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1.
Across taxa, individuals vary in how far they disperse, with most individuals staying close to their origin and fewer dispersing long distances. Costs associated with dispersal (e.g., energy, risk) are widely believed to trade off with benefits (e.g., reduced competition, increased reproductive success) to influence dispersal propensity. However, this framework has not been applied to understand variation in dispersal distance, which is instead generally attributed to extrinsic environmental factors. We alternatively hypothesized that variation in dispersal distances results from trade‐offs associated with other aspects of locomotor performance. We tested this hypothesis in the stream salamander Gyrinophilus porphyriticus and found that salamanders that dispersed farther in the field had longer forelimbs but swam at slower velocities under experimental conditions. The reduced swimming performance of long‐distance dispersers likely results from drag imposed by longer forelimbs. Longer forelimbs may facilitate moving longer distances, but the proximate costs associated with reduced swimming performance may help to explain the rarity of long‐distance dispersal. The historical focus on environmental drivers of dispersal distances misses the importance of individual traits and associated trade‐offs among traits affecting locomotion.  相似文献   

2.
Based on institutional and agency theories, this study investigates whether firms use environmental performance as a criterion in incentive schemes for top executives in China, where the weakness of environmental regulations is criticized, and examines the potential moderating effects of board composition on the relationship between environmental performance and top executives’ compensation. Our analysis of 687 publicly traded firms in the manufacturing industry for the period 2008–2010 finds evidence of a positive association between environmental performance and top executives’ compensation. It shows that in firms with Chief Executive Officer–chairperson duality and larger boards, there is a tighter environmental performance–pay relationship, while top executives are found to be rewarded less for environmental performance in firms whose directors hold significant ownership. The presence of independent directors is not found to exert a significant influence on the environmental performance–pay relationship.  相似文献   

3.
1. Ecological trade‐offs in ant (Hymenoptera: Formicidae) assemblages and their implications for coexistence boast a rich history in entomology. Yet investigations of trade‐offs have largely been limited to homogeneous environments. We examined how environmental context modifies trade‐off expression in an ant assemblage spanning a heterogeneous region in central Florida, U.S.A. 2. We examined how trade‐off expression is altered among two contrasting habitat types: open shrub and forest. We tested for the presence of the dominance‐discovery trade‐off and two dominance‐thermal tolerance trade‐offs by estimating behavioral dominance, discovery ability, and thermal tolerance (foraging thermal limit, lethal temperature, and maximal abundance temperature) for a wide range of interacting ant species. 3. We found significantly linear dominance hierarchies in both shrub and forest habitats, showing dominant species out‐compete subordinates for food resources. In thermally stressful shrub habitats, subordinates exhibit higher thermal tolerances, take greater thermal risks, and reach maximum forager abundances at higher temperatures than do dominant species. This suggests temperature mediated trade‐offs control coexistence in shrub habitat. In thermally moderate forest habitat, we found limited evidence for trade‐offs between competitive dominance and resource discovery or between dominance and thermal traits, implying other processes control coexistence. These results demonstrate that trade‐offs controlling ant coexistence may be contingent on environmental context.  相似文献   

4.
The reform in environmental regulations being considered at both federal and state levels is intended to enhance the value and effectiveness of a rule by incorporating risk assessment and cost benefit analysis in the rule making process or regulatory implementation. Although a risk based approach may not provide a panacea to all environmental problem solving, it offers some obvious advantages over the status quo. In particular, it establishes a scientifically defensible basis for evaluating the trade off between risks, costs and benefits in making prudent environmental decisions and developing effective regulatory policies. This paper presents a conceptual framework for risk reduction, summarizes the current status in risk-based legislation at the federal level, provides examples of how various states are using risk based approaches in their regulatory programs, addresses aspects of technical and policy challenges in rule making and other policy and enforcement decisions and provides suggestions for meeting these challenges.  相似文献   

5.
This paper is an inquiry into the circumstances under which the voluntary provision of environmental public goods might be sensible from a firm's point of view. If environmental externalities were the only departure from the economic assumptions of perfect competition, and if no firms had preferential access to superior (low-cost) stocks of natural resources, firms that volunteered to internalize costs could not survive. But because externalities coexist with other departures from the competitive paradigm, such as asymmetric information and oligopoly competition, firms may find it in their shareholders' interests to provide environmental public goods to a greater degree than required by law. A number of firms, especially in Europe and North America, assert that they are pursuing "beyond-compliance" environmental policies. From the perspective of a firm's shareholders, it makes sense to pursue such policies if they increase the firm's expected value or if they appropriately manage business risk.
This paper discusses economically rational explanations for such policies. It analyzes the ways in which a firm's chances of financial success in pursuing any one of them are influenced by the firm's market position and organizational capabilities and by the basic structure of the industry in which it competes.  相似文献   

6.
Although the existing body of empirical literature on the relation between corporate environmental performance (CEP) and corporate financial performance (CFP) is continuously growing, results are still inconclusive about this fundamental question in industrial ecology. Comparisons are difficult because of various estimation methods as well as the overall heterogeneous and complex interaction between the two constructs, but especially because of country‐specific data sets. Consequently, we raise the question of whether regional differences are the driving force buried underneath the inconclusiveness. Therefore, the aim of this article is to explore this heterogeneity by aggregating 893 existing results from 142 empirical primary studies that are based on more than 750,000 firm‐year observations. Our findings suggest a convex impact of a country's economic development on the magnitude of the CEP‐CFP effect (i.e., the effect is positive in developing countries, disappears in emerging countries, and is again positive in highly developed countries). We also find that the overall positive relation strengthens for market‐based CFP measures and diminishes for countries with civil law systems, firms from the service sector, reactive environmental activities, and process‐based CEP measures. Further, several aspects of the examined data sample and the inclusion of relevant control variables explain heterogeneity in previous research results.  相似文献   

7.
Although previous studies point to much (untapped) potential for energy efficiency enhancement in industry, empirical research that adapts findings of environmental control to the context of energy management remains widely neglected. Specifically, previous environmental research suggests that the implementation of energy management control systems (EnMCS) could be an effective lever for companies to enhance their production systems and operations toward energy efficiency. Yet, empirical evidence for this theoretical proposition is rather missing; thus, debate continues regarding whether the high investments to set up a comprehensive EnMCS pay off in the long run. Based on a sample of 236 German manufacturing companies, this study combines primary data that capture the configuration of EnMCS with secondary data that were used to calculate energy efficiency. The results provide evidence that the extent of EnMCS implementation positively relates to firms’ energy efficiency. Findings from additional moderation analysis suggest that companies might enhance the relationship of EnMCS and energy efficiency performance by establishing a full‐time energy manager or by using external energy consulting support.  相似文献   

8.
Species responses to fluctuating environments structure population and community dynamics in variable ecosystems. Although offspring number is commonly used to measure these responses, maternal effects on offspring quality may be an important but largely unrecognised determinant of long‐term population growth. We selected 29 species across a Mediterranean annual plant phylogeny, and grew populations of each species in wet and dry conditions to determine responses in seed number and maternal effects (seed size, seed dormancy, and seedling growth). Maternal effects were evident in over 40% of species, but only 24% responded through seed number. Despite a strong trade‐off between seed size and seed number among species, there was no consistent trade‐off within species; we observed correlations that ranged from positive to negative. Overall, species in this plant guild show a complex range of responses to environmental variation that may be underestimated when only seed number responses are considered.  相似文献   

9.
The environmental effects of e‐commerce may be described in terms of first‐, second‐, and third‐order effects. Data for these effects are scarce, partly because research on environmental effects of e‐commerce and e‐business is still in its infancy, although it is evolving very rapidly. Until now, positive environmental consequences of e‐commerce have generally been coincidental. Two crucial questions that must be addressed are (1) How do we improve our understanding and management of the environmental effects of e‐commerce? and (2) Which approaches are best suited to the development of sustainable e‐solutions? Three approaches to developing sustainable e‐commerce solutions are discussed: the extension of environmental performance measurement and management to e‐commerce activities, the use of new cooperative forms of innovation management, and the provision of customer choice. Finally, an outlook on future research demands is presented. The technology itself (information and communication technologies, Internet) does not determine sustainability, but rather its design, use, and regulation does.  相似文献   

10.
This study investigates the relationship between political connections and corporate environmental performance, and examines the role of government green subsidies on this relationship within the current Chinese context. Using data from publicly traded private manufacturing firms, empirical results show that politically connected firms are significantly more likely to obtain green subsidies than non-connected firms. Assisted by green subsidies, firms with political connections show better environmental performance than those without. Our findings reveal the mechanism by which corporate political connections influence environmental performance.  相似文献   

11.
The skulls of animals have to perform many functions. Optimization for one function may mean another function is less optimized, resulting in evolutionary trade‐offs. Here, we investigate whether a trade‐off exists between the masticatory and sensory functions of animal skulls using echolocating bats as model species. Several species of rhinolophid bats deviate from the allometric relationship between body size and echolocation frequency. Such deviation may be the result of selection for increased bite force, resulting in a decrease in snout length which could in turn lead to higher echolocation frequencies. If so, there should be a positive relationship between bite force and echolocation frequency. We investigated this relationship in several species of southern African rhinolophids using phylogenetically informed analyses of the allometry of their bite force and echolocation frequency and of the three‐dimensional shape of their skulls. As predicted, echolocation frequency was positively correlated with bite force, suggesting that its evolution is influenced by a trade‐off between the masticatory and sensory functions of the skull. In support of this, variation in skull shape was explained by both echolocation frequency (80%) and bite force (20%). Furthermore, it appears that selection has acted on the nasal capsules, which have a frequency‐specific impedance matching function during vocalization. There was a negative correlation between echolocation frequency and capsule volume across species. Optimization of the masticatory function of the skull may have been achieved through changes in the shape of the mandible and associated musculature, elements not considered in this study.  相似文献   

12.
Previous empirical work suggests that firms with high environmental performance tend to be profitable, but questions persist about the nature of the relationship. Does stronger environmental performance really lead to better financial performance, or is the observed relationship the outcome of some other underlying firm attribute? Does it pay to have cleanrunning facilities or to have facilities in relatively clean industries? To explore these questions, we analyze 652 U.S. manufacturing firms over the time period 1987–1996. Although we find evidence of an association between lower pollution and higher financial valuation, we find that a firm's fixed characteristics and strategic position might cause this association. Our findings suggest that “When does it pay to be green?” may be a more important question than “Does it pay to be green?”  相似文献   

13.
Modular construction practices are used in many countries as an alternative to conventional on‐site construction for residential homes. While modular home construction has certain advantages in terms of material and time efficiency, it requires a different infrastructure than conventional home construction, and the overall environmental trade‐offs between the two methods have been unclear. This study uses life cycle assessment to quantify the environmental impacts of constructing a typical residential home using the two methods, based on data from several modular construction companies and conventional homebuilders. The study includes impacts from material production and transport, off‐site and on‐site energy use, worker transport, and waste management. For all categories considered, the average impacts of building the home are less for modular construction than for conventional construction, although these averages obscure significant variation among the individual projects and companies.  相似文献   

14.
Cognitive performance is based on brain functions, which have energetic demands and are modulated by physiological parameters such as metabolic hormones. As both environmental demands and environmental energy availability change seasonally, we propose that cognitive performance in free‐living animals might also change seasonally due to phenotypic plasticity. This is part of an emerging research field, the ‘ecophysiology of cognition’: environmentally induced changes in physiological traits, such as blood glucose and hormone levels, are predicted to influence cognitive performance in free‐living animals. Energy availability for the brain might change, and as such cognition, with changing energetic demands (e.g. reproduction) and changes of energy availability in the environment (e.g. winter, drought). Individuals spending more energy than they can currently obtain from their environment (allostatic overload type I) are expected to trade off energy investment between cognition and other life‐sustaining processes or even reproduction. Environmental changes reducing energy availability might thus impair cognition. However, selection pressures such as predation risk, mate choice or social demands may act on the trade‐off between energy saving and cognition. We assume that different environmental conditions can lead to three different trade‐off outcomes: cognitive impairment, resilience or enhancement. Currently we cannot understand these trade‐offs, because we lack information about changes in cognitive performance due to seasonal changes in energy availability and both the resulting changes in homeostasis (for example, blood glucose levels) and the associated changes in the mechanisms of allostasis (for example, hormone levels). Additionally, so far we know little about the fitness consequences of individual variation in cognitive performance. General cognitive abilities, such as attention and associative learning, might be more important in determining fitness than complex and specialized cognitive abilities, and easier to use for comparative study in a large number of species. We propose to study seasonal changes in cognitive performance depending on energy availability in populations facing different predation risks, and the resulting fitness consequences.  相似文献   

15.
Although business firms have improved their environmental performance, a variety of forces are pushing businesses toward adopting environmental management throughout the entire life cycle of their products and processes. In this article we discuss the information systems elements of an environmental management approach we call "life-cycle-oriented environmental management" (LCOEM).This approach requires the firm to manage the effects of its processes from the creation of inputs to the final disposal of outputs, that is, from cradle to grave. We present a framework of the classes of information systems needed, describe their use in an LCOEM setting and define their inter relationships. We conclude with a discussion of the implications of LCOEM information systems.  相似文献   

16.
This article proposes a linear programming model that is based on the wastewater treatment input‐output model (W2IO) to identify the lowest‐emission choice among alternative feasible options for wastewater treatment; this model can be considered as an application of the waste input‐output linear programming model (WIO‐LP) to wastewater issues. Using the data of the Tokyo metropolitan W2IO table, I apply this model to obtain the optimal wastewater treatment options under alternative scenarios. The Pareto frontiers of environmental loads are derived to show the trade‐off relationships among various types of environmental load and the effect of the introduction of high‐temperature incineration of dewatered sludge on the generation of environmental loads. The main conclusion of the study is that when all three types of environmental load (landfill level, global warming potential, and chemical oxygen demand) are considered, the introduction of high‐temperature incineration causes the widening of the Pareto frontier of environmental loads and also causes it to move closer to the origin.  相似文献   

17.
As pollution emitters and energy users, firms are important causes of environmental problems, making it increasingly vital for them to strengthen their environmental management and information disclosure policies. However, firms doubt whether it pays to be green and whether it is worthwhile to disclose their environmental information, and there are hot debates on these questions in the literature. This paper analyzes the relationships among corporate environmental performance, environmental information disclosure, and financial performance in China, which witnessed rapid growth at the price of environmental degradation. With 950 observations from 475 Chinese listed companies between 2013 and 2014, we find a U-shaped nonlinear relationship between corporate environmental performance and environmental disclosure, an insignificant relationship between environmental performance and financial performance, and a negative relationship between environmental disclosure and financial performance, which is different from most findings in developed countries. The aforementioned results imply that Chinese firms have few motivations to disclose environmental information or improve environmental performance; therefore, mandatory disclosure of environmental information is necessary, and proper environmental policy should be made to punish environmental violations and encourage better environmental performance.  相似文献   

18.
Industrial symbiosis (IS), where different entities collaborate in the management of energy, utilities, materials, or services, has been identified as an approach to improve resource efficiency and circularity in industry. This article assesses the environmental performance of an IS network with firms involved in waste management, soil, surfaces, paper, lumber, and energy. The aim is to highlight the environmental performance of an IS network and pay particular attention to the improved performance for products in the IS network. Life cycle assessment is used to compare the current IS network with a reference scenario and a potential future development. The results suggest that there are significant benefits from the IS network. Large reductions in greenhouse gas (GHG) emissions and abiotic resource depletion were identified. Furthermore, large reductions in local impacts, namely eutrophication and acidification impacts are illustrated. It was shown that all firms in the network benefit from the synergies involved, with a large share of the benefits stemming from the facilitated exchanges with the waste management company. The replacement of conventional products and energy streams with bio‐based counterparts from within the network is of significant importance. Finally, the results point to the importance of the facilitation of by‐product synergies, and the significant value this creates in the region, with large potential to improve the environmental performance of firms and their products.  相似文献   

19.
A longstanding idea in evolutionary physiology is that an enzyme cannot jointly optimize performance at both high and low temperatures due to a trade‐off between stability and activity. Although a stability‐activity trade‐off has been observed for well‐characterized examples, such a trade‐off is not imposed by any physical chemical constraint. To better understand the pervasiveness of this trade‐off, I investigated the stability‐activity relationship for comparative biochemical studies of purified orthologous enzymes identified by a literature search. The nature of this relationship varied greatly among studies. Notably, studies of enzymes with low mean synonymous nucleotide sequence divergence were less likely to exhibit the predicted negative correlation between stability and activity. Similarly, a survey of directed evolution investigations of the stability‐activity relationship indicated that these traits are often uncoupled among nearly identical yet phenotypically divergent enzymes. This suggests that the presumptive trade‐off often reported for investigations of enzymes with high mean sequence divergence may in some cases instead be a consequence of the degeneration over time of enzyme function in unselected environments, rather than a direct effect of thermal adaptation. The results caution against the general assertion of a stability‐activity trade‐off during enzyme adaptation.  相似文献   

20.
Our article uses the theory of transaction cost economics as a conceptual basis for examining the contracting mechanisms by which firms in the computer industry structure programs to encourage their suppliers to improve their environmental management systems and/or the environmental quality of their products. We explore the economic transactions hazards associated with asking suppliers to invest in the specialized technologies required to improve environmental performance of products and management practices and the relational contracting mechanisms computer industry firms are using to protect themselves against these hazards. We also describe the importance the managers we interviewed attributed to various transactions hazards and their perceptions of how well their firms were coping with them. We conclude by discussing questions for future research. By using TCE to frame our analysis of how computer manufacturers are structuring their relationships with their suppliers in the environmental area, we hope to show how social science theory can be used to enrich and increase the practicality of the work done by engineers and others in the mainstream areas of the industrial ecology field.  相似文献   

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