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1.
Input-output mathematics, which allows a modeler to fully consider direct and indirect relationships among conserved flows in a system, has a long history in economics with prominent use dating to Leontief in the 1930s. Nearly all previous industrial applications of input-output analysis have been grounded in the monetary flows of an economy. Here however, because of the central nature of physical flows in the environmental impact of industry, we consider physical flows to be a fundamental component of an industrial economy. Hence, we propose an input-output based approach for modeling physical flows in industry independent of their monetary implications.
In this first part of a two-part article, a framework for using input-output mathematics to model material and energy flows is constructed from a foundation laid by previous research in nutrient and energy cycling in natural ecosystems. The mathematics of input-output flow analysis is presented from an ecological perspective, culminating in two core capabilities: tracing of flows with environs (investigated in this article) and characterizing system behavior with flow metrics (presented in the second article). We assert that environ analysis is an effective means for tracing flows through industrial systems while fully considering direct and indirect flow paths. We explore material flows of aluminum and five other metals in depth using environ analysis in this article.  相似文献   

2.
This article, continuing with the themes of the companion article, expounds the capabilities of input-output techniques as applied to material flows in industrial systems. Material flows are the primary focus because of their role in directly linking natural and industrial systems and thereby being fundamental components of environmental issues in industrial economies. The specific topic in this article concerns several material flow metrics used to characterize system behavior that are derived from the ecological development of input-output techniques; most notable of these metrics are several measures of material cycling and a measure of the number of processes visited by material while in a system. These metrics are shown to be useful in analyzing the state of material flow systems. Further-more, the metrics are shown to be a central link in connecting input-output flow analysis to synthesis (i.e., the process of using measurements of system behavior to design changes to that system). By connecting the flow metrics to both environmental objectives and controllable aspects of flow models, changes to existing flow systems are synthesized to generate improved system behavior. To bring this pair of articles to a close, several limitations of input-output flow analysis are summarized with the goal of stimulating further interest and research.  相似文献   

3.
4.
A method for quantitative evaluation of data quality in regional material flow analysis (MFA) is presented. The principal idea is that data quality is a multidimensional problem that cannot be judged by individual characteristics such as the data source, given that data from official statistics may not be per se of good quality and expert estimations may not be per se of bad quality, respectively. It appears that MFA data are never totally accurate and may have certain defects that impair the quality of the data in more than one dimension. The concept of MFA information defects is introduced, and these information defects are mathematically formalized as functions of data characteristics. They are quantified on a scale from 0 (no information defect) to 1 (maximum information defect). The proposed method is illustrated in a case study on palladium flows in Austria. A quantitative evaluation of data quality provides opportunities for understanding and assessing MFA results, their a priori information basis, their reliability in decision making, and data uncertainties. It is a formal step toward better reproducibility and more transparency in MFA.  相似文献   

5.
近30年内,人们对生态环境中的微量元素硒从各方面进行了深入细致的研究,已从硒的毒害研究逐渐转向硒的营养研究,因而日益受到人们的重视。尤其我国在对克山病与大骨节病病因研究过程中,发现在生态环境中元素硒的缺乏与克山病和大骨节病的发病有密切的关系,硒的分布状况有其独特的分布规律。因此,系统地研究硒的生物地球化学行为是非常必要的。一、自然界的原生硒硒在自然环境中广泛地分布,几乎在地壳上所有物质中均含有不同量的硒,其重量克拉克值为6×10~5%,Goldschmidt 1954年  相似文献   

6.
Restructuring and Health in Canadian Coastal Communities   总被引:1,自引:0,他引:1  
Environmental and socioeconomic restructuring has had profound consequences for coastal communities in Canada. The decline of traditional resource-based industries—fisheries, forestry, and mining—and the emergence of new economic activities, such as tourism and aquaculture, compounded by concurrent shifts in social programs, have affected the health of environments, communities, and people. Drawing on research conducted as part of the interdisciplinary major collaborative research initiative Coasts Under Stress, we examined the implications of interactive restructuring for the health of people and communities on Canada’s east and west coasts. The research is guided by a socioecological framework that identifies the pathways from interactive restructuring through health determinants to health risks and health outcomes. The utility of the proposed framework is exemplified by a specific place-based example in Prince Rupert, British Columbia, and a case-based example from coastal communities in Newfoundland and Labrador. A focus on interactive restructuring draws our attention to the many challenges associated with promoting health in a context of rapid and often accelerating environmental and institutional change that is relevant to other areas and contexts.  相似文献   

7.
戴铁军  赵鑫蕊 《生态学报》2017,37(15):5210-5220
废弃物回收利用在一定程度上对缓解资源和环境危机起到积极的作用,已经成为可持续发展的重要举措,但生产过程中消耗的资源、能源,排放的污染物同样也会对自然环境产生负面影响。为解决此问题,以废纸回收利用体系为例,基于物质流分析方法构建了生态成本核算模型,为废弃物回收利用体系优化提供基础。在对生态成本相关研究归纳总结的基础上,定义了生态成本的概念,界定了生态成本的研究内容,并分析基于物质流核算生态成本的可行性。生态成本是对生态负荷的价值化,主要分为资源耗减成本、污染产生和环境保护成本以及生态环境损害成本3部分。污染产生和环境保护成本可以通过将总成本按比例分配给正、负产品的方式求得,资源耗减成本和环境损害成本借助LIME方法核算,总生态成本是回收利用体系内部各项生态成本的总和。生态成本核算是评价生态负荷的重要手段,在废纸回收利用体系物质流动图的基础上,分析各生产流程生态成本的构成情况。提出的生态成本核算模型不仅适用于废纸回收利用体系,其他废弃物也同样适用。通过生态成本的核算,寻找到对生态环境影响较大的工序、流程,为废弃物回收利用体系经济与环境的双赢提供理论与实践指导。  相似文献   

8.
The European policy for river management during peak discharge periods is currently changing from exclusion strategies (reinforcement of dykes) to allowing a more natural situation by creating more floodplain space to reduce water levels during peak discharges. In addition, water retention and water storage areas have been created. The new measures are generally being combined with nature development strategies. Up till now, however, ecological targets of broadscale floodplain wetland restoration including sedge marshes, species-rich floodplain forests and carrs, riparian mesotrophic grasslands and other biodiverse riverine ecosystems, have hardly developed in these areas. Most studies on the conditions needed for sustainable ecological development of floodplains have focused on hydrological and geomorphological rather than biogeochemical issues (including nutrient availability and limitation). There are, however, large differences in the composition of river water and groundwater and in sediment quality between rivers in densely populated areas and those in more pristine areas, which serve as a reference. It is very likely that these factors, in combination with heavily altered hydrological regimes and the narrow areas confined between the dykes on both sides of the rivers, impose major constraints on sustainable ecological development of riverine areas. Another issue is that existing wetlands are generally considered to be very appropriate for water retention and conservation, although recent research has shown that this may pose a serious threat to their biodiversity. The present paper reviews the biogeochemical constraints on the combination of floodplain rehabilitation, water conservation and the conservation and development of wetlands. It is concluded that biogeochemical problems (mainly related to eutrophication) predominantly arise in less dynamic parts of the river system, to which the flood-pulse concept applies less. Sound knowledge of the biogeochemical processes involved will contribute to greater efficiency and a better prediction of the opportunities for restoration and development of riverine wetlands. This information can be directly applied in nature management, water management, policy-making and consultancy.  相似文献   

9.
10.
Material flow analysis is a tool that is increasingly used as a foundation for resource management and environmental protection. This tool is primarily applied in a static manner to individual years, ignoring the impact of time on the material budgets. In this study, a detailed multiyear model of the Austrian phosphorus budget covering the period 1990–2011 was built to investigate its behavior over time and test the hypothesis that a multiyear approach can also contribute to the improvement of static budgets. Further, a novel method was applied to investigate the quality and characteristics of the data and quantify the uncertainty. The degree of change between the budgets was assessed and showed that approximately half of the flows have changed significantly and, at times, abruptly since 1990, but it is not possible to distinguish unequivocally between constant and moderately changing flows given their uncertainty. The study reveals that the phosphorus transported in waste flows has increased more rapidly than its recovery, which accounted for 55% to 60% of the total waste phosphorus in 1990 and only 40% in 2011. The loss ratio in landfills and cement kilns has oscillated in the range of 40% to 50%. From a methodological point of view, the multiyear approach has broadened the conceptual model of the budget, making it more suitable as a basis for material accounting and monitoring. Moreover, the analysis of the data reconciliation process over a long period of time proved to be a useful tool for identifying systematic errors in the model.  相似文献   

11.
傅银银  袁增伟  武慧君  张玲 《生态学报》2012,32(5):1578-1586
氮、磷等营养物质过量输入是造成我国湖泊富营养化问题日益严重的根源,磷作为水体富营养化过程关键限制元素,主要来自流域社会经济系统中的人类活动排放,因此,定量刻画社会经济系统内的磷流动路径是追踪水体外源磷来源和进行有效控制磷排放量的前提。以巢湖流域的安徽省含山县为例,构建社会经济系统磷流分析框架,建立磷流核算模型,并在实地调查和数据统计分析的基础上定量刻画了含山县2008年度社会经济系统磷流路径。结果表明,2008年含山县社会经济系统向水体排放的磷总量为1592t,其中农业种植子系统的排放所占比例最大(77%),该子系统的磷利用效率也较低(45%)。因此,含山县富营养化治理的重点是优化农业种植系统的磷流路径,主要措施包括合理施肥、科学排灌等。  相似文献   

12.
Phosphorus (P) is a key factor in aquatic eutrophication, and P contamination has become a common issue worldwide. Many developing countries, including China, have made great efforts in the anti‐P contamination battle. In this article we mainly discuss the P flow in Wuwei, a typical county in China with insufficient wastewater treatment, using the method of static substance flow analysis. We show that characterizing P metabolic pathways and flows at the county level can provide useful information about P pollution. Through complex calculations, we found that Wuwei County released 3,552 metric tons (t) of P into the local aquatic environment in 2008 and that its P load (3.35 kilograms P per capita per year [kg P/cap/yr] or 19.43 kilograms P per hectare per year [kg‐P/ha/yr]) was greater than both the adjoining counties’ and Chaohu City's average levels combined. The agricultural subsystem discharged the largest quantity of P (2,572 t) and had a relatively low production conversion efficiency (32%) and P waste recycling rate (36%). The rural residential and small‐scale livestock breeding systems also accounted for substantial portions of P discharge. Anti‐P contamination efforts should consequently focus on those three subsystems. Based on the results of this case study, we also discuss the feasibility of potential efforts to reduce P contamination.  相似文献   

13.
对内蒙古典型草原不同恢复演替阶段群落土壤养分动态及空间格局、植物养分及其化学计量比时空动态、植物与土壤养分相关性等进行了分析, 以揭示放牧干扰对植物的养分及其化学计量比影响。结果表明: 土壤各养分含量表现为恢复群落略高于严重退化群落, 土壤全氮(STN)/土壤全磷(STP)恢复群落高于严重退化群落, 土壤有机质(SOC)/STN恢复群落低于严重退化群落; 大多数植物叶片C含量在恢复群落最高, 严重退化群落最低, 与恢复演替时间呈正相关, 而植物的全氮(TN)和全磷(TP)含量则是严重退化群落最高, 恢复群落最低, 与退化程度呈正相关, 且TP含量的变幅明显高于TN含量; 植物叶的N:P和C:N表现为严重退化群落最低, 与退化程度呈负相关; 严重退化群落植物相对于P而言, 总体上表现为缺N; 而恢复群落相对于N而言, 更为缺P, 或同时缺N和P; 群落优势种化学计量学特征对群落演替方向有一定的指示作用。  相似文献   

14.
Several authors have highlighted the potential risks of nanoparticles (NPs). Still, little is known about the magnitude of emissions of NPs from society. Here, the method of explorative particle flow analysis (PFA), a modification of the more well‐known substance flow analysis (SFA), is suggested. In explorative PFA, particle number instead of mass is used as flow and stock metric and explorative scenarios are used to account for potential technology diffusion and, consequently, potentially higher emissions. The method has been applied in a case study of the use phase of titanium dioxide (TiO2) NPs in paint, sunscreen and self‐cleaning cement. The results indicate that the current largest emissions of TiO2 NPs originate from the use of sunscreen. One scenario implies that, in the future, the largest flows and stocks of TiO2 NPs could be related to self‐cleaning cement. Gaps in current knowledge are identified and suggestions for future research are given.  相似文献   

15.
The Sankey diagram is an important aid in pointing up inefficiencies and potential for savings in connection with resource use. This article, the second of a pair, examines the use of Sankey diagrams in operational material flow management. The previous article described the development of the diagram and its use in the past.
Simple Sankey diagrams follow the requirement of conservation of energy or mass and allow a physical view of production systems. Advanced diagrams integrate stocks of materials beside the flows or show the different (ecological) quality of the materials. For the purpose of management, however, a further step is necessary: to illustrate the economic value of the energy and material flows and to use information from cost accounting. The use of flow charts showing added value or the costs of energy and material flows is particularly important for production systems. This article describes examples of each of these uses as well as assumptions that must be taken into account for Sankey diagrams to be used as an effective aid for decision-making in business and public policy.  相似文献   

16.
The Sankey diagram is an important aid in identifying inefficiencies and potential for savings when dealing with resources. It was developed over 100 years ago by the Irish engineer Riall Sankey to analyze the thermal efficiency of steam engines and has since been applied to depict the energy and material balances of complex systems. The Sankey diagram is the main tool for visualizing industrial metabolism and hence is widely used in industrial ecology. In the history of the early 20th century, it played a major role when raw materials were scarce and expensive and engineers were making great efforts to improve technical systems. Sankey diagrams can also be used to map value flows in systems at the operational level or along global value chains. The article charts the historical development of the diagrams. After the First World War the diagrams were used to produce thermal balances of production plants for glass and cement and to optimize the energy input. In the 1930s, steel and iron ore played a strategic role in Nazi Germany. Their efficient use was highlighted with Sankey diagrams. Since the 1990s, these diagrams have become common for displaying data in life cycle assessments (LCAs) of products. Sankey diagrams can also be used to map value flows in systems at the operational level or along global value added chains. This article, the first of a pair, charts the historical development. The companion article discusses the methodology and the implicit assumptions of such Sankey diagrams.  相似文献   

17.
This article, focusing on the flow of bulk construction minerals, establishes a mass balance framework for the North West of England, a region that imports more aggregate material than any other in the United Kingdom. The problems associated with construction minerals are of a different nature than most other resource flow issues: Depletion of resources and contamination are not considered major problems; rather it is the environmental impact resulting from life-cycle stages from extraction, transport, processing, through to final disposal that is most important. A mass balance framework can promote a better understanding of the regional flow of materials, and the impact of human activity on surrounding ecosystems, and hence underpin informed decision making. This is of particular relevance at the current time because increasing political emphasis is placed on sustainable resource management and resource productivity at the United Kingdom and European Union levels. Using a mass balance framework to analyze the sustainability impacts of construction and mineral flows in the North West of England, this study finds that flows resulting from construction activity account for 34,075 terajoules (TJ) of energy resulting in 2,701 gigagrams (Gg) of carbon dioxide emissions related to energy use, and 387 Gg of carbon dioxide emissions related to the transportation of the minerals. Against these impacts, the flow of bulk construction mineral salso supports 147,000 jobs within the region.  相似文献   

18.
Sustainability of urban areas is paramount in the coming years as cities continue to grow in population and resource consumption. A number of methods to model cities have been developed, including material flow analysis and urban metabolism, but these accounting methods do not fully analyze the complex network dynamics present within cities. Ecological network analysis (ENA) provides a new perspective into these urban areas by using metrics designed for analysis of natural ecosystems. This study analyzes 29 urban–industrial ecosystems using ENA, comparing the networks to each other as well as comparing them to previously analyzed eco‐industrial parks and natural food webs. It is found that these systems perform similar to other human‐designed systems, which consistently lack in ecological performance when compared with the natural ecosystems. Additionally, the impact of specific actor types within these networks is shown indicating the importance of industry, agriculture, and the natural environment. Finally, the types of networks are determined to affect the ecological metrics, with the more linear‐based energy networks having the worst performance. This new dataset of ecologically analyzed networks provides a deeper understanding of urban networks and their infrastructure, while providing useful information on how to potentially improve their sustainability.  相似文献   

19.
降水量变化对蒙古栎落叶分解过程的间接影响   总被引:4,自引:1,他引:4  
分析了在4种不同降水量条件下蒙古栎叶凋落物基质质量的变化,并应用分解袋法研究其凋落物在蒙古栎次生林内的分解过程.结果表明:与对照相比,降水量减少条件下,蒙古栎叶凋落物的初始N、P、K浓度显著升高,初始木质素浓度显著降低,凋落物分解速率大,N、P、K矿化率高,N和P固持时间缩短;降水量增加情况下,其凋落物初始N浓度显著降低、木质素浓度显著升高,N、P、K矿化率低,N和P固持时间延长.4种类型叶片凋落物的质量损失过程均符合指数降解模型,分解速率可以由凋落物木质素/N来预测.相关性分析显示,木质素浓度高、N浓度低的两种凋落物的分解速率与N浓度相关性最大;而木质素浓度低、N浓度高的两种凋落物的分解速率与木质素浓度相关性最大.说明降水量的变化显著地改变了蒙古栎叶凋落物的基质质量,进而间接地改变了凋落物的分解过程.  相似文献   

20.
Human activities have significantly intensified natural phosphorus cycles, which has resulted in some serious environmental problems that modern societies face today. This article attempts to quantify the global phosphorus flows associated with present day mining, farming, animal feeding, and household consumption. Various physical characteristics of the related phosphorus fluxes as well as their environmental impacts in different economies, including the United States, European countries, and China, are examined. Particular attention is given to the global phosphorus budget in cropland and the movement and transformation of phosphorus in soil, because these phosphorus flows, in association with the farming sector, constitute major fluxes that dominate the anthropogenic phosphorus cycle. The results show that the global input of phosphorus to cropland, in both inorganic and organic forms from various sources, cannot compensate for the removal in harvests and in the losses by erosion and runoff. A net loss of phosphorus from the world's cropland is estimated at about 10.5 million metric tons (MMT) phosphorus each year, nearly one half of the phosphorus extracted yearly.  相似文献   

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