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861.
In this paper, we assess the physical dimensions of Uzbekistan's economy during 1992–2011 by using the economy-wide material flow analysis (EW-MFA) method, which is an internationally recognized tool for such assessments. There have been a number of studies using methodological standardization of EW-MFA, but to the best of our knowledge, it has never been used to assess the metabolism of Central Asian economies, especially, in this case, the Republic of Uzbekistan.Our analysis strives to empirically evaluate macroscopic economic activities by considering the accounting of material flows. The material flows data-set comprises of consistent data for domestic extraction, imports, and exports, as well as other derived MFA-based indicators.The derived indicators are internationally compared for further evaluation of national economic development performance in a given period. The indicators of direct material input (DMI) and total material requirements (TMR) showed a slight increase in 1992–2011 with an average annual increase of 2.79% and 2.34%. The trends of TMR, DMI, domestic material consumption (DMC) and material efficiency, which is indicated by GDP/DMI, displayed lower values than other industrialized countries referenced in the international comparison. Although national economic performance data showed particularly remarkable success, indicators measuring material inputs and DMC reveal an insignificant increase during the period of study. During the second decade of study period, relative decoupling has occurred which indicated that the economic indicator (GDP) grows faster than DMC and other macro indicators grow. 相似文献
862.
This paper aims at analysing how secondary materials production and end of life recovery processes are modelled in life cycle-based environmental assessment methods in order to discuss their suitability in product policy-support contexts, with a focus on Sustainable Consumption and Production (SCP) policies. The equations prescribed in three published, widely recognised standards are evaluated. In addition, more recent modelling approaches that have been adopted in the context of two EU product policy initiatives (the Product Environmental Footprint (PEF) and the Resource Efficiency Assessment of Products (REAPro)) are similarly analysed. All of the methods are scrutinised against eight criteria which we deem to be important in product policy-support contexts, including comprehensiveness, accommodation of open-loop and closed-loop product systems, and consideration of recyclability/recoverability rates, to name a few. Based on this analysis, it is suggested that the PEF and REAPro modelling approaches appear to be better suited for use in product policy-support contexts than do the currently widely endorsed methods that we considered. 相似文献
863.
Wastewater treatment practices should pay more attention to their environmental performances due to their resources consumption and emissions’ impact. While reclaimed water reuse seems to have become a promising practice, is it always feasible in any condition? To address this issue, this study carried out an extended emergy evaluation of a holistic wastewater treatment system. On one hand, this method was extended to include the emissions’ impact. On the other hand, this study integrated a wastewater treatment plant, its excess sludge disposal system and treated water disposal system into an integrated wastewater treatment system (IWTS), so as to evaluate its performances more completely. And then several indicators, including cost per unit pollutant eliminated (CUPE), ratio of positive output (RPO), environmental load ratio (ELR), and sustainability index (SI), were proposed for evaluating the performances of an IWTS. Two scenarios (scenario A: wastewater treatment + sludge landfilling + treated water discharges; scenario B: wastewater treatment + sludge landfilling + reclaimed water reuse) for a livestock wastewater treatment plant in Sichuan Agricultural University located in Ya’an City in Southwest China, as cases, were researched. The results show that scenario B has lower positive output efficiency and greater environmental load than scenario A. Meanwhile, the reclaimed water reuse raises cost per unit pollutant eliminated compared with the treated water being discharged directly; emissions’ impact enhances the environmental load of the two scenarios to different degree; emissions’ impact has decisive effect on the sustainability of the two scenarios. These results mean that the reclaimed water reuse should not be advocated in this case. This study provides some policy implications: (1) wastewater treatment process should be comprehensively evaluated from its resources consumption and impact of emissions; (2) reclaimed water reuse should be carefully evaluated from its pros and cons simultaneously; (3) the local conditions should be considered when implementing reclaimed water reuse, such as local water body conditions, market demands, the related laws and regulations, corporations’ economic conditions, etc. 相似文献
864.
在我国经济发展中,地热资源为我国社会经济的发展起到了重要支持作用,地热资源来自于地球内部,其在工业、农业领域中已经成为一种重要的生态型能源。对地热能源的特性及其可持续开发利用模式进行全面的认识,是推动我国经济快速发展与保护自然生态环境的热门课题。鉴于此,本文对地热资源的概念及分类进行探讨,并论述了其主要特性,在此基础上深入解析了地热资源的可持续开发利用模式。 相似文献
865.
Yiqun Chen Fang Yu Shengwen Liang Zongping Wang Zizheng Liu Ya Xiong 《Waste management (New York, N.Y.)》2014,34(11):2014-2021
Three reactors, ordinary, greenhouse, and solar, were constructed and tested to compare their impacts on the composting of municipal sewage sludge. Greenhouse and solar reactors were designed to evaluate the use of solar energy in sludge composting, including their effects on temperature and compost quality. After 40 days of composting, it was found that the solar reactor could provide more stable heat for the composting process. The average temperature of the solar reactor was higher than that of the other two systems, and only the solar reactor could maintain the temperature above 55 °C for more than 3 days. Composting with the solar reactor resulted in 31.3% decrease in the total organic carbon, increased the germination index to 91%, decreased the total nitrogen loss, and produced a good effect on pot experiments. 相似文献
866.
Daijun ZHANG Cui BAI Ting TANG Qing YANG 《Frontiers of Environmental Science & Engineering》2011,5(2):291-297
Shortcut nitrification-denitrification, anaerobic ammonium oxidation (ANAMMOX), and methanogenesis have been successfully coupled in an Expanded Granular Sludge Bed-Biological Aerated Filter (EGSB-BAF) integrated system. As fed different synthetic wastewater with chemical oxygen demand (COD) of 300–1200 mg·L-1 and N H 4 + - N of 30–120 mg·L-1 at the outer recycle ratio of 200%, the influence of influent on ANAMMOX in the integrated system was investigated in this paper. The experimental results showed that higher COD concentration caused an increase in denitrification and methanogenesis but a decrease in ANAMMOX; however, when an influent with the low concentration of COD was used, the opposite changes could be observed. Higher influent N H 4 + - N concentration favored ANAMMOX when the COD concentration of influent was fixed. Therefore, low C O D / N H 4 + - N ratio would decrease competition for nitrite between ANAMMOX and denitrification, which was favorable for reducing the negative effect of organic COD on ANAMMOX. The good performance of the integrated system indicated that the bacterial community of denitrification, ANAMMOX, and methanogenesis could be dynamically maintained in the sludge of EGSB reactor for a certain range of influent. 相似文献
867.
城市下水道污水水质模型的开发与应用 总被引:1,自引:0,他引:1
建立了下水道水质转化概念模型,以ASM3(活性污泥3号模型)为基础开发了下水道污水水质数学模型,通过模拟试验,运用遗传算法和曲线拟合技术进行了模型率定与参数估值.模型经现场试验验证可较好地模拟下水道中的ρ(DO)与ρ(TOC)的变化.应用该模型进行数值模拟,探讨了初始ρ(DO)和水力停留时间(HRT)等可控因素对下水道中微生物作用及有机质降解的影响.结果表明,在下水道中设置曝气点,可提高污水的ρ(DO),能有效地提高微生物增殖速率,强化有机物的生化降解能力. 相似文献
868.
Conservation of carnivores in an increasingly changing environment is greatly helped by understanding the decision-making processes underlying habitat patch choice. Foraging theory may give us insight into spatio-temporal search patterns and consequent foraging decisions that carnivores make in heterogeneous and fluctuating environments. Constraints placed on central-place foragers in particular are likely to influence both foraging decisions and related spatio-temporal movement patterns. We used discrete choice models to investigate the spatio-temporal ranging behaviour of GPS collared female wolverines (Gulo gulo) with dependent cubs in south-central Norway. Activity patterns, home range use and selection for elevation were analyzed in relation to spatial and temporal covariates (daily and seasonal) and related to different foraging behaviours. In spring, wolverines showed restricted movement patterns around rendezvous sites at high elevations by day, whereas during the night animals were active at lower elevations. Over the summer, this daily pattern in intensity of use diminished and their overall selectiveness for elevation decreased as cubs grow more mobile and independent. At the onset of autumn, wolverines showed intensive use of the profitable forest-alpine tundra ecotone. We argue that reproducing wolverines deployed a foraging strategy attuned to altering their movement patterns throughout the summer to address a continuous, but diminishing, trade-off between providing both food and shelter for their offspring. Incorporating spatially and temporally explicit activity patterns and home range use in discrete choice resource selection models thus enhances the understanding of the motives behind wolverine resource utilization in space and time. Such knowledge may provide guidance to managers designing regional-scale zoning, in order to facilitate carnivore recovery and to minimize conflicts with human activities. 相似文献
869.
In this study, the trends in paracetamol poisoning were examined over more than a decade in Cardiff and compared with patterns for other substances taken in overdose. All data concerned patients aged 14 years and over of both genders, who were referred to the Cardiff Poisons Treatment Unit between 1989 and 2002. The Chi-squared test for trend was used. During the 14-year study period, there were 18,834 admissions to the hospital, involving poisoning either with pure paracetamol or paracetamol in combination with other drugs (37%, N = 6975), and the proportion of admissions with paracetamol poisoning increased from 36% in 1989 to 44% in 2002. Paracetamol was the second most common drug associated with admissions related to poisoning to the Cardiff Poisons Treatment Unit (37%), after alcohol (48%). Thus, paracetamol poisoning remains a major public health concern in the UK. 相似文献
870.
We integrate new challenges to thinking about resource markets and sustainable resource use policies in a general framework. The challenges, emerging from six papers that JEEM publishes in a special issue, are (i) demand uncertainty and stockpiling, (ii) international trade and resource dependence, (iii) deforestation, and (iv) intertemporal effects of climate change policies (“Green Paradox”). We discuss new insights and results on these issues by fitting them into the Hotelling model of non-renewable resource depletion. 相似文献