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1.
Emergy analysis of the urban metabolism of Beijing   总被引:3,自引:0,他引:3  
Cities can be modeled as if they were superorganisms with a range of metabolic processes. Research on this urban metabolism can contribute to solving urban environmental problems by revealing details of the metabolic throughput of the system. A key issue is how to find a common basis for measuring the environmental and economic values. By providing a single unified unit, emergy theory integrates the natural and socioeconomic systems and thoroughly evaluates a system's metabolism. We analyzed Beijing's urban metabolic system using emergy synthesis to evaluate its environmental resources, economy, and environmental and economic relations with the regions outside the city during 14 years of development. We compared Beijing's emergy indices with those of five other Chinese cities and of China as a whole to assess Beijing's relative development status. These indices are the emergy self-support ratio (metabolic dependence), the environmental load ratio (metabolic loading), empower density (metabolic pressure), emergy used per person (metabolic intensity per capita), and the monetary equivalent of emergy (emdollars; metabolic intensity). Based on our emergy analysis, Beijing's socioeconomic system is not self-sufficient, and depends greatly on external environmental resources. Its GDP is supported by a high percentage of emergy purchased from outside the city. During the study period, Beijing's urban system showed an increasing dependence on external resources for its economic development. Beijing's loading and pressure on the ecological environment is continuously increasing, accompanied by continuously increasing human emergy consumption. In the future, it will become increasingly necessary to improve Beijing's metabolic efficiency.  相似文献   

2.
Regarding various energy and materials flowing in the urban ecosystem and the merit of emergy as an embodied energetic equivalent for integrated ecological economic evaluation, an evaluation framework of emergy-based urban ecosystem health indicators (UEHIem) was established in view of five aspects including vigor, structure, resilience, ecosystem service function maintenance and environmental impact to depict the urban ecosystem health states. Further, set pair analysis (SPA) was employed to assess the urban ecosystem health level based on the UEHIem, by which the approximate degree of real index set to the optimal one was defined and evaluated to describe the relative health state of the concerned urban ecosystems. Choosing twenty typical Chinese cities in 2005 as cases, we evaluated and compared their urban ecosystem health levels based on UEHIem and SPA. The results showed that health levels of Xiamen, Qingdao, Shenzhen and Shanghai are pretty well, while those of Wuhan, Harbin, Yinchuan, Beijing and Urumchi are relatively weak. Moreover, the relative health levels were analyzed by SPA to discern the influences of the mentioned five aspects on the UEHIem. It is concluded that emergy synthesis combined with SPA can serve as an effective relative-measure to compare different ecosystem health levels of urban ecosystems.  相似文献   

3.
Guangzhou has ambitions to build itself into a world class metropolis by 2010. Sustainable development is the only way to achieve this magnificent goal. Based on the ecological perspective of sustainable development and the principles of ecosystem integrity, this paper develops an approach for evaluation of sustainable development in Guangzhou between 1986 and 1995. A hierarchical evaluation system of four tiers of sustainability indicators was established. Using the method of fuzzy multistage synthetic evaluation, sustainability development level index, QIx, was calculated for the indicators at the B, C, D, and E tiers. Development stages were identified based on these index values. The coordination degree among the economic, social, and natural subsystems was also computed. Further, an overall sustainability index for each year was computed by combining the development level index and the coordination degree. It was found that the urban ecosystem in Guangzhou had generally become more sustainable, in spite of fluctuations in coordination degree. The development level index of the economic subsystem has surpassed that of social and natural subsystems since 1995. Appropriate measures must be taken to ensure coordinated development among the subsystems for the purpose of sustainable development.  相似文献   

4.
生态经济系统的一种整合评价方法:能值理论与分析方法   总被引:34,自引:4,他引:34  
能值理论与分析方法是目前系统生态学和生态经济学发展的新成果,为复合生态系统开拓了一条定量研究途径,是连接生态学和经济学的桥梁。其理论研究与实践应用具有重要的科学意义和应用意义。文章论述了能值分析理论与分析方法的产生背景、过程、主要的基本概念、特点,指出了其需要解决的问题;并以种植业系统为例,简要介绍了能值分析的基本方法和步骤以及能值指标的计算。  相似文献   

5.
This paper presented a thermodynamic synthesis that involved resource accounting, evaluation and modeling of urban ecosystems based on embodied cosmic exergy (EcE), which redefined embodied exergy with the cosmic microwave background radiation (CMBR) as the reference for solar exergy. In a case study of the Beijing urban ecosystem, the major resources supporting the urban ecosystem, both from free natural resources and from the economy, were accounted for, analyzed and evaluated in the same units, Cosmic Joules (Jc). These indicators revealed the current performance of the Beijing urban ecosystem by considering five aspects of the system: EcE sources, EcE intensity, EcE welfare, environmental impacts and economic efficiency. Moreover, through the combination of the EcE synthesis with a systems dynamics, this research constructed an embodied cosmic exergy-based urban system model (EESM) using Beijing as an example of urban development. The results show that the 10 years from 2010 to 2020 will be very critical for the sustainable development of Beijing because many key factors, such as water resources, wastes and urban assets, might be confronted with great changes during this period. These changes will inevitably transform the urban system not only in its external circumstances but also in its inner structure and may lead to serious consequences. Of all the necessary resources, the most sensitive factor is water supply.  相似文献   

6.
土地生态系统健康研究的主要内容及面临的问题   总被引:8,自引:0,他引:8  
陈美球  刘桃菊  黄靓 《生态环境》2004,13(4):698-701
生态系统健康研究是资源环境可持续利用研究中的一个热点。在归纳土地生态系统具有尺度的宏观性、对象的地域性、空间的开放性和动态性、问题的复杂性等特征的基础上,提出了开展土地生态系统健康研究的内容应包括土地生态系统健康的机理、评价和管理等三个主要方面。结合我国的土地资源状况,指出我国开展土地生态系统健康研究面临着包括人口密度过大,土地资源压力大;我国地域辽阔,气候类型多样,社会经济区域发展不均衡,全国各地土地生态系统的区域分异性很强等主要问题。  相似文献   

7.
流域河口湿地生态健康与湿地发育关系研究   总被引:3,自引:0,他引:3  
河口湿地作为一个独立的"活体",有着其自身的地理发育、成熟和衰老的生长过程。以大洋河河口湿地为例,运用面积积分曲线和分维度指数计算大洋河流域发育阶段及河口湿地生长过程,得出如下结论,(1)在河流流域地貌发育早期,河流底蚀、侧蚀、溯源侵蚀强烈,河流含沙量高,泥沙在河口地区沉降而易形成河口湿地;随着流域地貌发育到壮年期,河流泥沙含量输出稳定,河口湿地面积继续扩张;到流域地貌发育晚期,侵蚀减弱,河流含沙量减少,河口湿地缺乏稳定的泥沙供应,在河湾水动力作用下逐渐萎缩、直至消亡。(2)人类活动直接影响河口湿地环境的物理、化学和生物组份,改变了河口泥沙的输入量及沉积环境,人类活动实际上是直接或间接地缩短了河口湿地的发育时间,加速了其发育进程。(3)针对不同发育阶段的河流,在制定河口湿地保护政策和修复措施时,必须充分考虑其地质历史发育特征,政策的制定要符合其生长规律。  相似文献   

8.
In this paper, emergy accounting (EA) and life cycle assessment (LCA) methods are employed to investigate a typical urban wetland park, the Green Lake Urban Wetland Park (GLUWP) of Beijing, in terms of its environmental and capital inputs, ecosystem services and organic matter yields, environmental support, and sustainability. The LCA method is also used to obtain a quantitative estimation of the environmental impact of discharges during the entire life cycle of the GLUWP. Various emergy-based indices, such as emergy yield ratio (EYR), environmental load ratio (ELR), emergy sustainability index (ESI), net economic benefit (Np), and environmental impacts of process-based LCA, including global warming potential (GWP), eutrophication (EU), nonrenewable resource depletion (RU), energy consumption (EN), acidification potential (AP), photochemical oxidant creation potential (POCP), particulate matter (PM) and wastes (W), are calculated. The results show that the GLUWP has higher proportions of renewable resource input, less pressure on the environment, more environmental support and better ecological and economic benefits, which can be considered as an environment-friendly and long-term sustainable ecological practice, compared with another constructed wetland in Beijing. Meanwhile, the dominant environmental impact is induced by POCP with the construction phase contributing the most on the entire life cycle. It is expected that increasing green area, extensively using environment-friendly materials, optimizing construction techniques and reducing power consumption can promote the sustainability of the GLUWP.  相似文献   

9.
基于能值方法的广东省农业系统分析   总被引:30,自引:1,他引:30  
白瑜  陆宏芳  何江华  任海 《生态环境》2006,15(1):103-108
采用能值理论和方法对广东省农业系统的能值投入结构和产出特征进行分析,以期弥补单纯经济分析中出现的自然环境投入价值缺失的不足,并尝试加入农业基本建设投资和农业保险的计量,完善系统投入结构的能值计算。同时,引入Y*/Y指标使广东省农业系统的生产水平与全球平均水平相比较,以利于评价广东省农业系统的生产力及其发展水平,并为其优化发展提供理论依据和现实指导。研究结果:广东省农业系统2003年的能值投资率(3.12)、环境负载率(1.70)、能值/货币比率(4.26E 12sej.$-1)、净能值产出率(1.25)和Y*/Y(0.96)。上述结果与中国平均水平、中国其他省份以及一些发达国家(如意大利和日本)的相应指标比较,表明广东农业系统发展水平高于全国平均水平,低于发达国家。系统能值投入产出结构分析发现,不可更新的工业辅助能值占系统投入总能值的61.92%。为此,应进一步提高农业的可更新能值投入和优化投入结构。  相似文献   

10.
水电开发对河流生态系统服务功能影响的价值评估初探   总被引:5,自引:1,他引:5  
莫创荣 《生态环境》2006,15(1):89-93
提出了计算“流量”,即计算受水电开发影响的河流生态系统服务功能的价值变化量的评估思路和方法,并以广东省河源市风光水利枢纽工程为案例进行了定量分析。在对河流生态系统服务功能进行分类的基础上,根据河流生态系统服务功能可能受到水电开发影响的现实情况和影响特征,选择适当的生态系统服务功能价值核算的方法和参数,计算受影响的生态系统服务功能的价值变化量。案例研究结果表明,风光水利枢纽工程开发方案引起的河流生态服务功能价值变化的正效益为7 676万元/a,负效益为-3 894万元/a,负效益占到其正效益的一半以上,说明该工程开发对东江河流生态系统的消极负面影响也是不容忽视的,应采取适当的生态补偿措施。  相似文献   

11.
Analysis of the structure and function of urban metabolic systems is an important goal of urban research. We used network pathways and network utility analysis to analyze the basic network structure of the urban metabolic system and the complex ecological relationships within the system, providing a new way to perform such research. Using four Chinese cities as examples, we developed an ecological network model of the urban metabolic system. By using network pathway analysis, we studied the changing relationships between metabolic length and the number of metabolic pathways, and between metabolic length and reachability. Based on the distribution of the number of metabolic pathways, we describe the basic structure and intercompartment relationships of the system. By using the sign distribution in the network utility matrix, we determined the ecological relationships and degree of mutualism between the compartments of the system. The basic components of the system consisted of the internal environment, the external environment, and the agricultural, industrial, and domestic sectors. With increasing metabolic length, the ecological relationships among the components of the system became more diverse, and the numbers of metabolic paths and their reachability improved. Although the basic network structure of the four cities was identical, the mutualism index differed. Beijing's mutualism index was superior to that of Shanghai, and much higher than those of Tianjin and Chongqing. By analyzing the structure and function of the urban metabolic system, we provide suggestions for optimizing the structure and adjusting the relationships, and propose methods for the application of ecological network analysis in future urban system research.  相似文献   

12.
Regular physical activity may be a tool in the prevention of sedentary behaviour, overweight, obesity, and obesity-related diseases and plays a fundamental role in health promotion. Moreover, it helps to educate, to develop tolerance and respect for others, to increase interindividual and international exchange, plays a role in social integration, and contributes to an increase in individual sustainable development (ISD). ISD is an extension of the concept of the sustainable development (SD). Its aim is to promote a long, healthy and autonomous life, in conformity with the physical and social environment and economic needs. ISD implies individual participation in the decision-making process, self-determination and freedom and/or responsibility in making individual choices.  相似文献   

13.
Crucial to the method of emergy synthesis are the main driving emergy flows of the geobiosphere to which all other flows are referenced. They form the baseline for the construction of tables of Unit Emergy Values (UEVs) to be used in emergy evaluations. We provide here an updated calculation of the geobiosphere emergy baseline and UEVs for tidal and geothermal flows. First, we recalculate the flows using more recent values that have resulted from satellite measurements and generally better measurement techniques. Second, we have recalculated these global flows according to their available energy content (exergy) in order to be consistent with Odum's (1996) definition of emergy. Finally, we have reinterpreted the interaction of geothermal energy with biosphere processes thus changing the relationship between geothermal energy and the emergy baseline. In this analysis we also acknowledge the significant uncertainties related to most estimates of global data. In all, these modifications to the methodology have resulted in changes in the transformities for tidal momentum and geothermal energy and a minor change in the emergy baseline from 15.8E24 seJ/J to 15.2E24 seJ/J. As in all fields of science basic constants and standards are not really constant but change according to new knowledge. This is especially true of earth and ecological sciences where a large uncertainty is also to be found. As a consequence, while these are the most updated values today, they may change as better understanding is gained and uncertainties are reduced.  相似文献   

14.
底栖动物在水生生态系统健康评价中的作用分析   总被引:7,自引:0,他引:7  
从生态系统健康的概念入手,通过对生态系统健康评价方法的研究和分析,对底栖动物尤其是大型底柄无脊椎动物在生态系统健康评价中的作用进行了分析和总结.生物监测法和多指标评价法是水生态系统健康评价的主要手段,而利用指示物种、预测模型和底柄生物的完整性指数等多种方法可以对水生态系统健康进行快速和准确的评价.如何完善底栖动物在生态系统健康评价中的作用并综合运用其他评价技术,以及结合评价结果对受损水生态系统进行生态修复和重建将是这一领域未来研究的重点所在.  相似文献   

15.
Selected energy and material resource conversion systems are compared in this paper under an extended LCA point of view. A multi-method multi-scale assessment procedure is applied in order to generate consistent performance indicators based on the same set of input data, to ascertain the existence of constraints or crucial steps characterized by low conversion efficiency and to provide the basis for improvement patterns. Optimizing the performance of a given process requires that many different aspects are taken into account. Some of them, mostly of technical nature, relate to the local scale at which the process occurs. Other technological, economic and environmental aspects are likely to affect the dynamics of the larger space and time scales in which the process is embedded. These spatial and time scale effects require that a careful evaluation of the relation between the process and its surroundings is performed, so that hidden consequences and possible sources of inefficiency and impact are clearly identified. In this paper we analyse and compare selected electricity conversion systems, alternative fuels and biofuels, waste management strategies and finally the time evolution of an urban system, in order to show the importance of a multiple perspective point of view for the proper evaluation of a system's environmental and resource use performance.  相似文献   

16.
生态系统服务价值评估的研究进展   总被引:4,自引:0,他引:4  
虞依娜  彭少麟 《生态环境》2010,19(9):2246-2252
生态系统服务价值评估是当前生态经济学和环境经济学的研究焦点。首先回顾了国内外关于生态系统服务功能的概念和分类的研究;其次根据发展历程分析了国外生态系统服务价值的评估研究;然后从全国、区域以及单个生态系统等方面探讨国内生态系统服务价值评估的研究。最后指出现有生态系统服务价值评估研究中的不足及今后发展方向,以期丰富生态系统服务价值评估理论。  相似文献   

17.
Urban metabolism research faces difficulties defining ecological trophic levels and analyzing relationships among the metabolic system's energy components. Here, we propose a new way to perform such research. By integrating throughflow analysis with ecological network utility analysis, we used network flows to analyze the metabolic system's network structure and the ecological relationships within the system. We developed an ecological network model for the system, and used four Chinese cities as examples of how this approach provides insights into the flows within the system at both high and low levels of detail. Using the weight distribution in the network flow matrix, we determined the structure of the urban energy metabolic system and the trophic levels; using the sign distribution in the network utility matrix, we determined the relationships between each pair of the system's compartments and their degrees of mutualism. The model uses compartments based on 17 sectors (energy exploitation; coal-fired power; heat supply; washed coal; coking; oil refinery; gas generation; coal products; agricultural; industrial; construction; communication, storage, and postal service; wholesale, retail, accommodation, and catering; household; other consuming; recovery; and energy stocks). Analyzing the structure and functioning of the urban energy metabolic system revealed ways to optimize its structure by adjusting the relationships among compartments, thereby demonstrating how ecological network analysis can be used in future urban system research.  相似文献   

18.
太湖不同湖区生态系统健康评价方法研究   总被引:1,自引:0,他引:1  
基于长期的监测资料,计算了表征湖泊生态系统健康的系统能(Ex)、系统能结构(Exst)和生态缓冲容量(|β|)指标,以及湖泊营养状态指数(Its)。结果表明,太湖不同湖区生态系统健康状况差异明显,1998—2001年太湖典型湖区健康状况由好到差的相对顺序为:东太湖、贡湖和湖心区、梅梁湾、五里湖。在此基础上,提出了富营养化浅水湖泊生态系统健康指标阈值和湖泊系统能量健康指数(IEx)及其健康状况分级。经2002、2003年太湖不同湖区实测检验表明,所提出的湖泊系统能量健康指数及其健康状况分级适用于评价太湖不同湖区生态系统健康的区域分异状况。  相似文献   

19.
太湖不同湖区生态系统健康评价方法研究   总被引:7,自引:0,他引:7  
基于长期的监测资料,计算了表征湖泊生态系统健康的系统能(Ex)、系统能结构(Exs1)和生态缓冲容量(|β|)指标,以及湖泊营养状态指数(Its)。结果表明,太湖不同湖区生态系统健康状况差异明显,1998-2001年太湖典型湖区健康状况由好到差的相对顺序为:东太湖、贡湖和湖心区、梅梁湾、五里湖。在此基础上,提出了富营养化浅水湖泊生态系统健康指标阈值和湖泊系统能量健康指数(IEx)及其健康状况分级。经2002、2003年太湖不同湖区实测检验表明,所提出的湖泊系统能量健康指数及其健康状况分级适用于评价太湖不同湖区生态系统健康的区域分异状况。  相似文献   

20.
Biodiesel from non-grain feedstock has been considered as one of the proper substitutes for fossil fuels associated with a series of activities emerging in China in order to meet the resource shortage and develop the energy crops. This paper presents an ecological accounting framework based on embodied energy, emergy, and CO2 emission for the whole production chain of biodiesel made from Jatropha curcas L. (JCL) oil. The energy and materials invested in and CO2 emission from the whole process, including cropping, transportation, extraction, and production, are accounted and calculated. Also, EmCO2, the ratio of real CO2 released to the emergy-based sustainability indicator per joule biodiesel, is proposed in this paper to present a new goal function for low-carbon system optimization. Finally, the results are compared with those of the bioethanol (wheat) production in Henan Province, China, and bioethanol (corn) production in Italy in view of the indices of embodied energy, emergy and CO2 emissions and EmCO2.  相似文献   

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