Search Results (21)

The objective of this research was to evaluate the sustainability of a co-treatment system that combines Municipal Wastewater (MW) and Acid Mine Drainage (AMD) through the technique of intermittent electrocoagulation, applied as an advanced solution to improve contaminant removal efficiency and optimize energy balance. Four scenarios were analyzed: Treatment I (with a 1/7 ratio of urban wastewater to AMD), Treatment II (which includes an artificial wetland), Treatment IIIa (which introduces electrocoagulation to enhance sulfate removal and pH regulation), and Treatment IIIb (which employs a 1/15 ratio of AMD to eutrophic water). The methodology focused on calculating key sustainability indicators such as the Net Yield Ratio (EYR), Emergy Inversion Ratio (EIR), Environmental Loading Ratio (ELR), and Sustainability Index (SI), in order to assess the impact of each technology on the energy efficiency and environmental load of the system. The results showed that, although Treatment IIIa was effective in contaminant removal, the EIR increased to 0.18 and the ELR rose to 0.62, indicating a higher reliance on non-renewable inputs due to increased energy demand. However, Treatment IIIb, which combines electrocoagulation with eutrophic water, significantly improved the sustainability of the system, achieving an SI of 2.31 and an ELR of 1.22, reflecting a reduction in energy efficiency due to intensive use of external resources, but overall greater sustainability compared to the other scenarios. This research concludes that intermittent electrocoagulation, when integrated with synergistic resources like eutrophic water, can enhance contaminant removal efficiency and improve the use of renewable resources, minimizing environmental load and increasing the sustainability of wastewater treatment systems. Full article

The disturbance in river ecosystems caused by reservoirs and dams has become a critical topic, attracting increasing attention. However, the extent to which reservoir and dam construction and operation impact downstream river ecosystem health and ecosystem service functions is not fully understood. This research examines the Xiaolangdi Reservoir and the Lower Yellow River (LYR) ecosystem in China as a case study. We analyzed the complex material and energy flows in the LYR ecosystem using emergy theory and developed a set of emergy-based indicators for the quantitative assessment of river ecosystem health and services under reservoir operation interference. The results indicate that the total natural capital and environmental endowments of the LYR ecosystem have remained relatively stable after the operation of the Xiaolangdi Reservoir, with an increase in renewable emergy input. The ecosystem’s vigor decreased slightly, while the biomass emergy diversity index remained stable. However, the total emergy inputs increased significantly, with external feedback inputs becoming the most important emergy source for the LYR ecosystem. The resilience of the LYR ecosystem improved, with a significant increase in emergy density and a decrease in the emergy sustainability index. These findings suggest that although the river ecosystem continues to provide supporting services to human society, the extent of these services has diminished compared to pre-perturbation levels. In this research, a methodology for analyzing the impact of key reservoir operations on the ecosystem health and services of a large river is proposed to provide support for large river sustainable development studies. Full article

Sustainable architecture holds research significance as a necessary approach to address climate change. However, the lack of a clear definition and diverse research methods present obstacles in this field. To overcome these challenges, this study adopts an integrated approach that combines ecological and low-carbon aspects and considers the entire life cycle system. The highlight of this article is the integration of two research methods to assess the sustainability of a building system from both ecological and carbon footprint perspectives. This approach has not been extensively explored by researchers thus far. The aim is to quantitatively explore and evaluate the sustainability performance of building systems. The research findings reveal that, among the five life cycle stages, the operational stage of a building exhibits the highest proportions of emergy consumption and carbon emissions, accounting for approximately 89.4% and 90%, respectively. From an emergy analysis perspective, newly constructed building systems demonstrate qualified sustainable parameters (Emergy Sustainability Indicator (ESI) = 2.7 > 1)). However, as the building system ages and operates over time, the overall sustainable parameters gradually decrease, eventually becoming unqualified. Furthermore, carbon emissions analysis indicates that total carbon emissions accelerate with the aging of the building, highlighting the necessity of continuous inputs of material flow, energy flow, and information flow to maintain the building system’s sustainability. The cross-feedback model emerges as the most effective correction method among the input processes, although data collection poses a challenge due to its nonlinearity. This study provides a fresh perspective for architects and building managers, offering insights that contribute to mitigating climate change and promoting sustainable practices in the built environment. Full article

This article examines how circularity can be measured and evaluated in the agricultural sector. Circularity represents a key approach for promoting sustainability in agriculture and for the efficient management of resources. Through a comprehensive review of the scientific literature and employing rigorous selection methods, we identify the relevant indicators and tools for assessing circularity in the agri-food chain. The initial bibliometric analysis was performed by using a Biblioshiny instrument from R package tool Bibliometrics. Additionally, this article analyzes the methodologies based on the indicators and metrics that can be applied to measure the restorative capacity and effectiveness of the agricultural system. Most current research follows the 3R principles of the circular economy and establishes an evaluation index system based on the regional characteristics. Methods such as the multi-criteria decision analysis, data envelopment analysis, and life cycle assessment are the most used to date. For the micro-level analysis, system dynamics, material flow analysis, and emergy analysis were the most suitable. Our results provide a clear perspective on the current state of the research in the field of measuring circularity in agriculture and lay the groundwork for the future development of effective strategies for implementing the circular economy in this crucial sector. Full article

Sustainability studies are vital for the long-term development of ecological cities. For cities, single qualitative or quantitative evaluation studies cannot effectively illustrate the ecological and sustainable status of a city. This study employs the emergy–geographic information system (GIS) method to conduct a sustainability evaluation of a city, so as to effectively verify the evaluation results. The emergy method and GIS are both commonly used approaches to address urban issues, but their synergistic effect has rarely been considered, explored, and utilized in urban planning. This study aims to investigate this effect on Hangzhou city through comparative analysis. The results show that rain (geopotential energy) and rain (chemical potential energy) have the highest emergy values from 2000 to 2035, followed by solar emergy, wind emergy, and geothermal heat emergy. These findings are also supported by the GIS map that shows a similar pattern with renewable emergy. Using the five plots (cropland, woodland, grassland, water area, and built-up land) on the GIS map as examples, the accuracy of emergy calculation results for Hangzhou city can be verified, demonstrating the effectiveness of the emergy–GIS methodology. This research provides practical recommendations for city designers and professionals worldwide on urban sustainability. By incorporating both emergy and GIS methods, cities can make informed decisions toward achieving environmentally sustainable development. Full article

Rivers play a key role in regulating urban ecology, which can improve urban climate while slowing the heat island effect. As one of embodied energy in the field of ecology, emergy theory can be used to quantitatively evaluate the ecological characteristics of a system. This will help to further explore urban ecological sustainability in this article. In this study, four ecological riverbank reconstruction projects have been executed to restore the ecology along the banks of the Jinchuan River in Nanjing, China, which focus on the key river–lakeside and waterfront space in the main urban area. The LCA–emergy–carbon emission method was applied through a series of indicators, including emergy indexes and carbon emission indicators. It is important to distinguish prior research, and few have utilized this approach on urban waterways and waterscapes. The results illustrate that the reconstruction system has obvious improvement significance to the whole river ecology. This change can also be seen when using LCA–emergy analysis. In a 20-year cycle, the emergy of the material production stage and maintenance phase account for a major emergy share, followed by the construction stage, transportation process, and design process stage. The sustainability (ESI indicator) has been improved after carrying out the reconstruction projects. By choosing water and gravel as the primary material, the carbon emission can be reduced. The water treatment process accounts for the vast majority of carbon emissions. Secondly, gravel also plays an important role in carbon emission. Finally, an improved measure (clean energy reuse) was conducted to enhance the ecology of the reconstruction projects and obtained a significant ecological sustainability boost. Full article

Aquaculture is one of the protein production activities with the most significant potential for global development. It is one of the fastest growing in recent years, mainly because of its efficiency in transforming feed into meat. However, the increase in aquaculture production raises some concerns, especially regarding the proper use of natural resources such as water, which is fundamental in aquaculture production systems. On the other hand, numerous systems, models, and production techniques have been developed and used to manage resources and reduce the negative impacts of the activity. However, it is not known which production systems and management practices are more sustainable, although the development and application of these technologies are crucial and profoundly influence this aspect of production. Emergy is a method that considers the contribution of nature and economy in the creation of the product and service, excluding the strictly monetary character present in conventional economic evaluations, being a model used to measure the level of sustainability in productive systems. In this sense, this study characterized the use of emergy analysis in aquaculture systems and discussed the main applications and potential uses, in addition to identifying the importance of water in the production and better destination of this resource for the economic and sustainable development of aquaculture. The systematic review methodology identified 17 articles using emergy analysis to assess environmental, economic, and social sustainability. The production systems evaluated vary between monocultures and polycultures at different production levels (intensive, semi-intensive, extensive). When all these particularities are transformed into the same unit (emjoule or solar joule), it is possible to compare different scenarios. As a primary resource of nature, water deserves more attention in the emergy accounting of aquaculture systems. It was shown the importance of a more detailed water analysis considering its effective use, impact (alteration or variation in its quality), and flow for a correct emergy analysis as a tool to promote the maintenance of the aquaculture activity over the years, which has in the water its most significant wealth. Full article

Cooling towers remove economically or technically unusable heat using considerable amounts of electricity and, in many cases, water. Several approaches, which vary in methodology, scope, and level of detail, are used for environmental evaluations of these cooling systems. Although the chosen approach has a significant impact on decisions made at the plant level, no methodology has yet been standardized for selecting the approach that best serves the objectives of the evaluation. Thus, this paper provides comparison criteria for the systematic selection of suitable evaluation methods for cooling towers and classifies how the methods score in this respect. These criteria, such as ‘life cycle thinking’, ‘inventoried physical quantities’, ‘temporal resolution’, ‘formalization’, and ‘data availability’, are grouped by overall evaluation objectives such as ‘thoroughness’, ‘scientific soundness’, and ‘usability’. Subsequently, these criteria were used to compare material flow analysis, energy analysis, environmental network analysis, life cycle inventory, life cycle assessment, environmental footprint methods, emergy analysis, exergy analysis, and the physical optimum method. In conclusion, material flow analysis is best suited for the analysis of cooling towers when impact assessment is not required; otherwise, life cycle assessment meets most of the defined criteria. Moreover, only exergy-based methods allow for the inclusion of volatile ambient conditions. Full article

Urban sustainability is the comprehensive manifestation of development structures and economic aggregates. The current sustainable evaluation of cities from a single aspect cannot comprehensively reflect urban sustainable development. Based on emergy, this study constructs an assessment method of urban sustainability from development structures and economic aggregates. Jiaxing is the case study explored as the sustainable development model of cities in the Yangtze River Delta (YRD) of China. High sustainability of economic aggregates is found in Jiaxing, which is driven by the growth of green GDP. However, the urban development of Jiaxing primarily depends on the input of ecosystem resources, which hinders the sustainability of development structures within Jiaxing. These findings indicate that economic aggregates drive the development of Jiaxing and that the development structures within Jiaxing are unsustainable, resulting from the low sustainability of the natural subsystem and the economic subsystem. As such, it is proposed that industrial structures, development models, and management policies be adopted within cities in the YRD of China in order to promote sustainable development of cities in the YRD of China. This study, therefore, seeks to provide methodological guidance for urban sustainable evaluation. Full article

Petrochemicals, which convert oil and gas into products such as plastics, are fundamental to modern societies. Chemists recognize their role in designing materials and the adverse effects that these may have on the environment, preventing sustainable development. Several methodological frameworks and sustainability assessment approaches have been developed to evaluate the resources used in the petrochemical sector in terms of environmental costs. Still, there is a need to evaluate these systems in terms of environmental costs deeply. A combination of life cycle assessment and emergy accounting—to assess the environmental support for resource use—is applied in this study of the PET production chain in Europe. The unit emergy values of several intermediates are calculated or updated to facilitate the discernment of the quality of energy used and the processes’ efficiency. Several routes for synthesizing renewable para-xylene and ethylene glycol from biomass are discussed and confronted with the efforts focused on recycling and recovering the final product, providing concurrently a procedure and a valuable data set for future CP actions. The results show that understanding the efficiencies changing across the production chain may help stakeholders decide where and when interventions to promote a circular economy are most effective along a petrochemical production chain. Full article

High raw material prices and rivalry from the food industry have hampered the adoption of renewable resource-based goods. It has necessitated the investigation of cost-cutting strategies such as locating low-cost raw material supplies and adopting cleaner manufacturing processes. Exploiting waste streams as substitute resources for the operations is one low-cost option. The present study evaluates the environmental burden of biopolymer (polyhydroxyalkanoate) production from slaughtering residues. The sustainability of the PHA production process will be assessed utilising the Emergy Accounting methodology. The effect of changing energy resources from business as usual (i.e., electricity mix from the grid and heat provision utilising natural gas) to different renewable energy resources is also evaluated. The emergy intensity for PHA production (seJ/g) shows a minor improvement ranging from 1.5% to 2% by changing only the electricity provision resources. This impact reaches up to 17% when electricity and heat provision resources are replaced with biomass resources. Similarly, the emergy intensity for PHA production using electricity EU27 mix, coal, hydropower, wind power, and biomass is about 5% to 7% lower than the emergy intensity of polyethylene high density (PE-HD). In comparison, its value is up to 21% lower for electricity and heat provision from biomass. Full article

The objective of this paper is to present a review of current research on the valuation of ecosystem services, using emergy evaluation methodology (EME). A bibliometric analysis and a systematic review were carried out between 2000 and 2020, using all of Web of Science database subfields that collected 187 papers, selected through the keywords “emergy” and “ecosystem services”. In the second part of the research, we carried out a new search on Web of Science of the 187 initial articles produced, with the words “valuation” and “economic”, in order to analyze those directly related to the evaluation of ecosystem services. The results showed that the EME method is an effective tool to evaluate ecosystem services, since it relates economic and ecological aspects in the evaluations. The research also indicated that the use of isolated methods does not appear to be the most appropriate solution, and that emergy used in combination with other methodologies can be used to obtain more accurate and comprehensive results to evaluate natural resources. Full article

Ecological compensation has recently gained significant attention as an economic incentive promoting natural resource management. However, there remain several challenges to its application. A key issue is the lack of a method clearly define the standard of ecological compensation. This study established an accounting methodology for the ecological compensation standard for the water-receiving area in an inter-basin water diversion in China. Beijing, a major water-receiving area of the South-to-North Water Diversion Project, was used as an example of the application of this approach. First, the evaluation index of ecosystem service value of the water-receiving area was selected, then, emergy theory was used to calculate the increment of ecological service value based on the characteristics of each indicator. The ecological service value due to the project was calculated to be 3.898 billion RMB, while the willingness-to-pay by the public was estimated at 915 million RMB. Therefore, the increment of ecological service value was the highest standard of compensation, and the public’s willingness-to-pay was the lower limit of ecological compensation. The final compensation standard can be determined through negotiation between suppliers and beneficiaries under the leadership of relevant governments and water-transfer authorities. Thus, this study aimed to provide a scientific basis for the construction of diversified ecological compensation mechanisms and promote sustainable development of the region. Full article

Operationalization of sustainability assessments is necessary to promote the sustainable development of agroecosystems. However, primarily, focus has been on the development of sustainability assessment tools with less attention on whether these are suitable for adoption and implementation in specific areas. This drawback could lead to inappropriate management guidance for agricultural practices. Hence, three extensively used models, i.e., the Driver–Pressure–State–Impact–Response (DPSIR) framework, ecological footprint (EF), and emergy analysis (EMA), were applied to quantify the sustainability performance of the agroecosystems in 27 cities in the Yangtze River Delta Urban Agglomeration (YRDUA), China, in 2016. The models were compared using the Pearson correlation analysis and natural break method, to determine a more adaptive method for agricultural sustainability assessments. The level of agricultural sustainable development of each city varied according to the methodology considered for its calculation. Compared with the EMA model, the DPSIR and EF models showed a better relationship (Pearson correlation coefficient of 0.71). The DPSIR model more accurately represented regional rankings of the agricultural sustainability at the municipality level due to its comprehensive consideration of multiple dimension factors and significance for policy making. However, each methodology has its own contribution depending on the study objectives. Hence, different models should be used for adequate determination of agricultural sustainable development at different regional scales; this would also enable better implementation of agricultural practices as well as policies in any given agricultural area for promoting the sustainable development of agroecosystems. Full article

To improve the sustainable development ability of logistics parks, this study constructs a sustainability evaluation method of logistics parks based on emergy; analyzes the input (energy, land, investment, equipment, information technology, and human resources) and output (income and waste) of logistics parks from the perspective of emergy; studies the characteristics of the emergy flow of logistics parks; and constructs the function, structure, ecological efficiency, and sustainable development indexes of logistics parks. The basic situation, resource efficiency, and environmental friendliness of the logistics parks are comprehensively evaluated from the emergy point of view. On this basis, targeted decision suggestions are provided for the sustainable development of logistics parks. Finally, the feasibility and effectiveness of the method are verified by an example. This study reveals the internal relationship among economic, environmental, and social benefits of logistics parks through emergy and provides theoretical and methodological support for the sustainable development of logistics parks. Full article