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While coal consumption has played an essential role in fueling the industrialization and urbanization of China, it is also responsible for serious atmospheric pollution. Great efforts have been made by Chinese governments to restrict coal consumption in metropolitan areas. Taking Beijing as a case, this paper investigated the dynamics of coal consumption from 1985 to 2017 with regard to quantity, proportion, and sectoral distribution. A structural decomposition analysis model was developed to identify the key driving forces of the quantity decline in coal consumption. Results showed that Beijing has experienced an evident de-coal process with two stages of relative decline (1985–2005) and absolute decline (2005–2017). Coal intensity and final demand composition changes, mainly associated with technological renovation, energy substitution, and adjustment of economic structure, had positive effects on curbing coal consumption. Results obtained in this study could shed light on energy transition in other regions of China, by building a diversified energy portfolio, optimizing regional industrial structure, and improving technology levels of production and consumption systems. Nevertheless, the de-coal process model of Beijing cannot be fully copied to other regions due to its unique political position and developmental stage, and appropriate adjustments based on local circumstances must be made.

Although the concept of damage cost accounting is already well-studied and applied, its application to pollution still lacks of an integrated accounting framework, while the spatial-temporal variability of accounting results has not been fully discussed. To fill this gap, this review frames the existing models and their limitations into static and dynamic categories, outlining the characteristics of different methods, which consider both human and non-human damages caused by pollution. Existing data sources, that could be used for accounting purposes, are detailed. Finally, this work discusses the relevance of spatial scales for the computation process, in order to obtain a more detailed information support for environmental policies for future compensatory actions. Conclusions highlights the need to develop a more comprehensive database of exposure-response relationships and to incorporate system alternatives into models to achieve a more accurate damage assessment.

Integration of renewable energy technologies and buildings is a step toward more energy efficient buildings in China. However, the life-cycle of energy and environmental emissions associated with geothermal resource use in buildings is not well understood. This study quantifies the life-cycle energy consumption and environmental pollutant emissions of geothermal heat pump (GHP) deployment in China using a university building as an example. A process-based hybrid life cycle inventory (LCI) modeling approach was used to enable a comprehensive system boundary for footprint accounting and to provide specific insights for the design and operation of the geothermal technology. The life-cycle energy of the GHP system was 192 TJ, and the life-cycle SO 2 , NO x , and greenhouse gas (GHG) emissions were estimated at 35 metric tons (MT), 45 MT, and 19130 MT CO 2 e. The annual operational energy use of the GHP was 6.2 and 4.1 kWh per square meter floor area for building heating and cooling respectively. This was an energy use reduction of 84% and 83% compared to municipal heating and air conditioner cooling. The energy and GHG payback times of the GHP systems were 0.5 and 0.3 years respectively, and the facility is estimated to be economically cost-effective in 7.4 years.

It has been previously reported that increased expression of coiled‑coil domain containing 34 (CCDC34), a member of the CCDCs family, may promote the proliferation and invasion of bladder cancer cells. However, its role in colorectal cancer (CRC) remains unclear. The present study investigated CCDC34 expression in CRC tissues and determined the association between CCDC34 expression and biological characteristics in patients with CRC. Additionally, the variation of cell activity, apoptosis, invasion and associated mechanisms were evaluated following CCDC34 inhibition in SW620 cells with small interfering RNA (siRNA). The role of CCDC34 in CRC growth, apoptosis and invasion was investigated. In the current study, immunohistochemistry revealed an overexpression of CCDC34 in CRC tissues compared with paracancerous tissue (χ2=29.810; P

The cubic Ca/Ta-substituted Li6.55(La2.95Ca0.05)(Zr1.5Ta0.5)O12 (LLCZTO) electrolytes were synthesized at 800 °C with Li3BO3 as additives. The optimal amount of Li3BO3 and its influences on the microstructure, crystal structures, Li+ conductivity and the stability of the Li6.55(La2.95Ca0.05)(Zr1.5Ta0.5)O12 were studied by SEM, XRD and EIS. Among all the samples, when the molar ratio of Li3BO3 to the Li6.55(La2.95Ca0.05)(Zr1.5Ta0.5)O12 is 4:5, the highest Li+ conductivity of 1.33 × 10−4 S cm−1 at 30 °C is obtained. When the LLCZTO samples are exposed in air, the Li+ conductivity is deteriorated possibly owing to the side reactions between the LLCZTO and the H2O or CO2 in the air. The Li3BO3 addition can alleviate such deterioration of the Li+ conductivity.

The effort on electrochemical reduction of CO2 to useful chemicals using the renewable energy to drive the process is growing fast recently. In this review, we introduce the recent progresses on the electrochemical reduction of CO2 in solid oxide electrolysis cells (SOECs). At high temperature, only CO is produced with high current densities and Faradic efficiency while the reactor is complicated and a better sealing technique is urgently needed. The typical electrolytes such as zirconia-based oxides, ceria-based oxides and lanthanum gallates-based oxides, anodes and cathodes are introduced in this review, and the cathode materials, such as conventional metal–ceramics (cermets), mixed ionic and electronic conductors (MIECs) are discussed in detail. In the future, to gain more value-added products, the electrolyte, cathode and anode materials should be developed to allow SOECs to be operated at temperature range of 573–873 K. At those temperatures, SOECs may combine the advantages of the low temperature system and the high temperature system to produce various products with high current densities.

In this study, we investigated whether wood pellets were more sustainable than coal for heating buildings in China by presenting a “fuel-to-heat” energy, environmental and economic comparison for both energy sources. Pellet and coal heating systems were modeled using a process-based life cycle inventory modeling approach, and the energy consumption and air pollutant emissions were calculated in Gigajoules (GJ). Wood pellets were also analyzed for their costs and market competitiveness against coal and other fossil fuel heating alternatives. The results showed that the energy saving potential from using pellets instead of coal was 1382 MJ for every 1-GJ of heat generated. Greenhouse gas emissions from pellets were 11.76 kg CO 2 -eq GJ −1 heat, which were approximately 94% less than emissions from coal heating systems. Also, the wood pellet systems reduced SO 2 , NO x and PM emissions by 86%, 56% and 33%. However, the cost of pellets is significantly higher than the cost for coal, and is the primary impediment for the transition from coal to pellets in China. In addition, multiple consumers of wood residue, unstable heat values of pellet, limited supplies, and the lack of product and heating equipment standards also render the transition from coal to pellets impractical.

The coordinated development of industrialization and the ecological environment is vital to achieve ecological civilization in China. Integratively considering the economy, energy and resources, and environment, this study aims to measure the industrial eco-efficiency of 30 provinces (autonomous regions and municipalities) in China between 2005 and 2013. A three-stage data envelopment analysis (DEA) modeling approach is adopted to eliminate interference of the external environment and statistical noise with industrial eco-efficiency measurement. The results show that regional industrial eco-efficiency in China is affected by the factors of the environmental regulation, technological innovation, level of economic development and industrial structure. After eliminating the impacts of external environment and statistical noise, China's national average industrial eco-efficiency declines by 30%. Between 2005 and 2013, the industrial eco-efficiency of the 30 provinces increases but at different rates of growth. The variation of overall regional industrial eco-efficiency is primarily caused by scale efficiency. Furthermore, all the 30 provinces are classified into four groups to interpret the causes of variation and differences of regional industrial eco-efficiency. In general, the management and technology level and the economy of scale of industries should be improved simultaneously, even though specific opportunities for industrial eco-efficiency improvement vary across provinces in China.

Integrating carbon capture and storage into biomass power plants (BioCCS) can reduce carbon emissions, but its ecological performance associated with natural resources consumption remains unexamined. Taking a typical BioCCS project – the Maowusu biomass direct-fired power plant with the CCS of Spirulina cultivation in Inner Mongolia of China – as a case, this study observed the trade-offs between the carbon reduction benefits and ecological performance of adding CCS to the power plant. Life cycle assessment (LCA) revealed that the combination of CCS avoids 1228 metric tons (MT) of CO 2 emissions annually, while emergy analysis revealed that it deteriorated the ecological performance of the BioCCS system because considerable nonrenewable resources were required by Spirulina cultivation. The BioCCS system is unsustainable in the long run from the ecological point of view. The sensitivity analyses show that there would be no carbon reduction benefits by adding CCS when 60% of designed CO 2 capacity is fixed by Spirulina , and insufficient biomass for electricity generation also affects system performance significantly, which are two main barriers to the BioCCS project. These results indicate that decision-makers should take into account both the carbon reduction benefits and the ecological costs in the development of BioCCS systems.

Emergy analysis can facilitate unified system resources accounting. By combining emergy method with input–output modeling technology, this paper developed an eco-thermodynamic input–output model of the 2007 China economy to account for the sector-specific resource intensities. The results show that the resource intensities for Chinese industry sectors present a distribution with a certain pattern which may vary over three orders of magnitude, measured in terms of resource consumption against economic capital generation. At the scale of the entire economy, the emergy intensities for the resource extraction sectors of non-metallic minerals and metallic ores are the highest. Sectors with the smallest emergy to money ratios are service sectors which rely less on primary natural resources. The sector of coal mining is found to have the largest resource intensity of 6.19E+16 seJ/1E+4 CNY among all sectors, while the sectoral intensity of scrap and waste is only 6.44E+14 seJ/1E+4 CNY, the least one. The insight obtained by juxtaposing resource intensities as well as their structures of industry sectors is useful to identify opportunities for reducing resource intensities that could enable improvements in their ecological sustainability.

A new method for hydrogen separation to acquire high-purity hydrogen using an oxygen-permeable ceramic membrane is proposed and verified in this work. A high hydrogen separation rate of up to 16.3 mL cm−2 min−1 was achieved on an asymmetric dual-phase membrane at 900 °C. No performance degradation was observed in a long-term operation with the feed gas containing 200 ppm H2S.

Biomass power in China is usually regarded as less economically competitive than coal power, partially because the external costs of power generation technologies' effects on human health and the environment are always neglected. To understand the real economic performance of biomass- and coal-fired power in China, a hybrid life cycle inventory modeling approach was developed to estimate the fuel-to-electricity environmental emissions and complete (direct and external) economic costs of the two fuel options. The results show that the direct economic cost of biomass power is 0.44 Chinese yuan (CNY) per kilowatt-hour, about 25%-37% higher than that of coal power. However, because of the significant emissions of greenhouse gas and PM2.5 pollutants during power generation, the external cost of coal-fired power is estimated at 0.17 CNY/kWh on average, substantially higher than that of biomass power (0.06 CNY/kWh). Thus, the economic situations of biomass power reverse when environmental externalities are considered. Specially, wood residue-fired electricity has the lowest complete economic cost (0.48 CNY/kWh), approximately 2%-14% less than that of coal power. Therefore, a reasonable and comprehensive cost accounting mechanism is crucial for the development of the biomass power sector in China. Additionally, win-win policies could be developed to improve the environmental and economic performance of the country's power generation industry.

Directly disrupting the Hsp90-Cdc37 complex can selectively down-regulate kinase clients of Hsp90 and achieve cell cycle arrest., Disrupting the interactions between Hsp90 and Cdc37 is emerging as an alternative and specific way to regulate the Hsp90 chaperone cycle in a manner not involving adenosine triphosphatase inhibition. Here, we identified DDO-5936 as a small-molecule inhibitor of the Hsp90-Cdc37 protein-protein interaction (PPI) in colorectal cancer. DDO-5936 disrupted the Hsp90-Cdc37 PPI both in vitro and in vivo via binding to a previously unknown site on Hsp90 involving Glu47, one of the binding determinants for the Hsp90-Cdc37 PPI, leading to selective down-regulation of Hsp90 kinase clients in HCT116 cells. In addition, inhibition of Hsp90-Cdc37 complex formation by DDO-5936 resulted in a remarkable cyclin-dependent kinase 4 decrease and consequent inhibition of cell proliferation through Cdc37-dependent cell cycle arrest. Together, our results demonstrated DDO-5936 as an identified specific small-molecule inhibitor of the Hsp90-Cdc37 PPI that could be used to comprehensively investigate alternative approaches targeting Hsp90 chaperone cycles for cancer therapy.

Currently, inclinometers are often used to monitor the horizontal displacement of deep foundation pits; however, this method generally has a high cost and complex operation and cannot monitor in real time. In this paper, a novel monitoring method for horizontal displacement of deep foundation pits based on laser image recognition technology is proposed. By identifying the displacement of the spot produced by the laser emitter fixed at the monitoring point, the displacement of the deep foundation pit is determined. In addition, the impact of the angle is considered and eliminated. A series of experimental results indicate that this method exhibits high precision and satisfies the requirements of practical engineering. Simultaneously, it exhibits the advantages of low cost, easy operation, and real-time monitoring. It provides a novel method for the displacement monitoring of deep foundation pits.

There is an increasing need for coastal and marine ecosystems conservation. However, information to guide management decisions for coastal and marine ecosystems is still lacking. Considering the present advantages and limitations of existing ecosystem services valuation (ESV) accounting methods, this paper proposes a detailed donor-side accounting approach, based on emergy method, which could be used as the basis for better policies-making on coastal and marine conservation. In particular, this includes a classification of different ecosystems, a system for ecosystem services (ES) classification, ES formation mechanism, as well as accounting techniques. The ES classification system includes direct, indirect and existence services. Accounting techniques presented here can overcome common limitations in existing accounting methods: (1) double counting; (2) evaluation from the receiver perspective; (3) the inappropriate use and replacement of unit emergy value (UEV). The present method is applied to the evaluation of coastal and marine ecosystems in the Pearl River Delta (PRD), China. Results show that (1) the total coastal ESV decreased from 2000 to 2009 in the PRD area, among which water purification contributes most to the decrease, followed by soil building, climate regulation and microclimate regulation; (2) the coastal ecosystems have the largest potential to regulate climate whether at micro or macro scale; (3) the marine ESV decreased with the ratio of 42.37%, and biomass increase and carbon sequestration account for the decrease; (4) intertidal marshes has the largest ESV per unit area, followed by mangrove, coral reefs and rocky marine shores, while the marine ecosystem has the smallest ESV per unit area. As proved by the case study, this work can provide a basis for an accounting method for coastal and marine ESV assessment, which could serve to improve both the management decision making processes and policy indications through accurately valuing coastal and marine ES, leading to additional investment in conservation of these ecosystems.

Rapid urbanization and population agglomeration in cities result in massive construction and replacement of building stock with unceasing material flows that interact with the environment. The large quantities of material consumption and induced construction and demolition (C&D) waste have already led to severe resource and environmental problems in China. In this study, a system dynamic model under STELLA platform, was developed to simulate the urban residential building flow changes and related steel demand as well as C&D waste generation for the city of Beijing from 1949 to 2100. Results show that the residential building flows and related stocks of Beijing city will largely vary under different scenarios. The baseline scenario witnessed the construction flow peak in 2010 and projects that the building stock will saturate in 2059 with a total building floor area of 8.79E+8 m2, and the largest demolition activity is expected in 2079 with a demolished floor area of 1.65E+7 m2. Overall cyclical dynamics are observed for construction and demolition flows under middle and long-lifetime scenarios, but not prominent for short-lifetime scenarios. If effective urban mining strategies are implemented, up to 70% of future primary steel demand could be satisfied by recycled steel from C&D waste for baseline scenario. The results obtained in this study illustrate the significant resource and environmental saving potential of prolonging the building lifetime and strengthening recycling practices, and highlight the great need of effective policy intervention for waste management infrastructures planning in advance.

The sustainability of producing biodiesel from waste cooking oil (WCO) needs to be thoroughly examined since it is a promising multiple-advantage solution to strengthening energy security, promoting a circular economy, minimizing waste and environmental pollution, and safeguarding food safety. In this study, we employed life cycle assessment (LCA) and life cycle cost (LCC) modeling to evaluate the environmental impacts and economic competitiveness of biodiesel production from WCO in China. The endpoint impacts, including the damage to human health, ecosystem quality, and resource availability, and relevant midpoint impacts were examined. The results show that compared to conventional fossil diesel, the overall endpoint environmental impacts of WCO-based biodiesel are lower, particularly in terms of resource depletion. However, for the midpoint impacts, WCO-based biodiesel has higher impacts on climate change, particulate matter generation, photochemical oxidant formation, human toxicity, and water depletion. The majority of the environmental impacts are due to transesterification, except for water depletion, which is mainly derived from the transportation of the biodiesel fuel. The LCC of the biodiesel is estimated to be 6460 RMB per ton, which is about 31% higher than that of fossil diesel (4921 RMB per ton). The LCC of WCO-based biodiesel is mainly determined by the WCO collection, with a share of 83%. The high purchasing price of WCO feedstock and the fluctuations in international oil prices lead to difficulties in biodiesel industry development. Additionally, the multiple consumers of WCO, the low energy conversion rate, and the immature utilization of the by-products also hinder the massive deployment of WCO-based biodiesel in China.

As China continues to focus on renewable energy in its future development, the energy performance of biofuels has become a hot research topic. However, existing bioenergy assessments have used diverse indexes and inconsistent system boundaries, hindering the comparative analysis of different technologies. Generally, improvements in energy quality (e.g., from solid to gaseous fuel) are accompanied by increases in nonrenewable energy investment. To quantify this trade-off, this study examined the energy return on investment (EROI) of typical biomass conversion systems in China—namely, biomass compression, biodiesel, bioethanol, biogas, biomass gasification, and biomass power generation. Various feedstocks were considered, including first-generation (e.g., corn), second-generation (e.g., corn straw), and third-generation (e.g., algae) feedstock options. The system boundaries of previous biomass footprint calculations are unified to make the results comparable. The results showed that converting raw biomass feedstock to solid fuel had the highest EROI (8.06-24.13), followed by biomass power (2.07-16.48), biogas (1.24-11.05), biodiesel (1.28-2.23), second-generation bioethanol (1.18-9.90), first-generation bioethanol (0.68-3.12), and biomass gasification (1.12-1.57). Compared with fossil fuels (e.g., gasoline, diesel), biofuels had a higher average EROI, indicating obvious energy-saving benefits. Among all biomass conversion pathways, pyrolysis gasification had the highest EROI opportunity cost for both straw and wood residues. This study's findings highlight the need for consistent system boundaries in bioenergy technology deployment to quantify the EROI opportunity cost of each biomass conversion pathway, and recognize the importance of energy efficiency promotion to enhance the economic feasibility of biomass energy industries.

With the great successes in improving rural electrification and reducing poverty, China's small hydropower (SHP) development is expected to provide a good example for other developing countries. However, recently, nearly all new SHP development plans have been halted, and many plants have been urged to shut down or even be removed. The SHP industry in China is now in a dilemma. This paper presents a review of the status of SHP development in China and explores the challenges troubling this industry. It was revealed that SHP resources in many provinces have been intensively exploited, with an exploration rate over 0.80, while untapped resources are primarily located in remote western provinces, such as ecologically fragile Tibet. This intensive and disordered SHP development has caused serious dewatering of rivers and affected local agricultural and household water access, which arouses fierce controversy. Moreover, the role of SHP has been gradually weakened by the extension of power grids and diversified electricity sources. Therefore, the transition and upgrade of the SHP industry has become critical to enhance its sustainable development and to provide a solid example for the world. A divergence management strategy for SHP should be adopted to achieve low-impact development, as opposed to blind large-scale development or rigidly discontinuing all projects. Future transition strategies are proposed in this paper that include delicate management of existing plants and construction of new plants with higher standards, as well as pathways for the development benefits to be shared by a wider range of local residents.

Solar power has been widely treated as renewable and carbon-neutral for being free of fossil resource inputs and causing no carbon emissions. Recent studies, however, qualitatively challenged the traditional thinking derived under a local-realism-based perspective. In response to the recent concerns, this study as a continuation of a previous work offers a systems view into comprehending the ‘renewable’ and ‘carbon-neutral’ characters of solar power by the case of a Chinese pilot solar power plant. Under the systems view, a solar power plant is positioned as an organic system fed by ‘nutrients’ from the macro economy that relies on exogenous non-renewable energy resources as environmental support. A quantitative framework for evaluating the renewability and carbon-neutrality of solar power systems is proposed. A package of indicators is also devised, together with a retrospect of the history of methodological development. The non-renewable energy cost is revealed to be in magnitude 1.6 times as much as the electricity produced and the carbon emissions induced are also shown to be remarkable, implying that solar power is not as renewable and carbon-neutral as generally perceived. In contrast to coal-based power, however, solar power still appears as a promising alternative: the non-renewable energy cost and carbon emission for per unit of electricity delivered are revealed as 55% and 64% of that by the reference coal-fired power generation system in China, respectively. The outcome of this work provides a well-adapted assessment framework and adds insights into the intuitive understanding of renewable-based electricity.

LnFeO3-δ (Ln = La, Pr and Gd) as cathodes for CO2 electroreduction are investigated in solid oxide electrolysis cells at 800 °C. Their surface properties, oxygen desorption behaviour, CO2 adsorption capacity, structure stability under working conditions, activation mechanism and CO2 electroreduction kinetics processes are studied by various characterization methods, such as O2 or CO2 temperature programmed desorption, in situ X-ray diffraction, near ambient pressure X-ray photoelectron spectroscopy, quasi situ infrared spectroscopy and distribution of relaxation time analysis. Similar CO2 electrochemical performances are measured for these Fe-based perovskite cathodes due to their similar physicochemical properties. Although their perovskite structure is stable, cathode surfaces are reconstructed under electroreduction conditions. The produced oxygen vacancies and Fe nanoparticles under the CO2 electroreduction conditions enhance the ability of CO2 adsorption and conversion. Carbonate species are considered as the transition species for CO2 electroreduction based on these characterizations. At last, a mechanism of CO2 electroreduction on these Fe-based perovskite cathodes is proposed.

HSP90-CDC37 protein-protein interaction (PPI) works as a kinase specific-molecular chaperone system to regulate the maturation of kinases. Currently, selectively disrupting HSP90-CDC37 PPI, rather than the direct inhibition of the ATPase function of HSP90, is emerging as a promising strategy for cancer therapy by specifically blocking the maturation of kinases. However, due to the limited understanding of HSP90-CDC37 binding interface, design of small molecule inhibitors targeting HSP90-CDC37 PPI is challenging. In this work, based on the binding mode of compound 11 (previously reported by our group), we discovered a hydrophobic pocket centered on Phe213, which was previously unknown, contributing to the binding affinity of HSP90-CDC37 PPI inhibitors. A series of hydrophobic substituted inhibitors were utilized to confirm the importance of Phe213 hydrophobic core. Finally, we obtained an optimum compound DDO-5994 (exhibited an ideal binding pattern on hydrophobic core) with improved binding affinity (KD = 5.52 μM) and antiproliferative activity (IC50 = 6.34 μM). Both in vitro and in vivo assays confirmed DDO-5994 as a promising inhibitor to exhibit ideal antitumor efficacy through blocking HSP90-CDC37 PPI.

Roadway lighting is critical for creating safe environments for drivers and pedestrians. As China continues to urbanize, the increase in the number of street light facilities will exacerbate the energy and environmental burdens of urban areas. Adopting energy-efficient lighting luminaires and using renewable energy can improve the greenhouse gas (GHG) mitigation potential of urban roadway lighting, contributing to the development of a low-carbon urban environment. In this study, we used a bottom-up approach to estimate GHG mitigation potential associated with replacing current high-pressure sodium (HPS) lamps with light-emitting diode (LED) lamps and deploying solar-wind hybrid street lights, solar street lights, and wind street lights in China. Four classes of urban roads in 662 cities were examined with specific considerations for luminaire specifications, lighting design requirements, and urban-specific availability of solar and wind energy resources. The results showed that the incremental GHG emissions associated with a set of street lights using renewable energy technologies range from 475 to 1631 kg CO2e, yielding a GHG payback time of 1.7-7.7 years, which is environmentally cost-effective. The LED-HPS lamp replacement and renewable energy utilization can annually reduce GHG emissions by 21.2 million tons (Mt) of CO2e, which is dominated by branch (38%) and trunk roads (31%). East China, especially Jiangsu and Shandong provinces, has the largest GHG mitigation potentials. Dalian, Shanghai, and Tianjin are among the top cities with the greatest GHG mitigation potential. For cities with different administrative levels, prefecture-level cities can achieve a GHG mitigation potential of 56%, approximately 11.9 Mt CO2e/year.

Cables as the crucial components, its inspection is the key problem to ensure the safety of cable-stayed bridge. Study of the monitoring methods of cable tension has practical meaning to bridge stability. Firstly, this paper summarized static and dynamic theory of cables. Then, the traditional and innovative monitoring methods of cable force are analyzed, especially the recent emerging intelligent methods. At the end of the paper, a conclusion is provided for the future development of cable-stayed bridges.

Exploring safe and sustainable hydropower, with regard to the size and scheme, is of particular importance to avoid unsettling the fragile ecology in Tibet. Through emergy analysis, this study aimed to assess and compare the environmental performance and sustainability of three different small hydropower (SHP) schemes that are currently in use, i.e., dam-toe, diversion and hybrid, in the Nagqu Prefecture of Tibet. The results indicate that the main difference among the three schemes is the high emergy cost associated with the sizeable dam and related sediment deposition. Correspondingly, the diversion scheme without the dam component is superior to the other two schemes with respect to environmental performance. Considering the necessity of SHP in sparsely populated Tibet, the diversion scheme is recommended more highly than the other two schemes for new SHP plants that are being planned for construction. Because of the much higher resource cost but smaller installed capacity, all three case plants in Tibet present worse performance than their counterparts in Guizhou Province. These results help to encourage China's policy makers to be conservative and proceed with caution regarding SHP development in the fragile Tibetan ecosystem, although SHP has played and will continue to play an essential role in rural electrification in this unique region.

Given the local effects of co-pollutant emissions, the trading of carbon dioxide emissions between facilities to meet global objectives may improve or worsen local air quality and public health. To gear carbon trading toward maximum environmental co-benefits, a quantitative model based on facility-level carbon dioxide emissions, air pollution dispersion and concentration-response functions is proposed and applied to the Beijing-Tianjin-Hebei region to quantify potential changes of local public health caused by carbon dioxide transactions. The results show that the polluters with the highest Population Health Damage Intensity (PHDI) are medium-sized facilities, because larger facilities either employ more effective pollutant control technologies or are located farther away from densely populated areas. Using this modeling framework, key facilities, sectors and regions can be identified for maximizing the environmental co-benefits from introduction of carbon market and avoiding undesirable environmental damage.

Existing policies of household biogas projects focus mainly on supports on construction, but less consider management and maintenance, resulting in high scrap rate and waste of resources. Alternative policies must be explored to balance construction and operation. Taking the costs and benefits from a typical rural household biogas project, this paper assesses the economic performance at three different subsidy levels, i.e., no subsidy, existing standard and positive externality based standard. Furthermore three subsidy alternatives, one-time, annual and combined option are applied to the externality based standard. The results show that household biogas digesters have unsatisfactory economic performance without any subsidy and even in current subsidy policies. Environmental benefits of the digester were estimated as 2732 Chinese Yuan, significantly larger than existing subsidy standard. To keep continuous work during the 20-year lifespans of digesters, the income disparity of farmers among regions must be considered for policy application. With the increasing of labor costs, the ratio of initial subsidies must be reduced. These results provide policy implications to the future development of biogas projects in terms of both their construction and follow-up management, reuse of the abandoned digesters as well as the exploitation of other emerging renewable energy projects.

In this research, an interval-parameter two-stage stochastic programming approach was developed for supporting the identification of low-carbon strategies and the post-earthquake reconstruction in the city of Gugangyuan, Sichuan province of China. The approach can effectively deal with uncertainties that can be expressed as both probability density functions and interval numbers without any distribution information. Also, the approach can provide useful decision alternatives for supporting long-term corrections for any plans associated with carbon dioxide emission limits within a city context. The developed approach was applied in the city of Guangyuan. Three scenarios were established including the baseline (i.e., regional planning) as scenario 1, zero carbon emission as scenario 2, and carbon sink as scenario 3. Also, based on practical information and the collected data, three projection values (i.e., low, medium and high levels) for the carbon emission of the entire city were generated and analyzed under varying probability levels (i.e., 20, 60, and 20%). The results indicated that in order to achieve low-carbon post-earthquake development in the city, the priority areas and industries for carbon emission reduction would be Chaotian (the secondary industry) > Wangcang (the secondary industry) > Lizhou (the secondary industry) = Qingchuan (the tertiary industry) > Cangxi (the secondary industry) = Chaotian (the tertiary industry).

The need for cities to transition towards a more sustainable urban development has become imperative given the combined impact of climate change, global ecological overshoot, and rapid urbanization. The Ecocity has emerged as an urban modernization concept that attempts to reframe urban development for sustainable outcomes, yet there have been several alterations and coining of new terminologies to describe an ecocity, mainly based of concepts and the design methodology and/or the purpose the city is to serve. Even though the eco-city concept and development profess to have some basic principles – dogma – mostly based on urban sustainability, the rapid changes in terminology in recent times calls the attention of many policy makers, investors, development promoters and stakeholders, as well as researchers alike. Beyond these corporate borders, are also the culture (people) and the environment that are influenced by (and interacts with) the eco-city. However, there is no widely accepted framework for assessing Eco-cities. Besides, the methods and outcomes of Eco-cities; and how these outcomes can be evaluated to determine the performance of Eco-cites remain unresolved. This paper presents a framework for assessing the performance of Eco-cities. It argues that due to the inherent differences in the culture, topography, climate, economy, infrastructural base, and technological advancement etc. of cities around the world, Eco-cities may embody distinct characteristics in the way they are understood and applied in different regions. Nonetheless, using a common benchmark across geographical regions, one can do performance assessment of Eco-cities, which can be basis for replication, accessibility, as well as serve as goal metrics.

Landfill odors have created a major concern for the Chinese public. Based on the combination of a first order decay (FOD) model and a ground-level point source Gaussian dispersion model, the impacts from odors emitted from the 1955 landfills in China are evaluated in this paper. Our bottom-up approach uses basic data related to each landfill to achieve a more accurate and comprehensive understanding of impact of landfill odors. Results reveal that the average radius of impact of landfill odors in China is 796 m, while most landfills (46.85%) are within the range of 400-1000 m, in line with the results from previous studies. The total land area impacted by odors has reached 837,476 ha, accounting for 0.09% of China's land territory. Guangdong and Sichuan provinces have the largest land areas impacted by odors, while Tibet Autonomous Region and Tianjin Municipality have the smallest. According to the CALPUFF (California Puff) model and an analysis of social big data, the overall uncertainty of our calculation of the range of odor impacts is roughly -32.88% to 32.67%. This type of study is essential for gaining an accurate and detailed estimation of the affected human population and will prove valuable for addressing the current Not In My Back Yard (NIMBY) challenge in China.

Trichinellosis is caused by Trichinella spiralis (T. spiralis), which is an important public health problem. In this study, a gene encoding a serine protease from adult worms of T. spiralis (Ts-Adsp) was screened from a cDNA library of adult worms and was cloned and expressed in a prokaryotic expression system. The gene Ts-Adsp was subcloned into the eukaryotic expression vector pcDNA3.1(+), which was named pcDNA3.1(+)-Adsp. Previous studies have found that recombinant Ts-Adsp protein (rTs-Adsp) can elicit partial protection against T. spiralis infection in mice. Our aim was to explore the protective effect of combining a DNA vaccine with the rTs-Adsp protein against T. spiralis. One week after the last vaccination, the serum and spleen were obtained. The levels of IgG, IgG1 and IgG2a and cytokine production in serum and spleen cells were analyzed. The results showed that the levels of humoral and cell-mediated immune responses increased in the pcDNA3.1(+)-Adsp/rTs-Adsp group mice and demonstrated that a Th1/Th2 mixed immune response was induced by pcDNA3.1(+)-Adsp/rTs-Adsp after vaccination. Moreover, mice vaccinated with pcDNA3.1(+)-Adsp/rTs-Adsp displayed a 69.50% reduction in muscle larvae burden. This study suggested that mixed immunity could improve the muscle larvae reduction rate.

Along with rapid urbanization and economic development, urban household consumption has experienced a remarkable change, leading to a corresponding increase in direct and indirect carbon emissions. A systematic accounting of household carbon footprints (HCFs) in Beijing during 2002, 2007, and 2012 using a nested input-output model is presented in this paper. The results indicate that the per capita carbon footprint from urban household consumption in Beijing increased from 3054.05 kg in 2002–4611.12 kg in 2012, of which the indirect emissions were the majority. In terms of consumption structure, food, housing, transportation and communication, and education and entertainment were the four dominant sources contributing to the indirect urban HCFs in Beijing. With respect to the source, local Beijing was the largest contributor for itself materials and service provisions in 2002 and 2007, while the domestic source became the largest contributor in 2012, accounting for 55.08% of the total indirect household carbon emissions. Moreover, we also discovered that families with high income level had much higher HCFs compared to those with low income level. Given these considerations, transitions towards low-carbon household consumption are needed so as to provide equality and sustainability.

Colorectal cancer (CRC) is among the leading causes of cancer-related mortality worldwide. Hexavalent chromium [Cr(VI)] is often present in groundwater. Chronic Cr(VI) exposure is suggested to be one of the main factors inducing cancer. However, the correlation between Cr(VI) and CRC remains unclear. In this study, we investigated the role of Cr(VI) in CRC by establishing a mouse CRC model induced by 1, 2-dimethylhydrazine (DMH). The results showed that Cr(VI) increased weight loss in DMH-induced mice and promoted the formation of tumors. Cr(VI) also increased DMH-induced proliferating cell nuclear antigen (PCNA) levels. Investigation of the underlying mechanisms found that Cr(VI) significantly decreased DMH-induced SOD, GSH and CAT levels, while, the MDA level increased. Metagenomic analyses found that the abundance of Firmicutes and Bacteroidetes in the DMH + Cr group was down-regulated. Interestingly, the combination of Cr(VI) and DMH significantly increased the abundance of Verrucomicrobia. At the family and genus levels, families Akkermansiaceae and Saccharimonadaceae and genus Akkermansia were more abundant in the DMH + Cr group, whereas the abundance of short-chain fatty acid (SCFA)-producing bacteria (family Muribaculaceae, family Lachnosipiraceae, genus Lachnospiraceae_NK4A136_group, and genus Roseburia) decreased. These results indicate that Cr(VI) might aggravate CRC by altering the composition of the gut microflora.

Renewable energy technologies are typically material-intensive in terms of the manufacturing and construction of the infrastructure. In particular, wind power needs a huge foundation and three long blades on a high tower to capture and convert wind energy into electricity. Wind power development in China has been soaring, and the sector has inherited regional disparities. Therefore, an analysis of the material efficiency of the country’s wind power infrastructure system in a spatially and temporally explicit manner will contribute to the green transition of wind power in China. In this study, a bottom-up material flow analysis model and efficiency indicators, including the averaged material intensity (AMI) and the material stock efficiency (MSE), are developed using high-resolution material inventory data to quantify the material in-use stock of China’s wind power sector from 1989 to 2018. The results show that the total material stock of China’s wind power sector reached 172.2 Mt by the end of 2018, and the dominant materials were concrete (85.9%) and steel (17.9%). The AMI decreased from 1615 t/MW in 1989 to 736 t/MW in 2018, presenting a notable dematerialization trend, along with a periodic upgrade in wind turbine sizes. The MSE showed significant spatial disparities, ranging from 35 MWh/kg in Gansu to 66 MWh/kg in Fujian in 2018. Strategies to enhance the material efficiency associated with deploying wind power in China include the design and manufacturing of larger wind turbines, balancing the disparity between production and demand, and coordinating policies between central and local governments to reduce curtailment.

A transitional layer is introduced between the La0.75Sr0.25Cr0.5Mn0.5O3-δ˗Gd0.1Ce0.9O1.95 (LSCM-GDC) cathode and the YSZ (8 mol% Y2O3 stabilized ZrO2) electrolyte by a calcining-stripping-calcining method to improve the cell performance for CO2 electroreduction. The effects of second calcination temperature and the LSCM/GDC weight ratio in the transitional layer are investigated to understand the role of the transitional layer. Experimental results reveal that the transitional layer is effective to decrease the cathodic polarization resistance. The cell performance increases with increasing the second calcination temperature in the temperature range of 800–1200 °C, but decreases at a higher second calcination temperature. The optimal performance is achieved at the second calcination temperature of 1200 °C and the LSCM/GDC weight ratio of 1:1 in the transitional layer. The current densities of the optimized cell with a transitional layer are improved by approximately 50% at various applied voltages compared to the cell without the transitional layer. Besides, based on the calculation results of distribution of the relaxation time and the experimental results, the performance improvement is related to the enhancement of the diffusion and exchange processes of the oxygen species at the three phase boundaries after the introduction of the transitional layer.

The application of garnet-type solid electrolytes in all-solid-state Li metal battery is seriously impeded by the lithium dendrite and resultant short-circuit. To explore its growth mechanism, in this work, a special asymmetric cell configuration is designed with a porous Li6.55La2.95Ca0.05Zr1.5Ta0.5O12 (LLCZTO) electrolyte between two mutually perpendicular Li metal strips. Besides the generally perceived lithium dendrite growth through grain boundaries, it is witnessed for the first time that lithium dendrite could also penetrate and break the LLCZTO grains, i.e., intragranular growth. Furthermore, uniform distributed lithium spherical particles, instead of lithium dendrite, are found on the surface of LLCZTO with Au-coating, demonstrating the beneficial effect of Au layer on restraining lithium dendrite growth. These findings shed new light on the growth mechanism and inhibition measures of lithium dendrite and would be helpful for the future research of all-solid-state Li metal battery with garnet-type solid electrolytes.

Despite the total emission control that has been implemented for decades, China is still confronted with insignificant improvement of environmental quality due to ineffective allocation of pollutant emission permits (PEPs). PEPs allocation at industrial level is critical in promoting industrial restructuring and technological innovation and ensuring effective total emission control. In this study, a bidirectional-coupling optimization model (BCOM) is developed by integrating both forward (focusing on environmental benefits) and backward (focusing on economic benefits) optimization. It is applied to a typical region in China for the allocation of SO2 emission permits among eight key industries in 2020. Under the scheme by BCOM, PEPs for the industries of non-metal and agricultural products will increase 11.6% and 9.2% compared with the 2015 level, which implies that these industries should be encouraged for development. PEPs for the other six industries will all decrease, among which the metal industry has the largest emission reduction rate (34.1%). Emission intensity, growth rate of industrial output and industrial profit rate jointly contribute to differentiated PEPs allocation. The provided interval values of PEPs and industrial output allow flexibility for reshaping the industrial structure. The results of the BCOM are also compared with those of other four alternative allocation methods through comprehensive evaluation to illustrate the robustness of the BCOM with regard to compromising fairness and efficiency and achieving both maximum economic and environmental benefits. The proposed approach and empirical results are expected to offer better decision support to reasonable PEPs allocation and emission reduction at industrial level.

Understanding the complexity and sustainability of infrastructure development is crucial for reconciling economic growth, human well-being, and environmental conservation. However, previous studies on infrastructure's material metabolism were mainly conducted on a global or national scale, due largely to lack of more spatially refined data, and thus could not reveal the spatial patterns and dynamics on a city scale. Here, we integrated material flow analysis (MFA) and geographical information system (GIS) data to uncover the spatiotemporal patterns of the material stocks and flows accompanying the infrastructure development at a high spatial resolution for the case of Shanghai, China. From 1980 to 2010, material stocks and waste output flows of Shanghai's infrastructure system exhibited a significant increase from 83 to 561 million metric tons (Mt) and from 2 to 17 Mt, respectively. Input flows peaked in 2005 because of the economic slowdown and stepped-up policies to cool the housing market. Spatially, the center and peri-urban areas were the largest container of material stocks and biggest generator of demolition waste, while suburban areas absorbed 58%-76% of material inputs. Plans to make the city more compact will enhance the service capacity of stocks but may also increase the use of more energy and emissions-intensive construction materials (e.g., steel). Prolonging the service lifetime of infrastructure through proper management and increasing the recycling and reuse rate of demolition waste are also identified as highly efficient strategies.

Alkaline-earth elements (Ca, Sr and Ba) doped LaFeO3-δ-based perovskite oxides are systematically studied to understand how these alkaline-earth elements influence the performance of the parent LaFeO3-δ for CO2 electroreduction. Their crystalline structure, phase stability, sintering property, oxygen desorption, CO2 adsorption, oxygen vacancies and the electron density of Fe cations are studied. Their electrochemical performance for CO2 reduction is evaluated at 800 °C. Distribution of relaxation time analysis of the impedance spectra is conducted to deeply investigate the electrochemical processes occurring on these perovskite cathodes. Our results show that alkaline-earth elements doping improves oxygen desorption and CO2 adsorption ability without phase structure changes. Meanwhile, the oxygen vacancies and the electrons density of Fe under electroreduction conditions are increased by doping alkaline-earth elements. These changes promote the electrochemical processes of CO2 electroreduction. Ca doping leads to performance decaying quickly under high voltages, while Ba doping increases the interface resistance due to the formation of carbonates. Sr is the best choice among the three alkaline-earth elements. The optimal doping amount of Sr is 20% in the La-site. Excessive Sr doping results in the formation of carbonates on the surface, thus hindering the charge transfer and decreasing the number of active sites.

The unprecedented surge in urbanization and population growth rates is generating multiple impacts, affecting food, energy and water (FEW hereafter) demands. Moreover, the adverse effects are extending to climate, as well as to human and ecosystem health. Coordinated efforts are often deemed critical to minimize the trade-offs while maximizing the synergies in the use and the effective analysis of the interlinkages among food, energy, and water within urban ecosystems. Data are collected and transformed into useful information through different indicators, which are often applied to guide several policies in the urban domain. However, their different nature now asks for a critical reanalysis to collate them into different groups, understanding their guiding principles and identifying possible gaps for further policy- and design-oriented studies. This paper reviews the state-of-the-art on existing urban FEW nexus indicators. Indicators were found to belong to four main distinct groups, measuring resource fluxes (52%); quantifying environmental impacts (13%), and efficiency aspects (29%). Results highlight a need to develop new indicators, considering the inclusion of all involved factors within new integrated metrics. However, prior to developing an overall sustainability indicator system is presented, it would be vital to incorporate as many flows as possible to represent the entire urban systems.

Geothermal power has received a great deal of attention in China as the country strives to be less dependent on coal energy and to seek stable and base load renewable power. The country's 13th Five-Year Plan for geothermal energy calls for an additional 500 MW by 2020. To assess whether this ambitious target can be achieved, this paper provides an overview of the environmental and economic performance of geothermal power based on an emergy evaluation and economic analysis of the Yangbajain plant in Tibet, the largest working geothermal power plant in China. The results indicate that the full flow system that the plant currently uses has a much higher production efficiency than the dry steam geothermal power plant in Italy. In addition, the system exhibits a relatively good environmental sustainability compared to other renewable energy generation technologies. However, it is still not economically feasible without government subsidies. Labor is expensive due to the high demand for trained professionals and the harsh working conditions in Tibet. Since China's high-quality geothermal resources are mainly located in Tibet, it would be quite challenging to achieve the ambitious 500 MW target by 2020. However, considering its environmental competitiveness, attractive subsidy policies and support for scientific research to promote technological innovations are proposed in this study to encourage the growth of the geothermal power industry in China, which would provide the country with another valuable alternative to coal.

Africa is experiencing unprecedented economic growth that requires planners to understand the interactions between the social, economic, and ecological systems to ensure its sustainable development. The present paper uses the emergy method to analyse the Rwandan economy from 1975 to 2016. Emergy-based sustainability indicators were used to analyse and compare two distinct periods of economic growth: the pre- and post-Tutsi genocide periods. The results revealed that, by 2016, the total emergy use had increased by approximately 74% of the emergy recorded in 1975. The increase in total emergy use was associated with an increase in imports with contributions from 6.5 to 46.2% and the renewable resource contribution decrease from 93.5 to 53.8%. The emergy analysis, which covered 41 years, categorises Rwanda as a non-renewable resource-poor country. The total emergy use of the pre-genocide period was significantly lower than the post-genocide period. Based on the 2016 emergy self-support of 54% and the emergy sustainability index of 2.52, Rwanda has the highest import dependence compared to other developing countries listed in this paper and tends toward a developed country like Canada, Portugal, and so on. An imperative decision needs to be made in terms of the management of the economic system of Rwanda, as imports are becoming the highest impetus of the Rwandan economy but are also the top major cause of a long-run sustainability downfall. Thus, the present study recommends a scrutinised selection system of imports by increasing raw materials, particularly non-renewable resources, and by subsequently increasing the internal transformation to be exported. This recommendation is also applicable to other developing countries with similar non-renewable resource statuses.

A certain level of horizontal displacement will occur during excavation or subsequent construction of deep foundation pit. If the support is improper and the horizontal displacement of the foundation pit is too large, it will cause collapse and even affect the buildings around the foundation pit, which will endanger people's life and property. Therefore, the horizontal displacement monitoring of deep foundation pit becomes more and more important. At present, the electronic total station is often used to monitor the horizontal displacement of the foundation pit, but this monitoring method is expensive, prone to accidental errors, and can not be used for real-time monitoring. Therefore, a method of monitoring the horizontal displacement of deep foundation pit by using laser projection sensing technique is proposed in this paper. The horizontal displacement of the foundation pit is replaced by the displacement of the laser spot emitted by the laser, and the horizontal displacement of the foundation pit can be obtained by identifying the displacement of the laser spot projected on the screen. A series of experiments show that the accuracy of this monitoring method meets the engineering requirements and greatly reduces the cost, which provides a new technology for the displacement monitoring of deep foundation pit.

Starting with the 11th Five-Year Plan (FYP) and continuing in the 12th FYP, quantitative and binding targets have been set for energy-efficiency improvement in China. Drawing on international experience in burden-sharing on climate change, this paper presents a framework for provincial-level disaggregation of energy-saving targets in China. Based on principles of equity and efficiency, four scenarios have been established by weighting different choice preferences of responsibility, capacity, and potential. In addition, nonlinear and linear allocation models have been developed by considering or ignoring marginal energy-saving cost. When this framework was applied to the disaggregation of the national energy saving target of 16% during the 12th FYP, the results show that the final allocation schemes are largely determined by the policy maker's choice preferences. The extreme reduction target of 37.26% fell to Shanghai under responsibility preferring (RP) using the linear allocation method, while the capability preferring (CP) scenario considering marginal energy-saving cost is the closest to the actual scheme accepted by the 30 provinces. Development of such a framework may serve as a feasible policy instrument to help China achieve its conservation targets in a cost-effective way and in accordance with its regional development strategies.

Approximately half of the global population resides in cities and accounts for over 80% of global carbon emissions. To improve efficiency in carbon emission reduction, and enhance adaptability of cities to climate change, it is essential to undertake accounting of urban carbon cycle. This plays a prominent role in global carbon cycle. An integrated accounting framework for urban carbon cycle was established herein to support uniform accounting and place-specific comparisons, covering natural and artificial carbon cycles, vertical and horizontal carbon flows, carbon storage and fluxes, and carbon inputs and outputs. Guangyuan, a mountainous city in China that was seriously stricken by Wenchuan earthquake in 2008, was chosen as the case to demonstrate the framework and investigate the effects of post-earthquake reconstruction on carbon cycle. The results show: 1) the proposed framework could effectively assess dynamics of carbon cycle under external disturbances, 2) there were abundant vegetation and correspondingly a large natural carbon tank and vertical carbon input, and low industrialization degree and correspondingly small horizontal and vertical carbon outputs in Guangyuan, 3) the post-earthquake reconstruction led to a series of impacts on carbon cycle, from both aspects of amount and structure, and 4) such impacts of post-earthquake construction on artificial carbon cycle were distinct with a tendency toward low-carbon development in Guangyuan. The results were helpful for investigating the effects of natural disturbance and human interference on urban carbon cycle, which in turn could improve the adaptation to climate change.

To gain a better understanding of the options of biomass power generation in China, this study presented an integrated energy, environmental, and economic evaluation for Salix in China, and a typical Salix direct-fired power generation system (SDPGS) in Inner Mongolia was selected for case study. A tiered hybrid life cycle assessment (LCA) model was developed to calculate the “planting-to-wire” (PTW) energy consumption, greenhouse gas (GHG) emissions, and economic cost and profit of the SDPGS, including feedstock cultivation, power plant construction and operation, and on-grid price with/without government subsidies. The results show that the PTW energy consumption and GHG emissions of Salix are 0.8 MJ/kWh and 114 g CO2-eq/kWh, respectively, indicating an energy payback time (EPBT) of 3.2 years. The SDPGS is not economically feasible without government subsidies. The PTW costs are dominated by feedstock cultivation. The energy saving and GHG mitigation benefits are still robust, even when the power plant runs at only 60% design capacity. For future development of biomass power in China, scientific planning is necessary to guarantee a sufficient feedstock supply. In addition, technology progress, mature industrial chains, and reasonable price setting policy are required to enable potential energy and environmental advantages of biomass power moving forward.

To alter the sharply decreasing trend of biodiversity due to human disturbances, much emphasis has been placed on the ecological networks comprised of core areas with high ecological significance and corridors connecting them. The purpose of this paper is to introduce a novel viewpoint and method to identify, analyze and optimize the ecological network of Wuyishan City. The bidirectional least-cost distance model is applied to identify the landscape network in Wuyishan City for the year 1995 and 2005, which can incorportate digraph in ecological network modeling, overcome the limitation of failing to reflect the orientation of the species' dispersal process, and make the process of modeling more convincing by distinguishing flux orientation of “go” and “return” of two random patches. Three new metrics, i.e., network cyclicity, degree of cyclicity, and degree of connectedness, which can quantify the integrity and continuity of network and the relation between network organization and ecological process, are introduced to measure the presence and strength of cyclic pathways in a network and reflect the network's ability to transfer bio-flux. The results show that the ecological network of Wuyishan City in the year 1995 and 2005 have respectively a network size of 18 and 17, degree of connectedness of 1 and 0.7647, network cyclicity of 7.1378 and 8.2570, and degree of cyclicity of 0.3965 and 0.4857, which indicate that the network in Wuyishan City for the year 2005 has strong ability to transfer bio-flux, a high level of eco-process diversity, and a low level of integrity and continuity. It can be concluded that during the past 10 years, different areas of Wuyishan City have gone through landscape degradation and restoration. In the northeast, network components degraded severely and made several patches “isolated islands”, while in the southwest, the network has been developed because of landscape restoration. In particular, the linkages among the patches of natural reserve and its neighborhood increased remarkably, which directly increased the interaction strength and the whole network cyclicity. Then, via scenario analysis, we also identify the patches and linkages that make great contributions to the entire cyclicity and connectedness, such as patches [1,2,3,4,5,6] (Nature reserve and its neighborhood), [12] (bridging the north and west part) and [19] (bridging the south and west part), and linkages among the central patches.

Small hydropower (SHP) in China has experienced soring development in the past two decades and has been assigned ambitious development goals recently, while its environmental performance remains unclear. This study is intended to provide a comprehensive assessment of the environmental impacts of SHP plants in China, to compare the results with its counterparts in other countries, and to identify the key factors in the mitigation of negative consequences. A life cycle assessment of a SHP plant in Guizhou Province of China was conducted in a cradle-to-grave manner following the ISO 14040 guidelines. The functional unit is defined as 1 MWh of net electricity produced by the plant. The CML 2001 method was applied to characterize the environmental impacts. The environmental impact categories considered in this study included global warming (GWP), abiotic depletion (ADP), acidification (AP), freshwater aquatic ecotoxicity (FAETP), human toxicity (HTP), and photochemical ozone creation (POCP). Further contribution analyses and sensitivity analysis was performed to identify the key contributors to each impact category during the life cycle of the plant. For the case plant, the considered impacts are caused primarily by the construction stage. As for the materials and energy inputs, cement, steel, and electricity are the three dominating ones for the overall environmental impacts. Compared with SHP plants in other countries, the plant performs similar to the MW scale plants in Thailand and Japan but worse than the plant in Switzerland. Further comparison of life cycle inventories (LCIs) revealed that the quality of hydro-energy resources and acquisition of indigenous equipment technology is essential to their environmental performance. The results of the sensitivity analysis suggested that the amount of construction materials and energy consumption as well as the plant output influences its environmental performance significantly. The construction stage of the SHP plant is the most important source of environmental impacts. To minimize the impacts of this stage, optimization of the structural design and application of new construction materials and good construction practices is recommended. In addition, determining suitable installed capacity and advancing equipment technologies to ensure the optimal output is also crucial to improve the environmental performance of SHP plants in China, regarding the current serious problem of unstable operation.