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Abstract: A unified process assessment is carried out to integrate various resources and emissions associated with the life cycle of typical coal-fired power generation systems, based on the thermodynamic concept of exergy as a common objective measure. For a comprehensive assessment of industrial production systems, three indicators termed as ecological efficiency, resources use efficiency and environmental emission intensity are devised to evaluate the overall efficacy. Concretely assessed in the present work are three typical modes of coal-fired power generation systems, i.e., the Average mode that represents the average emissions and efficiency of coal-fired power plants operating in the US in 1999, the New Source Performance Standards (NSPS) mode that meets the New Source Performance Standards, and the low emission boiler system (LEBS) mode as a kind of highly advanced coal-fired power plant utilizing a low emission boiler, as benchmark cases in related NREL (National Renewable Energy Laboratory) report. [Copyright &y& Elsevier]

Abstract: An integrated ecological evaluation of the Beijing economy was presented in the paper based on the emergy accounting with the data in 2004. Through calculating environmental and economic inputs within and outside the Beijing economy, this paper discusses the Beijing’s resource structure, economic situation and trade status based on a series of emergy indicators. Through the comparison of the systematic indicators of Beijing with those of the selected Chinese cities, the general status of the Beijing economy in China is identified. The results also show that most indicators of Beijing are located at middle levels among the selected Chinese cities. Particularly, the environmental impacts, expressed by the ratio of waste to the renewable emergy, and the ratio of waste to the total emergy use, are 84.2 and 0.26, respectively in Beijing in 2004, which indicate that the Beijing economy is greatly reliant on the imported intensive fuels, goods and services with high empower density and environmental loading. [Copyright &y& Elsevier]

Abstract: Based on emergy synthesis, this study presents a comparative study on constructed wetland (CW) and conventional wastewater treatments with three representative cases in Beijing. Accounting the environmental and economic inputs and treated wastewater output based on emergy, different characteristics of two kinds of wastewater treatments are revealed. The results show that CWs are environment-benign, less energy-intensive despite the relatively low ecological waste removal efficiency (EWRE), and less cost in construction, operation and maintenance compared with the conventional wastewater treatment plants. In addition, manifested by the emergy analysis, the cyclic activated sludge system (CASS) has the merit of higher ecological waste elimination efficiency. [Copyright &y& Elsevier]

Abstract: This paper provides an integrated study on the ecological account for the Chinese economy in 2004 based on emergy synthesis theory. The detailed flows of the Chinese economy is diagramed, accounted and analyzed in categories using the biophysically based ecological accounting. Through calculating environmental and economic inputs within and outside the Chinese economy, this paper discusses the Chinese international exchange, describes the resource structure, and assesses its sustainability as a whole. Also, the comparison of systematic indicators, such as emergy/dollar ratio, environmental load ratio, and emergy self-support ratio, with those of the other countries is tabled and explored to illustrate the general status of the Chinese economy in the world. Take, for example, the environmental load ratio, which was 9.29 in China 2004, it reveals that the Chinese economy put high pressure on the local environment compared with those of the environment-benign countries, such as Brazil (0.75), Australia (0.86) and New Zealand (0.81). In addition, in this paper, the accounting method of tourism is adjusted based on the previous researches. [Copyright &y& Elsevier]

Abstract: Presented as a low-carbon building evaluation framework in this paper are detailed carbon emission account procedures for the life cycle of buildings in terms of nine stages as building construction, fitment, outdoor facility construction, transportation, operation, waste treatment, property management, demolition, and disposal for buildings, supported by integrated carbon intensity databases based on multi-scale input–output analysis, essential for low-carbon planning, procurement and supply chain design, and logistics management. [ABSTRACT FROM AUTHOR]

Abstract: For the embodiment of natural resources and environmental emissions in Chinese economy 2005, a biophysical balance modeling is carried out based on an extension of the economic input–output table into an ecological one integrating the economy with its various environmental driving forces. Included resource flows into the primary resource sectors and environmental emission flows from the primary emission sectors belong to seven categories as energy resources in terms of fossil fuels, hydropower and nuclear energy, biomass, and other sources; freshwater resources; greenhouse gas emissions in terms of , , and ; industrial wastes in terms of waste water, waste gas, and waste solid; exergy in terms of fossil fuel resources, biological resources, mineral resources, and environmental resources; solar emergy and cosmic emergy in terms of climate resources, soil, fossil fuels, and minerals. The resulted database for embodiment intensity and sectoral embodiment of natural resources and environmental emissions is of essential implications in context of systems ecology and ecological economics in general and of global climate change in particular. [Copyright &y& Elsevier]

Abstract: An emergy-based comparison analysis is conducted for three typical mega cities in China, i.e., Beijing, Shanghai and Guangzhou, from 1990 to 2005 in four perspectives including emergy intensity, resource structure, environmental pressure and resource use efficiency. A new index of non-renewable emergy/money ratio is established to indicate the utilization efficiency of the non-renewable resources. The results show that for the three mega urban systems, Beijing, Shanghai and Guangzhou, the total emergy inputs were 3.76E+23, 3.54E+23, 2.52E+23sej in 2005, of which 64.88%, 91.45% and 72.28% were imported from the outsides, respectively. As to the indicators of emergy intensity involving the total emergy use, emergy density and emergy use per cap, three cities exhibited similar overall increase trends with annual fluctuations from 1990 to 2005. Shanghai achieved the highest level of economic development and non-renewable resource use efficiency, and meanwhile, lower proportion of renewable resource use and higher environmental pressure compared to those of Beijing and Guangzhou. Guangzhou has long term sustainability considering an amount of local renewable resources used, per capita emergy used, energy consumption per unit GDP and the ratio of waste to renewable emergy. It can be concluded that different emergy-based evaluation results arise from different geographical locations, resources endowments, industrial structures and urban orientations of the concerned mega cities. [Copyright &y& Elsevier]

Abstract: Ecosystem health has been a hot topic of ecosystem management research for years. Considering the urban area as a complex ecosystem consisted of natural, societal and economic entities, urban ecosystem health assessment is necessary to be conducted for the scientific management and proper ecological restoration. Combining with the ecosystem service function of the urban ecosystem, theoretical framework and methodology of the urban ecosystem health assessment based on emergy are proposed and the temporal variation of the health level of the city are also outlined in this paper. Following the principle of ecosystem health assessment, four major factors, including vigor (V), organizational structure (O), resilience (R) and function maintenance (F), are integrated to construct a novel emergy-based urban ecosystem health index (EUEHI). Based on the EUEHI and comparing with those of five other typical Chinese cities, the case study of Baotou city shows that its urban ecosystem health level is steadily arising despite the year 2001 as a turning point. Due to the emphasis on the resource structure adjustment and utilization efficiency, Baotou has obtained a better organizational structure and service function for the total urban ecosystem. [Copyright &y& Elsevier]