrodynamic characteristics of a full-scale anaerobic contact reactor treating evaporator condensate from a sulphite pulp mill were investigated. The methodology applied was based on the residence time distribution (RTD) technique using lithium as a tracer. Different non-ideal hydraulic flow models were tested and the best model fitting RTD data was the Gamma distribution model with by-pass. It was concluded that the full-scale bioreactor presents a good degree of mixing with about 22% of non-effective volume due to the presence of high amounts of inorganic materials. CONCLUSION: As a result of this study it was possible to both improve the full-scale bioreactor performance and decrease the running costs by changes in the plant operation strategies which allowed reduction of the huge amount of inorganic materials contributing to the non-effective volume. The methodology is simple and results from a unique RTD experiment and confirms the importance of considering mixing characteristics when assessing complex full-scale treatment processes. Copyright © 2009 Society of Chemical Industry

There is a great diversity of methods for estimating carbon storage in harvested wood products (HWP) and, therefore, it is extremely important to agree internationally on the methods to be used in national greenhouse gas inventories. This study compares three methods for estimating carbon accumulation in HWP: the method suggested by Winjum et al. (Winjum method), the tier 2 method proposed by the IPCC Good Practice Guidance for Land Use, Land-Use Change and Forestry (GPG LULUCF) (GPG tier 2 method) and a method consistent with GPG LULUCF tier 3 methods (GPG tier 3 method). Carbon accumulation in HWP was estimated for Portugal under three accounting approaches: stock-change, production and atmospheric-flow. The uncertainty in the estimates was also evaluated using Monte Carlo simulation. The estimates of carbon accumulation in HWP obtained with the Winjum method differed substantially from the estimates obtained with the other methods, because this method tends to overestimate carbon accumulation with the stock-change and the production approaches and tends to underestimate carbon accumulation with the atmospheric-flow approach. The estimates of carbon accumulation provided by the GPG methods were similar, but the GPG tier 3 method reported the lowest uncertainties. For the GPG methods, the atmospheric-flow approach produced the largest estimates of carbon accumulation, followed by the production approach and the stock-change approach, by this order. A sensitivity analysis showed that using the “best” available data on production and trade of HWP produces larger estimates of carbon accumulation than using data from the Food and Agriculture Organization.

This study evaluated the technical feasibility of anaerobic co-digestion of three organic solid wastes under mesophilic conditions: organic fraction of municipal solid waste (OFMSW), industrial sludge (IS) and cattle manure (CM). Different proportions of each substrate were used and the results showed that, in general, the increase of OFMSW in the mixture results in higher methane production and volatile solids reduction. However, the co-digestion of OFMSW with another co-substrate, especially with IS, significantly improved the stability and process performance, with an effective decrease on the need for buffer addition. At mesophilic conditions and 5% of total solids (TS) inside the reactor, the optimum mixtures accessed from response surfaces obtained with the application of the mixture design technique were the binary mixture with 77% of OFMSW and 23% of IS for volatile solids reduction (65%) and also a binary mixture with 86% of OFMSW and 14% of IS for methane production (225mCH43tonTVSadded-1). A good agreement was obtained between the response surfaces and experimental results, which allows the establishment of management strategies for handling these organic wastes in future.

A methodology for assessing fossil fuel-related carbon dioxide (CO2) emissions from operations performed in eucalypt and maritime pine stands was developed and applied to Portugal. This methodology includes all the operations carried out during site preparation, stand establishment, stand tending, logging and infrastructure establishment. For the year 2000, CO2 emissions for the entire area of maritime pine and eucalypt stands in Portugal were estimated to be 51 and 67 Gg CO2 year−1, respectively. These results demonstrate the more intensive nature of the management activities used in eucalypt stands, as these stands occupied an area approximately 30% smaller than maritime pine stands and produced only 5% more harvested wood than maritime pine stands. Wood logging accounted for approximately 40% of the total annual CO2 emissions in both stands. The results obtained from a sensitivity analysis suggest that annual CO2 emissions from eucalypt and maritime pine stands could be decreased by nearly 20%...

This study aims to contribute to the ongoing international debate on the choice of approaches and methods to be used for estimating the amount of carbon that has accumulated in harvested wood products (HWP), within the context of national greenhouse gas emission inventories. A method for estimating carbon accumulation in HWP was developed and applied to three accounting approaches currently under discussion, namely: the stock-change approach, the production approach and the atmospheric-flow approach. This method is consistent with tier 3 methods suggested by the Intergovernmental Panel on Climate Change. An estimation of the carbon accumulation in HWP in Portugal for the period 1990–2000 varied between 112 and 1016 Gg C year −1 . The atmospheric-flow approach provided the most favourable results for the whole period, largely because Portugal acted as a net exporter of carbon. The production approach ranked second, because the HWP exported were mainly produced from domestically grown wood. The uncertainty level of the estimates was in general lower than the uncertainty level expected when using a method based on generic default data. In conclusion, a simple method such as the one developed in this study may be used to estimate carbon accumulation in HWP with acceptable uncertainty levels, provided that country-specific data are available.

The authors acknowledge the publisher in granting permission for making post-print version available in open access institutional repository. Marine ecosystems are affected by water pollution originating from coastal catchments. The delivery of water pollutants can be reduced through water pollution abatement as well as water pollution treatment. Hence, sustainable economic development of coastal regions requires balancing of the marginal costs from water pollution abatement and/or treatment and the associated marginal benefits from marine resource appreciation. Water pollution delivery reduction costs are, however, not equal across abatement and treatment options. In this paper, an optimal control approach is developed and applied to explore welfare maximizing rates of water pollution abatement and/or treatment for efficient diffuse source water pollution management in terrestrial-marine systems. For the case of diffuse source dissolved inorganic nitrogen water pollution in the Tully-Murray region, Queensland, Australia, (agricultural) water pollution abatement cost, (wetland) water pollution treatment cost and marine benefit functions are determined to explore welfare maximizing rates of water pollution abatement and/or treatment. Considering partial (wetland) treatment costs and positive water quality improvement benefits, results show that welfare gains can be obtained, primarily, through diffuse source water pollution abatement (improved agricultural management practices) and, to a minor extent, through diffuse source water pollution treatment (wetland restoration).

In recent years, numerous efforts have been made to include water-related issues in life cycle assessment (LCA) methodology. This study provides an overview of existing methods that address green water use in LCA. In this overview, we analyse the main features of existing LCA methods used to examine changes in long-term blue water availability caused by variations in green water flows, particularly with respect to inventory, the characterisation model and characterisation factors. Moreover, we propose a method of assessing impacts on terrestrial green water flows (TGWI) and addressing reductions in surface blue water production (RBWP) caused by reductions in surface runoff due to land-use production systems. Both TGWI and RBWP are analysed, taking into account the green water use/atmosphere and green water use/soil interfaces. In this proposed method, the life cycle inventory (LCI) phase considers the net green water flow that leaves the land-use production system, allowing the study of two alternative reference land uses: 1) quasi-natural forest and 2) grasslands/shrublands. In the life cycle impact assessment (LCIA) phase, regional- and species-specific characterisation factors (CFs) for the amount of green water evaporated or transpired are also proposed. To illustrate the applicability of the proposed method, we employed a case study on Eucalyptus globulus stands (first rotation), located in Portugal. The results show that different impacts on terrestrial green water flows and on surface blue water production are obtained depending on the alternative reference land use. Moreover, the case study shows that the method developed can be a useful tool assisting in improved national E. globulus forest planning.

An Environmental Product Declaration (EPD) provides information on a product's environmental performance along its life cycle. This paper aims to contribute to the development of Product Category Rules (PCR) specific for ceramic bricks in order to support the establishment of a “cradle to grave” EPD. The methodology for developing the PCR takes into account ISO 14025, ISO 21930 and EN 15804, and the environmental profile is based on the Life Cycle Assessment (LCA) methodology. In this context, some core issues like product category definition, impact categories, indicators, cut-off criteria and allocation criteria are addressed. The selected impact categories for this study were: global warming, ozone layer depletion, photochemical oxidation, acidification, eutrophication, depletion of abiotic resources and respiratory inorganics. Indicators of energy and water consumption were also considered, as well as particle emissions to air. The results obtained from an LCA study on ceramic bricks produced in Portugal, to support the development of the PCR, show that the use of different fuels in the brick manufacturing stage has a significant effect in some impact categories. The use of petroleum coke generates higher impacts than natural gas or biomass. In general, the major environmental impacts occur in the brick manufacturing stage, mainly due to fuel usage in the firing operation. Particle emissions to air should be considered as an additional parameter in the EPD, being especially important when solid fuels are used. A sensitivity analysis of the cut-off criteria options was also conducted, which concluded that a 0.5% decrease in mass proved to be adequate for adoption, with a significant reduction in the effort required for data collection.

European pilchard captures constitute an important source of income for the Portuguese fishing sector. This raw material is used for a varied range of final seafood products, such as canning, fresh seafood consumption or bait for other fisheries. The Portuguese purse seining fleet, which concentrates most of the pilchard landings, has recently obtained the Marine Stewardship Council certification scheme, demonstrating the effort of the fleet to comply with sustainable fishing practices. However, this scheme does not consider the human inputs to the fishery, such as fuel consumption or the use of other materials and resources. Consequently, life-cycle methods, such as Life Cycle Assessment (LCA), have arisen to provide a thorough assessment of the environmental profile of fishing fleets. In the current study, LCA is combined with Data Envelopment Analysis (DEA), a management tool, in order to understand the eco-efficiency of the individual vessels that compose this fleet. A 5-step LCA + DEA method, previously used to assess resembling vessel samples, was used to examine the efficiency of 20 purse seiners in the northern Portugal for years 2011 and 2012. Individual Life Cycle Inventories (LCIs) were gathered for each vessel to perform, thereafter, the Life Cycle Impact Assessment (LCIA). DEA matrices were generated based on the LCI in order to obtain the efficiency values for each unit. Finally, based on the efficiency projections provided by the DEA model, a new LCIA was performed for inefficient vessels in order to calculate the potential environmental benefits of operating at higher levels of efficiency. The average efficiency of the fleet in the two different years of assessment was slightly above 60 %. Moreover, individual vessels showed a fairly low standard deviation across the 2 years of assessment, demonstrating that units with higher levels of efficiency tend to maintain these values through the analysed window. In fact, this result, given its strong correlation with fuel use, appears to have relation with the existence of a certain level of “skipper effect”. Important environmental benefits, mainly linked to the optimisation of fuel resources, could be attained if inefficient vessels were to operate efficiently, especially in terms of two main impact categories: climate change and fossil depletion. The results in this study confirm that fishing small-pelagic fish shows low energy intensity as compared to other fisheries. However, despite this worldwide tendency, the use of LCA + DEA confirms that substantial improvements in terms of optimising energy and material inputs, as well as in reducing environmental impacts, can be attained in these fishing fleets.

The environmental sustainability is one of the current priorities of the Portuguese pulp and paper industry. Life Cycle Assessment (LCA) was the methodology chosen to evaluate the sustainability of the printing and writing paper production activity. This paper grade represents about 60% of the total production of paper in Portugal and its production is expected to increase in the near future. The main goal of this study was to assess the potential environmental impacts associated with the entire life cycle of the printing and writing paper produced in Portugal from Eucalyptus globulus pulp and consumed in Germany, in order to identify the processes with the largest environmental impacts. Another goal of this study was to evaluate the effect on the potential environmental impacts of changing the market where the Portuguese printing and writing paper is consumed: German market vs. Portuguese market. The main stages considered in this study were: forestry, pulp production, paper production, paper distribution, and paper final disposal. Transports and production of chemicals, fuels and energy in the grid were also included in these stages. Whenever possible and feasible, average or typical data from industry were collected. The remaining data were obtained from the literature and specialised databases. A quantitative impact assessment was performed for five impact categories: global warming over 100 years, acidification, eutrophication, non-renewable resource depletion and photochemical oxidant formation. In the German market scenario, the paper production stage was a remarkable hot spot for air emissions (non-renewable CO2, NOx and SO2) and for non-renewable energy consumption, and, consequently, for the impact categories that consider these parameters: global warming, acidification and non-renewable resource depletion. These important environmental impacts are due to the energy requirements in the printing and writing paper production process, which are fulfilled by on-site fuel oil burning and consumption of electricity from the national grid, which is mostly based on the use of fossil fuels. The pulp production stage was identified as the largest contributor to water emissions (COD and AOX) and to eutrophication. Considering that energy consumed by the pulp production processes comes from renewable fuels, this stage was also the most contributing to renewable energy consumption. The paper distribution stage showed an important contribution to NOx emissions, which, however, did not result in a major contribution to acidification or eutrophication. The final disposal stage was the main contributor to the photochemical oxidant formation potential due to CH4 emissions from wastepaper landfilling. On the other hand, paper consumption in Portugal was environmentally more favourable than in Germany for the parameters/impact categories where the paper distribution stage has a significant contribution (non-renewable CO2, NOx, non-renewable energy consumption, acidification, eutrophication and non-renewable resource depletion) due to shorter distances needed to deliver paper to the consumers. For the remaining parameters/impact categories, the increase observed in the final disposal stage in the Portuguese market was preponderant, and resulted from the existence of significant differences in the final disposal alternatives in the analysed markets (recycling dominates in Germany, whereas landfilling dominates in Portugal). The pulp and paper production stages were found to be of significance for almost all of the inventory parameters as well as for the impact assessment categories. The paper distribution and the final disposal stages were only of importance for some of the inventory parameters and some of the impact categories. The forestry stage played a minor role in the environmental impacts generated during the paper life cycle. The consumption of paper in Portugal led to a decrease in the environmental burdens of the paper distribution stage, but to an increase in the environmental burdens of the final disposal stage, when compared with the consumption of paper in Germany. This study provides useful information that can assist the pulp and paper industry in the planning of future investments leading to an increase in its sustainability. The results of inventory analysis and impact assessment show the processes that play an important role in each impact category, which allow the industry to improve its environmental performance, making changes not only in the production process itself, but also in the treatment of flue gases and liquid effluents. Besides that concern regarding pollution prevention, other issues with relevance to the context of sustainability, such as the energy consumption, can also be dealt with.

This study is a contribution to the ongoing debate about the selection of the approach for carbon accounting in wood products to be used, in the future, in the national greenhouse gas inventories under the UNFCCC (United Nations Framework Convention on Climate Change). Two accounting approaches are used in this analysis: the stock-change approach and the atmospheric-flow approach. They are applied to the Portuguese Eucalyptus globulus forest sector. To achieve this objective, the fluxes of wood removed from the forest are tracked through its life cycle, which includes products manufacture (mainly pulp and paper), use and final disposal (landfilling, incineration and composting). This study develops a framework to the estimation of carbon sequestration in the forest of E. globulus, a fast growing species, more specifically, in the calculation of the conversion factors such as bark and foliage percentages and densities, used to convert wood volumes into total biomass. A mass balance approach based on real data from mills is also proposed, in order to assess carbon emissions from wood processing. The results show that E. globulus forest sector was a carbon sink, but the magnitude of the carbon sequestration differs substantially depending on the accounting approach used. The contribution of the forest ecosystem was smaller than the aggregated contribution of wood products in use and in landfills (including industrial waste), which reinforces the role that wood products play in national carbon budgets.