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Abstract: Reservoirs improve human health by providing a steady water supply, alleviate poverty by producing cheap electricity and strengthen regional economies by providing job opportunities. However, present modes of reservoir operation, without environmental flow targets, have caused ecosystem degradation while satisfying human needs. The degraded aquatic ecosystem conditions caused by tremendous dam construction in China propel a shift from an emphasis on human needs to sustainable modes of reservoir operation. In this paper, an optimizing reservoir operation model was developed to assist the decision making process of balancing human needs and ecological targets. The environmental flow regime paradigm and water shortage ratio of social water supply were respectively used to establish downstream lake ecosystem targets and upstream human needs. An Interactive Dynamic Programming (IDP) was developed to optimize the conflicts of human needs and ecosystem targets. A set of scenarios were designed for reservoir operations in the Baiyangdian basin in a normal year (50% percentage), a wet year (25% percentage) and a dry year (75% percentage), which provided a very useful tool for reservoir operations to balance human needs and ecosystem targets. [Copyright &y& Elsevier]

Abstract: Evaluation of the ecosystem health of urban clusters will help to establish effective management that promotes sustainable regional development. The procedure for using emergy synthesis and set pair analysis models (EM-SPA) is established in this paper by combining the emergy synthesis''s ability to reflect health status from biophysical perspective and set pair analysis’ ability to describe extensive relationships among different variables. Based on the EM-SPA model, the relative health levels of different urban clusters and related health characteristics can be analyzed. The health states of three typical Chinese urban clusters, Jing-Jin-Tang, Yangtze River Delta, and Pearl River Delta, were investigated using the model. The results show that the health status of the Pearl River Delta was relatively good, while that of the Yangtze River Delta was poor. The specific health characteristics of three urban clusters were further compared. The management guidelines of the different urban clusters are also suggested. [Copyright &y& Elsevier]

Analyzing the structure and functioning of the urban system revealed ways to optimize its structure by adjusting the relationships among compartments, thereby demonstrating how ecological network analysis can be used in urban system research. Based on the account of the extended exergy utilization in the sector of urban socio-economic system, which is considered as the composition of extraction (Ex), conversion (Co), agriculture (Ag), industry (In), transportation (Tr), tertiary (Te) and households (Do) sectors, an urban ecological network model is constructed to gain insights into the economic processes oriented to sustainable urban development. Taking Beijing city as the case, the network accounting and related ecological evaluation of a practical urban economy are carried out in this study in the light of flux, efficiency, utility and structure analysis. The results showed that a large quantity of energy and resources have to be consumed to maintain the structure and function of a city. The thermodynamic efficiencies of individual sector in Beijing remain at a low level. The social system in Beijing is a highly competitive network, and there are 8 competitive relations and only two mutualistic ones. The Domestic and Agricultural sector are the major controlling factors of the system. Moreover, the assessment results of Beijing are compared with the other three socio-economic systems, Norway, UK and Italy, and the ecological network function and structure comparisons are correspondingly illuminated and discussed. The conclusions indicate that the exergy-based network analysis can be refined to become an integrative tool for evaluation, policy-making and regulation for urban socio-economic system management concerning structure and efficiency at urban levels. [Copyright &y& Elsevier]

In ecological network theory, network efficiency and resilience are two essential but complementary attributes of the network structure, and a balance between these factors is critical for an ecosystem's long-term sustainability. Our paper introduces this method and related concepts into water use systems to provide a new angle for sustainability quantification. In this paper, we investigate the meanings of network efficiency and resilience in the context of sustainable development of water use systems, and define sustainable systems based on the optimal balance between network efficiency and resilience. With the consideration of complex artificial characteristics of water use, we propose an optimal water use network and quantify its flows. By ascendency calculation, the balanced network structure can be determined. We then use the four sub-basins of China's Haihe River as a case study to illustrate how the optimal network can be constructed and how the optimal balance for each scenario can be calculated. The results show that the optimal balance for the sub-basins has ascendency values ranging from 0.5970 to 0.7161. By analyzing the contribution of each water use activity to network's balance structure, the location of the optimal balance in water use systems can be better understood. This research represents the first attempt to explore the balance between a network structure's efficiency and resilience as a way to quantify the sustainability of water use systems, and builds a foundation for future studies on the assessment, regulation, and management of water resources. [Copyright &y& Elsevier]

Efficient urban environmental management methods are of importance, even essential to urban sustainable development. Economic methods have increasingly had advantages over other methods of environmental management during the course of the economic system's transition in China. Therefore, the establishment of an effective urban environment-economic management system is necessary and valuable. This paper primarily studies urban environment-economic management and establishes a framework for an urban environment-economic management system. As an example, we created the environment-economic management system of Xiamen, giving priority to economic methods combined with other management methods. We also investigated some problems probably arising in the application of this management system. Finally, a preliminary benefit analysis of the environment-economic management system of Xiamen was conducted. This new comprehensive framework for an environment-economic management system may be used in other cities in China and other developing countries around the world. [ABSTRACT FROM AUTHOR]

Ecological network analysis (ENA) is introduced in this paper as a promising approach to study water use systems. Information indices from ENA involving total system throughput (TST), ascendency and overhead are calculated here. Two related aspects including organization inherent in system structures and synthesized water use intensity related with sustainable development of water use systems are analyzed. The indices of ascendency and overhead are applied for analyzing and characterizing water use network organization. For comparison of sustainability of water use systems from integrated aspects of environment, society and economy and based on TST, a new indicator termed as total system throughput intensity (TSTI) is constructed incorporating parameters of land, precipitation, population, GDP and environmental flow, which can be used as a measure of sustainability in terms of synthesized water use intensity. The Yellow River Basin in China during 1998–2006 is chosen as the case study and divided into subsystems according to the six river sections as from source to Lanzhou (S1-L1), Lanzhou to Toudaoguai (L1-T), Toudaoguai to Longmen (T-L2), Longmen to Sanmenxia (L2-S2), Sanmenxia to Huayuankou (S2-H) and Huayuankou to the mouth of Bo Sea (H-B). The results show that (i) the organization levels of L1-T and H-B are better than those of S1-L1 and T-L2, with those of L2-S2 and S2-H the worst; (ii) the synthesized water use intensity has been improving, of which T-L2, L2-S2 and S2-H are at the highest levels while H-B the lowest. In addition, the comparison between TSTI and other metrics and the relationship between ascendency and TSTI are discussed, from which the importance of TSTI is reflected and the optimization criterions for sustainable development of six subsystems are derived. It can be concluded that the application of ENA in water use systems can provide new angles for water resource management to address the challenges of assessing and optimizing options to obtain more sustainable water use. [Copyright &y& Elsevier]

Abstract: Sustainable development is of great significance in rural areas of China, which are under coupled pressures of poverty reduction, environmental protection and economic development. In these areas, agriculture is the primary sector in supporting their economies, where a number of the relevant production and processing practices cause many adverse impacts on environment and ecosystem. This poses many challenges for decision makers in formulating sustainable development strategies without invoking potential controversies or objections from the public. In this study, a two-level expert system (TES) for facilitating the investigation of public’s perception towards sustainable development in rural areas was developed. Interactive relationships among objectives of socio-economic development and environmental protection, as well as the related policy implications and public responses, were comprehensively examined and incorporated within TES. A two-level system was particularly adopted for facilitating participation of various stakeholders, including decision makers and farmers. The Yongxin County of the Shanjianghu Region in Jiangxi Province, China was selected to demonstrate the applicability of the developed TES. A series of questionnaire surveys were conducted both for acquiring knowledge about the interrelationships among sustainable development, agricultural production, poverty reduction and environmental protection. Public’s perception towards various system components of rural sustainable development were efficiently acquired and analyzed. The results indicated that sustainable development would be very significant on rural areas in China. Also, public awareness to the concept and profile of rural sustainable development was still at a low level, especially for farmers. The developed TES can be not only used for acquiring knowledge of sustainable development, but also providing basic information for the formulation of relevant policies and strategies in rural areas of China. [Copyright &y& Elsevier]

Abstract: This study presents an ecological analysis of Chinese agriculture for the period from 1980 to 2000, on the basis of Odum''s well-known concept of emergy in ecological economy. Emergy analysis methods are explained, illustrated and used to diagram the agro-ecosystem, to evaluate environmental and economic inputs and harvested yield, and to assess the sustainability of the Chinese agriculture as a whole. Detailed structure of the input/output and system indicators are examined from a historical perspective for the contemporary Chinese agriculture in the latest two decades after China''s Reform and Open in the late 1980s. Temporal variation of indices such as increasing environmental load ratio (ELR), decreasing emergy self-support ratio (ESR) and decreasing emergy yield ratio (EYR) illustrate a weakening sustainability of the Chinese agro-ecosystem characteristic of profound transition from a self-supporting tradition to a modern industry based on non-renewable resource consumption. [Copyright &y& Elsevier]