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1.
Strategies are needed for reconciling competing demands at the regional level when areas are to be selected for protection and there are associated costs, possibly equivalent to forgone development opportunties. As an alternative to the fixed scaling (or weighting) of costs and benefits required by cost-benefit analysis, multi-criteria analyses allow the exploration of alternative weightings and a summary trade-off curve to determine preferred solutions. For alternative sets of areas, total cost could be plotted against total represented biodiversity, but a more consistent approach should look at trade-off space at the level of individual areas. For a given weighting, an area is assigned protection if and only if its contribution to total biodiversity, CB, exceeds its equivalent cost, EC (in biodiversity units). Because CB for a given area depends on which other areas are also protected, it can be more or less than EC. Here we develop an iterative strategy for selecting areas, such that, for a given weighting, an area is in the final protected set if and only if its final CB value is greater than its EC value. Sensitivity analysis is used to identify those areas that: (1) are assigned protection even when low weight is given to biodiversity, or (2) are not assigned protection even when high weight is given to biodiversity. This approach is applicable in principle to any surrogate measure for biodiversity; here examples are presented in which environmental data are summarized as an environmental space.  相似文献   

2.
This article addresses the need for a structured and compre-hensive methodology for assessing the environmental perfor-mance of manufacturing processes. The analytic hierarchy pro-cess (AHP) is used as the basic framework for analyzing environmental impacts and improvement options following a streamlined life-cycle assessment (LCA) approach that is fo-cused on the manufacturing operation. The multicriteria de-cision analysis approach of the AHP is consistent with the LCA concept because the environmental factors can be hierarchi-cally structured into impacts and improvement options. Its po-tential as a valuation tool for impact and improvement assess-ment addresses both qualitative and quantitative issues in environmental decision making.
Through application to a pulp and paper manufacturing case study, the viability of the AHP for evaluating environmen-tal impacts and prioritizing process improvement options rela-tive to these impacts is demonstrated. AHP was used to pro-vide a quantitative tool for the design of a set of weighting factors for impact and improvement analyses.  相似文献   

3.
1. The non-linear responses of environmental systems to changes imposed upon them is well known to scientists. Environmental managers rarely act accordingly, however, because of communication problems, a lack of imagination and various other constraints. Therefore, we illustrate such non-linear responses to demonstrate that gains in efficiency (benefit per money spent) can be made by integrating these characteristics into decision making.
2. Identifying three measures that are currently the focus of large freshwater management budgets (waste-water treatment, riparian buffer strips and discharge allocations to regulated rivers), we relate the costs of these measures to the environmental improvements achievable in running waters. For each of these measures, the environmental improvement achieved per currency unit significantly decreases with an increase in total money spent.
3. Traditional environmental management ignores this system behaviour because it invests important parts of budgets in a particular measure before focusing on the next among other measures. We therefore advocate alternating investments in that measure which achieves the greatest environmental improvement in the next possible investment step. Compared with traditional management, this alternating decision-making strategy will achieve greater environmental improvements for a given total budget.  相似文献   

4.
1. The non-linear responses of environmental systems to changes imposed upon them is well known to scientists. Environmental managers rarely act accordingly, however, because of communication problems, a lack of imagination and various other constraints. Therefore, we illustrate such non-linear responses to demonstrate that gains in efficiency (benefit per money spent) can be made by integrating these characteristics into decision making.
2. Identifying three measures that are currently the focus of large freshwater management budgets (waste-water treatment, riparian buffer strips and discharge allocations to regulated rivers), we relate the costs of these measures to the environmental improvements achievable in running waters. For each of these measures, the environmental improvement achieved per currency unit significantly decreases with an increase in total money spent.
3. Traditional environmental management ignores this system behaviour because it invests important parts of budgets in a particular measure before focusing on the next among other measures. We therefore advocate alternating investments in that measure which achieves the greatest environmental improvement in the next possible investment step. Compared with traditional management, this alternating decision-making strategy will achieve greater environmental improvements for a given total budget.  相似文献   

5.
The study fills the gap in existing literature by comparing the economic costs and environmental impacts of processes in four services companies in Europe and the United States. Process-based life cycle assessment (LCA) and the case study method are used to compare companies both on four global-scale impacts and on environmental intensity (impacts per unit cost). The study builds on prior publications on the environmental contribution of processes. The processes include all the activities of the companies that result in an entry into the bookkeeping records. The results show that despite the substantial differences in organizational characteristics and line of business, all the cases had similar environmental contributions and intensity profiles. Wages, which accounted for over half of the costs, were assumed not to cause any environmental impacts. By contrast, the office premises, which generated less than 10% of the costs, caused around 50% of the environmental impacts. At a more general level, the results suggest that both the high environmental impact and the high intensity are attributed mostly to a few premises-related processes in the services industry. The results also seem to imply that the companies could gain added value by using life cycle assessment in determining the significant environmental impacts of their operations.  相似文献   

6.
7.
基于流域复合生态系统阈值特性的动态赋权理论分析   总被引:1,自引:0,他引:1  
本文基于流域开发复合生态环境系统累积环境效应的产生机理,以及系统的非线性动力学特征和累积环境效应反应过程特征曲线,提出了时序多指标决策理论模式,建立了复合生态环境效应的动态监测因子确定评判标度的量化模型.建立的动态决策理论是在决策空间和目标空间基础上,引入时间和空间参数,使决策过程与结果充分体现了时序特征,对生态系统规划决策和区域环境长期或不定期动态评估具有一定的指导.  相似文献   

8.
As the largest developing country, China has been suffering from resource shortage and serious environmental pollution. Evaluation and improvement of the regional environmental efficiency is crucial to pursuing the balance between economic development and environmental protection. This paper used a regional environmental efficiency SBM (slack-based measure) (REES) model which treats environmental pollution as undesirable outputs to evaluate the environmental efficiency of 30 provincial administrative regions (PARs) in China from 2005 to 2011 and investigated the factors affecting environmental efficiency using the Tobit regression model. The results indicate that there is distinct difference in environmental efficiency amongst each PAR. The GDP per capita, industrial structure, innovation capability, environmental awareness of local government and population density have significant positive impacts, while energy intensity exerts a significantly negative effect on environmental efficiency. In order to make more effective policies for improving China’s regional environmental efficiency, the hierarchical cluster analysis was applied to divide the 30 PARs into 3 sub-regions. A number of policy recommendations were provided for improving environmental efficiency according to the characteristics of each sub-region, which are helpful for the Chinese government to achieve the targets of environmental protection along with the economic development in the coming years.  相似文献   

9.
Managers, management scholars, regulators, nonprofit organizations, and the media are increasingly using emissions inventory data to measure organizations' environmental performance. Whereas some analysts use total mass emitted, others have applied one or more of the growing number of toxicity-weighting databases aimed at predicting the environmental and health impacts of emissions. Little research is available to guide analysts in selecting among these databases. This article compares 13 methods in terms of their sophistication, complexity, and comprehensiveness. Seven of these methods are then evaluated as to their usefulness in weighting emissions data from the U.S. Environmental Protection Agency's (U.S. EPA's) toxic release inventory, and three pair-wise comparisons are conducted. We recommend the U.S. EPA's Risk Screening Environmental Indicators for estimating impacts to human health. We recommend the Tool for the Reduction and Assessment of Chemical Impacts for estimating impacts to human health and the environment.  相似文献   

10.
Eco-efficiency and Its xsTerminology   总被引:1,自引:0,他引:1  
Eco-efficiency has been defined as a general goal of creating value while decreasing environmental impact. Leaving out the normative part of this concept, the empirical part refers to a ratio between environmental impact and economic cost or value. Two basic choices must be made in defining practical eco-efficiency: which variable is in the denominator and which is in the numerator; and whether to specify environmental impact or improvement and value created or cost. Distinguishing between two situations, the general one of value creation and the specific one of environmental improvement efforts, and leaving the numerator-denominator choice to the user, as diverging practices have developed, four basic types of ecoefficiency result: environmental intensity and environmental productivity in the realm of value creation; and environmental improvement cost and environmental cost-effectiveness in the realm of environmental improvement measures.  相似文献   

11.
Quantitative genetic models of evolution of phenotypic plasticity are used to derive environmental tolerance curves for a population in a changing environment, providing a theoretical foundation for integrating physiological and community ecology with evolutionary genetics of plasticity and norms of reaction. Plasticity is modelled for a labile quantitative character undergoing continuous reversible development and selection in a fluctuating environment. If there is no cost of plasticity, a labile character evolves expected plasticity equalling the slope of the optimal phenotype as a function of the environment. This contrasts with previous theory for plasticity influenced by the environment at a critical stage of early development determining a constant adult phenotype on which selection acts, for which the expected plasticity is reduced by the environmental predictability over the discrete time lag between development and selection. With a cost of plasticity in a labile character, the expected plasticity depends on the cost and on the environmental variance and predictability averaged over the continuous developmental time lag. Environmental tolerance curves derived from this model confirm traditional assumptions in physiological ecology and provide new insights. Tolerance curve width increases with larger environmental variance, but can only evolve within a limited range. The strength of the trade‐off between tolerance curve height and width depends on the cost of plasticity. Asymmetric tolerance curves caused by male sterility at high temperature are illustrated. A simple condition is given for a large transient increase in plasticity and tolerance curve width following a sudden change in average environment.  相似文献   

12.
With the objective of evaluating measures of milk yield persistency, 27,000 test-day milk yield records from 3362 first lactations of Brazilian Gyr cows that calved between 1990 and 2007 were analyzed with a random regression model. Random, additive genetic and permanent environmental effects were modeled using Legendre polynomials of order 4 and 5, respectively. Residual variance was modeled using five classes. The average lactation curve was modeled using a fourth-order Legendre polynomial. Heritability estimates for measures of persistency ranged from 0.10 to 0.25. Genetic correlations between measures of persistency and 305-day milk yield (Y305) ranged from -0.52 to 0.03. At high selection intensities for persistency measures and Y305, few animals were selected in common. As the selection intensity for the two traits decreased, a higher percentage of animals were selected in common. The average predicted breeding values for Y305 according to year of birth of the cows had a substantial annual genetic gain. In contrast, no improvement in the average persistency breeding value was observed. We conclude that selection for total milk yield during lactation does not identify bulls or cows that are genetically superior in terms of milk yield persistency. A measure of persistency represented by the sum of deviations of estimated breeding value for days 31 to 280 in relation to estimated breeding value for day 30 should be preferred in genetic evaluations of this trait in the Gyr breed, since this measure showed a medium heritability and a genetic correlation with 305-day milk yield close to zero. In addition, this measure is more adequate at the time of peak lactation, which occurs between days 25 and 30 after calving in this breed.  相似文献   

13.
This study compares equity funds that are managed according to sustainability goals with conventionally managed funds with respect to their environmental impacts. Overlap in the portfolios of sustainable equity funds and conventional equity funds can be very large. Further, the sector allocation of both types of funds is generally very similar, because portfolio managers follow a chosen benchmark to minimize risk. These two effects may result in no difference existing between the two types of funds in terms of their environmental impact and damage (null hypothesis of this research). This study comparatively assesses the environmental impact of portfolios of 26 investment funds: 13 sustainable investment funds and 13 conventional funds, which are managed according to the benchmark MSCI World. The study applies input–output life-cycle assessment (IO-LCA) in combination with a simulation of company-specific environmental performance. The environmental impact is evaluated per functional unit for each fund, measured as the risk-adjusted financial performance. The statistical analysis showed that the analyzed sustainable investment funds performed better with respect to environmental impact assessment but worse in economic risk-adjusted performance (RAP) over the period 2000-2004. In 2004, however, the RAP of the selected sustainable investment funds showed better performance. Both samples considerably overlap for the environmental and economic parameters. The results suggest that the environmental impact of sustainable investment funds in the sample is slightly less than that of conventional funds.  相似文献   

14.
Durability and kinematics are two critical factors which must be considered during total knee replacement (TKR) implant design. It is hypothesized, however, that there exists a competing relationship between these two performance measures, such that improvement of one requires sacrifice with respect to the other. No previous studies have used rigorous and systematic methods to quantify this relationship. During this study, multiobjective design optimization (MOO) using the adaptive weighted sum (AWS) method is used to determine a set of Pareto-optimal implant designs considering durability and kinematics simultaneously. Previously validated numerical simulations and a parametric modeller are used in conjunction with the AWS method in order to generate a durability-versus-kinematics Pareto curve. In terms of kinematics, a design optimized for kinematics alone outperformed a design optimized for durability by 61.8%. In terms of durability, the design optimized for durability outperformed the kinematics-optimized design by 70.6%. Considering the entire Pareto curve, a balanced (1:1) trade-off could be obtained when equal weighting was placed on both performance measures; however improvement of one performance measure required greater sacrifices with respect to the other when the weighting was extremized. For the first time, the competing relationship between durability and kinematics was confirmed and quantified using optimization methods. This information can aid future developments in TKR design and can be expanded to other total joint replacement designs.  相似文献   

15.

Purpose

The main goal of any life cycle assessment (LCA) study is to identify solutions leading to environmental savings. In conventional LCA studies, practitioners select from some alternatives the one which better matches their preferences. This task is sometimes simplified by ranking these alternatives using an aggregated indicator defined by attaching weights to impacts. We address here the inverse problem. That is, given an alternative, we aim to determine the weights for which that solution becomes optimal.

Methods

We propose a method based on linear programming (LP) that determines, for a given alternative, the ranges within which the weights attached to a set of impact metrics must lie so that when a weighting combination of these impacts is optimized, the alternative can be optimal, while if the weights fall outside this range, it is guaranteed that the solution will be suboptimal. A large weight value implies that the corresponding LCA impact is given more importance, while a low value implies the converse. Furthermore, we provide a rigorous mathematical analysis on the implications of using weighting schemes in LCA, showing that this practice guides decision-making towards the adoption of some specific alternatives (those lying on the convex envelope of the resulting trade-off curve).

Results and discussion

A case study based on the design of hydrogen infrastructures is taken as a test bed to illustrate the capabilities of the approach presented. Given are a set of production and storage technologies available to produce and deliver hydrogen, a final demand, and cost and environmental data. A set of designs, each achieving a unique combination of cost and LCA impact, is considered. For each of them, we calculate the minimum and maximum weight to be given to every LCA impact so that the alternative can be optimal among all the candidate designs. Numerical results show that solutions with lower impact are selected when decision makers are willing to pay larger monetary penalties for the environmental damage caused.

Conclusions

LP can be used in LCA to translate the decision makers’ preferences into weights. This information is rather valuable, particularly when these weights represent economic penalties, as it allows screening and ranking alternatives on the basis of a common economic basis. Our framework is aimed at facilitating decision making in LCA studies and defines a general framework for comparing alternatives that show different performance in a wide variety of impact metrics.  相似文献   

16.
At least three perspectives—industrial ecology (IE), ecological modernization theory (EMT), and the “environmental Kuznets curve” (EKC)—emphasize the potential for sustainability via refinements in production systems that dramatically reduce the environmental impacts of economic development. Can improvements in efficiency counterbalance environmental impacts stemming from the scale of production? To address this question we analyze cross‐national variation in the ecological footprint (EF) per unit of gross domestic product (GDP). The EF is a widely recognized indicator of human pressure on the environment. The EF of a nation is the amount of land area that would be required to produce the resources it consumes and to absorb the wastes it generates. The most striking finding of our analyses is that there is limited variation across nations in EF per unit of GDP. This indicates limited plasticity in the levels of EF intensity or eco‐efficiency among nations, particularly among affluent nations. EF intensity is lowest (ecoefficiency is highest) in affluent nations, but the level of efficiency in these nations does not appear to be of sufficient magnitude to compensate for their large productive capacities. These results suggest that modernization and economic development will be insufficient, in themselves, to bring about the ecological sustainability of societies.  相似文献   

17.
The rapid development of information and communications technology (ICT) is providing new ways to access media content. Electronic media are sometimes more advantageous from an environmental perspective than paper‐based media solutions, but ICT‐based media can also bring environmental burdens. This study compared the potential environmental impacts in a life cycle perspective of a print edition of a magazine and that of its electronic edition read on a tablet device. Important objectives were to identify activities giving rise to the main environmental impacts for both the print and tablet editions, determine the key factors influencing these impacts, and address data gaps and uncertainties. A detailed assessment of the tablet edition is provided in a previous article (part 1), whereas this article compares it with the print edition. The methodology used was life cycle assessment and the environmental impacts assessed included climate change, cumulative energy/exergy demand, metal depletion, photochemical oxidant formation, particulate matter formation, terrestrial acidification, freshwater eutrophication, marine eutrophication, and fossil depletion. Use of different functional units to compare the print and tablet editions of the magazine resulted in different relative environmental impacts. In addition, emerging (low number of readers and low reading time per copy) and mature (higher number of readers and higher reading time per copy) tablet editions yielded varying results. The emerging tablet edition resulted in higher potential environmental impacts per reader than the print edition, but the mature tablet edition yielded lower impacts per reader in half the impact categories assessed. This illustrates the importance of spreading the environmental impacts over a large number of readers. The electricity mix used in product system processes did not greatly affect the results of tablet/print comparisons, but overall number of readers for the tablet edition, number of readers per copy for the print edition, file size, and degree of use of the tablet device proved crucial for the comparison results.  相似文献   

18.

-

DOI: http://dx.doi.org/10.1065/lca2006.04.017

Background, Aims and Scope

Social impacts in supply chains and product life cycles are of increasing interest to policy makers and stakeholders. Work is underway to develop social impact indicators for LCA, and to identify the social inventory data that will drive impact assessment for this category. Standard LCA practice collects and aggregates inventory data of the form \units of input or output (elementary flow) per unit of process output.\ Measurement of social impacts within workplaces as well as host communities and societies poses new challenges not heretofore faced by LCA database developers. Participatory measurement and auditing of social impacts and of workplace health issues has been shown to provide important benefits relative to external auditor-based methods, including greater likelihood of detecting rights abuses, and stronger support of subsequent action for improvement. However, nonstandardized auditing and metrics poses challenges for the supply chain-wide aggregation and comparison functions of LCA. An analogous challenge arises in the case of resource extractive processes, for which the certification of best management practices provides an important and practical environmental metric. In both the social and resource extraction examples, it may be that attributes of the process are more valuable metrics to measure and incentivize than measured quantities per unit of process output. But how to measure, how to aggregate across life cycles, how to compare product life cycles, and how to incentivize progress as with product policy?

Methods

A methodology is presented and demonstrated which estimates the health impacts of economic development stemming from product life cycles. This methodology does not introduce new social indicators; rather, it works with the already common LCA endpoint of human health, and introduces and applies a simplified empirical relationship to characterize the complex pathways from product life cycles' economic activity to health in the aggregate.

Results

A simple case study indicates that the health benefits of economic development impacts in product life cycles have the potential to be very significant, possibly even orders of magnitude greater than the health damages from the increased pollution. While the simple macro model points up the dramatic importance of socio-economic pathways to health in product life cycles, it lacks any sensitivity to the vitally important, contextspecific attributes of the economic development associated with each process. This result begs the question of how to measure, aggregate, compare, and stimulate society-wide improvement of context-dependent attributes within and across product life cycles in LCA.

Discussion

Before attempting an answer to the question noted above, a brief reconsideration is offered concerning life cycle assessment. Namely, where does it come from, and what does it bring?

Recommendations and Outlook

Finally, the paper concludes by sketching a life cycle approach to promoting localized assessments, to summarizing their results over supply chains and life cycles, and to comparing product life cycles in terms of their results. Often, localized assessments will yield information on the attributes of a process, rather than (or in addition to) the traditional form of life cycle inventory information, which is \units of something per unit of process output.\ The methodology can enable product policy users to promote reporting of basic attributes of processes within supply chains, together with local measurement and reporting of context-relevant impacts. For attributes linked to progress on impacts of local and global concern, promotion of these attributes within supply chain processes will bring strong benefits. In addition, over time it may be possible for researchers to develop and refine models that estimate, based on cross-sectional and time series analysis of attributes and impacts, relationships between attributes and impacts. In any case, while local impacts across supply chains may not be precisely knowable – let alone controllable – by a microdecision maker at the time of their product-related decision, life cycle attribute analysis may give such decision makers an opportunity to empower progress throughout life cycles and supply chains, which is after all a motivating goal of LCA.
  相似文献   

19.
The environmental changes induced by projects occurring in an area are evaluated by cumulative impact assessments (CIA), which consider the consequences of multiple projects, each insignificant on its own, yet important when evaluated collectively. When future human activities are of interest, the proposed activities are included in CIA using an analytical platform that can supply precise predictions but with asymptotically null accuracy. To compensate for the lack of accuracy we propose a shift in the paradigm governing CIA. The paradigm shift advocates a change in the focus of CIA investigations from the detailed analysis of one unlikely future to the identification of patterns describing the future changes in the environment. To illustrate the paradigm shift, a set of 144 possible and equally likely futures were developed and used to identify the potential impacts of forest harvesting and petroleum drilling on the habitat of moose and marten. The univariate and multivariate analysis of two measures of habitat, namely average habitat suitability index (HSI) and surface of the stands with HSI >0.5, revealed at least three distinct periods in the next 100 years. Multivariate analysis also showed that habitat quality is of immediate importance and marten is sensitive during the first third of the century. Our findings indicate that the spatial and temporal arrangement of the human disturbances could be more important than the magnitude of the disturbance. The attributes associated with significant environmental changes are harvesting age and the investigated environmental elements of an ecosystem, in this case the species habitat.  相似文献   

20.
In this paper, we develop a method to assess the environmental impacts of metal scenarios. The method is life cycle based, but enables forward looking and upscaling. The method aims at translating metal demand scenarios into technology‐specific supply scenarios, necessary to make the translation into environmental impacts. To illustrate the different steps of the methodology, we apply it to the case of seven major metals. Demand scenarios for seven major metals are taken from literature. We translate those into technology‐specific supply scenarios, and future time series of environmental impacts are specified including recycling rates, energy system transformation, efficiency improvement, and ore grade decline. We show that the method is applicable and may lead to relevant and, despite many uncertainties, fairly robust results. The projections show that the environmental impacts related to metal production are expected to increase steeply. Iron is responsible for the majority of impacts and emissions are relatively unaffected by changes in the production and energy system. For the other metals, the energy transition may have substantial benefits. By far, the most effective option for all metals appears to be to increase the share of secondary production. This would reduce emissions, but is expected to become effective only in the second half of the twenty‐first century. The circular economy agenda for metals is therefore a long‐term agenda, similar to climate change: Action must be taken soon while benefits will become apparent only at the long term.  相似文献   

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