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• A dam's failure losses and damages was evaluated by emergy-based procedures. • Three categories were considered to quantify losses and damages: (I) suppressed stocks in the mud passage and deposition areas, (II) social disruption, and (III) landscape. • The evaluated damages resulting from the tailings passage and deposition can be allocated on an energy hierarchy diagram to assist their spatial visualization. In 2015, the 'Fundão' dam's failure in Brazil released 44 million m3 of tailings that traveled 670 km in the 'Doce' river watershed crossing 40 municipalities and two states until reaching the Atlantic Ocean. Since then, a public civil action (PCA) is responsible for litigation processes, and recently established a value of US$ 43.8 billion to repair losses and damages, a value that brings doubts about its accuracy in expressing the loses and damages of the disaster. This claims for alternative methods for its monetary quantification than the current tradicional economic ones. Among others biophysical approaches, the emergy accounting appears as a powerful tool due to its donor side perspective that objectively quantifies value and recognizes energy quality. This study aims to use emergy accounting as method to firstly identify and then quantify the impacts of 'Fundão' dam's failure, considering exclusively the negative direct and immediate impacts. Three categories are considered to quantify loses and damages: (I) suppressed stocks in the mud passage and deposition areas (MPDA), (II) social disruption, and (III) changes in landscape. For all the three scenarios of turnover times (Tt), results show that about 98% of total emergy in the suppressed stocks are related to (II) and (III), while only 2% in average is related to (I). This discrepancy highlights the importance of accounting for (II) and (III) since they are often disregarded or not directly considered by traditional economic approaches. From a macroeconomic perspective, the highest total emergy-based dollars (emdollar, EmUS$) found for scenario #3 reached EmUS$ 149.18 billion, a value 3.4 times higher than the US$ 43.8 billion established by PCA. This higher value is equivalent to the annual emergy demanded by the Ecuador economy with 18 million inhabitants. Rather than providing an accurate monetary value for the 'Fundão' disaster repair, this study contributes for the advancement of discussions about using biophysical methods such as emergy accounting that allows tracking all numbers for objective verification as alternative to the traditional economic approaches in quantifying losses and damages of high proportion disasters. [ABSTRACT FROM AUTHOR]

Abstract: The end of the age of cheap oil and global warming are causing worldwide concerns about energy security and climate change mitigation. Recognizing that the continuous growth paradigm will not change at short to medium time periods, alternative energy sources to fossil fuels are being sought, in which a promising source seems to be that obtained from vegetal biomass. Specifically in Brazil, there are Conventional Ethanol Plants (CEP) using sugarcane, but due to the energy versus food debate and an increasing demand for ethanol, cellulosic ethanol produced by Biorefineries seems to be a viable option. The question is whether the Biorefinery is more sustainable than CEP. This work aims to assess the energetic-environmental performance of a Biorefinery scenario in Brazil, comparing its results against CEP and another alternative small-scale system. For this, a multi-criteria approach was considered through the following methodologies: Embodied Energy Analysis, Ecological Rucksack, Emergy Accounting and Gas Emission Inventory. Results show that Biorefinery scenario has better rating than CEP for the most indicators when the functional unit is mass of ethanol produced, but when dealing with overall system performance, the Biorefinery performance worse. Neither the Biorefinery nor CEP was superior for all indicators, showing the existence of a trade-off. On the other hand, the small-scale system suggests being the best alternative if the aim is to get higher energetic-environmental performance. [Copyright &y& Elsevier]

Abstract: Energy from sources alternative to fossil fuels is being studied and interest in energy derived from vegetal biomass is increasing. In Brazil - mainly at Sao Paulo State -, sugarcane ethanol is being intensively produced on large-scales, giving rise to social and environmental concerns about its production. If ethanol production systems are to maintain a balance between economic, social and environmental aspects, a systemic approach needs to be considered in their assessment. Particularly, human needs other than energy must be taken into account. In this sense, the Integrated Food, Energy and Environmental Services Production (IFEES) on small-scale suggests an alternative approach. The aim of this work is to assess, in a multi-criteria way, the energetic-environmental aspects of a common IFEES found in Brazil and compare its indices against large-scale ethanol production. For this, embodied energy analysis, emergy accounting, ecological rucksack and gas emission inventory are used as tools. Results show that IFEES has better overall energetic-environmental indices than large-scale ethanol production. At the same time, IFEES produces several other by-products than just ethanol (i.e. food, forestry products and environmental services), although productivity of large-scale process is 25 times higher than for IFEES, if only ethanol is considered. [Copyright &y& Elsevier]

Humanity's future depends on the preservation of natural ecosystems that supply resources and absorb pollutants. Rural and urban productions are currently based on chemical products made from petroleum, which are responsible for high negative impacts on the Biosphere. In order to prevent those impacts, efficient public policies seeking for sustainable development are necessary. Aiming to assess the load on the environment (considering the gratuitous contributions of natural systems—a donor's perspective) due to human-dominated process, a scientific tool called Emergy Evaluation has been applied in different production systems, including crops and farms. However, there is still a lack of emergy studies in the context of watersheds, probably due to the difficulty of collecting raw data. The present work aims to carry out an assessment of Mogi-Guaçu and Pardo watershed, through the combined use of Emergy Evaluation and Geographical Information System. The agricultural and natural land uses were considered, while urban areas were excluded. Emergy flows (expressed in seJha−1 yr−1) obtained for all agricultural and natural land uses were expanded for the whole watershed and the emergy indices were calculated. The results show that the watershed has: low renewability (%R =32%); low capture of natural resources through high external economic investment (EYR=1.86); low dependence on natural resources (EIR=1.16); and moderate load on the environment (ELR=2.08). Considering a scenario where sugar-cane crops, orchards and pasture areas are converted from conventional to organic management, watershed's emergy performance improved, reaching a new renewability of 38%, but it is still not enough to be considered sustainable. [Copyright &y& Elsevier]

Aquaponics is a food production system that aims higher sustainability by integrating advantages gained from aquaculture and hydroponic production. Aquaponics aims to mimic the biological process that happens in the natural environment in a controlled production system. As it can be applied to small scales, aquaponics is considered an important alternative for urban regions, which have low availability of agricultural land and water resources. Furthermore, the advantage is that it is located close to final consumers. Aquaponics has been labeled as an environmentally friendly food production system, but its demand for energy and materials cast doubt on its sustainability. A systemic understanding of aquaponics production systems is needed to determine the magnitude and balance between its potentialities and constraints, in which emergy synthesis appears as a powerful tool for this purpose. This study applies emergy synthesis to assess the sustainability of two different (scale and marketable products) urban aquaponics farms in Brazil, but differently from other emergy studies, ecosystem services and disservices are included in the analysis as an attempt to represent the system performance holistically. Results show that the type of materials used in aquaponics infrastructures has the highest influence on total emergy demand. Surprisingly, electricity and fish feed showed a low influence on the total emergy, reinforcing the idea that aquaponics systems have a more efficiency feeding management than traditional aquaculture systems. Besides producing vegetables and fish, the inclusion of ecosystem services highlights the importance of aquaponics for educational and tourism purposes. Finally, the obtained indicators from modeling scenarios revealed that replacing the water source and some materials deserves priority attention to increase the sustainability of urban aquaponics farms. [ABSTRACT FROM AUTHOR]