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691.
Risk compensation denotes offsetting behavioral responses to safety improvements. Theoretical arguments suggest that, when drivers are required to drive safer cars or drive in a safer manner, they will tend to increase their driving speed or drive in some other risky manner. The purpose of this paper is to review critically the theory and evidence on risk compensation. Our general conclusion is that the application of risk compensation theory, especially to some types of regulations, is questionable, and the empirical support for significant offsetting behavior is weak. Specifically—(1) the role of limitations in processing information is not appreciated, especially regarding risk perceptions and the learning component associated with new regulations; (2) the types of regulations and types of driving behavior are not adequately distinguished; and (3) the empirical studies haves mixed results and are subject to important limitations. 相似文献
692.
When populations decline in response to unfavorable environmental change, the dynamics of their population growth shift. In populations that normally exhibit high levels of variation in recruitment and abundance, as do many amphibians, declines may be difficult to identify from natural fluctuations in abundance. However, the onset of declines may be evident from changes in population growth rate in sufficiently long time series of population data. With data from 23 years of study of a population of Fowler's toad (Anaxyrus [ = Bufo] fowleri) at Long Point, Ontario (1989–2011), we sought to identify such a shift in dynamics. We tested for trends in abundance to detect a change point in population dynamics and then tested among competing population models to identify associated intrinsic and extrinsic factors. The most informative models of population growth included terms for toad abundance and the extent of an invasive marsh plant, the common reed (Phragmites australis), throughout the toads’ marshland breeding areas. Our results showed density‐dependent growth in the toad population from 1989 through 2002. After 2002, however, we found progressive population decline in the toads associated with the spread of common reeds and consequent loss of toad breeding habitat. This resulted in reduced recruitment and population growth despite the lack of significant loss of adult habitat. Our results underscore the value of using long‐term time series to identify shifts in population dynamics coincident with the advent of population decline. Efectos de una Planta Invasora sobre las Dinámica Poblacional de Sapos 相似文献
693.
Johnnie N. Moore Alicia S. Arrigoni Andrew C. Wilcox 《Journal of the American Water Resources Association》2012,48(5):925-938
Moore, Johnnie N., Alicia S. Arrigoni, and Andrew C. Wilcox, 2012. Impacts of Dams on Flow Regimes in Three Headwater Subbasins of the Columbia River Basin, United States. Journal of the American Water Resources Association (JAWRA) 48(5): 925‐938. DOI: 10.1111/j.1752‐1688.2012.00660.x Abstract: We compared long‐term changes in flow regimes resulting from climate change with those resulting from dams in three matched pairs of natural and modified headwater subbasins of the Columbia River. Based on the analysis of 12 flow‐regime metrics, we found that damming had minimal effect on most quantity of flow metrics, but major effect on timing of flow metrics, especially those representing “spring runoff.” In all modified subbasins, “spring runoff” metrics occurred much earlier than natural flow (up to ~44 days earlier for April‐July flows). Storage capacity modulated the magnitude of timing of flow‐metric changes, with the largest storage capacity leading to the most change. However, even in subbasins with low storage capacity, we found significant change in most timing of flow metrics. We also found that damming, especially in subbasins with higher storage capacity, overwhelmed climate variability in all basins for most flow metrics. This shows that reservoir operations need to be modified to more closely match the natural timing of flow regimes to promote positive ecologic response in modified rivers, even in basins where quantity of flow metrics have not changed substantially as a result of damming. 相似文献
694.
Pablo del Río Miguel Ángel Tarancón Morán Fernando Callejas Albiñana 《Journal of Cleaner Production》2011,19(11):1170-1179
The aim of this paper is to empirically assess the determinants of environmental technology investments in the Spanish industrial sectors with the help of panel data econometric techniques. The paper confirms the relevance of the stringency of environmental regulation to explain overall investment patterns in environmental technologies. These investments are also positively related to human and physical capital intensity and R&D intensity, and negatively related to the export intensity of sectors. Furthermore, the study shows that the determinants for investments are likely to differ between environmental technology types (i.e., end-of-pipe versus cleaner technologies). 相似文献
695.
We consider the auditing problem of an environmental enforcement agency with fixed audit resources: How to decide which firms to audit after having observed the firms' taxable emissions reports. The goal of the agency is to implement the socially efficient emissions level. The audit mechanism is the agency's sole choice variable, while other variables such as the tax rate on emissions and the fine for non-compliance are determined by other governmental actors. The fines and budget of the agency are constrained in such a way that the common random audit mechanism fails to implement socially efficient emissions. Assuming perfect information among the firms, we derive an optimal audit mechanism capable of implementing the socially efficient emissions level. The optimal audit mechanism creates a contest exploiting the strategic interdependencies between the firms, where the probability of winning (not being audited) for each firm depends on costly efforts (their taxable emissions reports). 相似文献
696.
Risk-based regulation has become increasingly popular in recent years. Proponents argue that it facilitates robust governance, contributing to efficient and effective use of regulatory resources and delivering interventions in proportion to risk. Critics contend that the challenges of operationalising risk-based governance mitigate its potential benefits. In this paper we start by considering what we mean by risk-based governance and discuss some of the factors shaping the adoption of such strategies. We then consider the development and operation of risk-based approaches in the environmental policy domain, focusing specifically on the regulation of contaminated land and radioactive waste. We argue that whilst risk-based approaches can offer important benefits, they face a range of epistemic, institutional and normative challenges that can play an important role in shaping the way that organisations manage both risks to society and their own institutional risks. This has profound implications for achieving regulatory objectives and, for this paper, the environmental outcomes that the regulations are designed to deliver. 相似文献
697.
中国水资源管理博弈特征分析 总被引:12,自引:1,他引:11
随着中国水资源匮乏和水污染态势日益严峻.建立一个面向效率和公平的水资源管理机制的需求日益凸现。本文在比较传统行政模式和市场模式下水权管理不同特征的基础上,分别从静态和动态两个角度.从水量和水质两个维度分析了两种模式下的水用户博弈特征。结果表明:政府管制会出现“政府失灵”。无法实现政府和水用户之间的激励相容;在完全市场机制配置情况下,由于个人和集体理性的不一致,会导致水资源被过度污染、治污的公共产品提供不足等“市场失灵”,基于不同模式下各自的利与弊,无论哪一种单纯的管理模式都不能满足水资源的可持续发展要求。认为中国水资源管理需要把水量和水质、政府管制与市场机制两种配置方式的优势相结合,提出了一种准市场水权交易机制分析框架。 相似文献
698.
Fan Chun Wai 《中国人口.资源与环境(英文版)》2013,11(4):9-17
Abstract Despite the adverse impact of the budget deficit in Hong Kong has been alleviated since the economic recovery from 2003, the fiscal deficit may return when there is another downturn in the economy if the problem is not handled fundamentally. Based on the economic and political situation from 1998 to 2003, the factors that lead to the budget deficit in Hong Kong are analyzed in four perspectives, including (a) increase in public expenditure; (b) decrease in public revenues; (c) poor management of public money and (d) weak administration. With a better understanding on these factors, possible solutions to the fiscal problem faced by the government may be developed. 相似文献
699.
The success of a regulatory regime in decreasing point-source emissions of some harmful chemicals has highlighted the significance
of other sources. A growing number of potentially harmful chemicals have been incorporated into an expanding range of domestic
household products and are sold worldwide. Tighter regulation has been proposed, and the European Commission has introduced
the Regulation on the Registration, Evaluation, and Authorisation of Chemicals to address this concern. However, it is clear
that in addition to the regulation, there is a potential to effect change through retailer and consumer attitudes and behaviours.
Interviews were conducted with 7 key stakeholder groups to identify critical issues, which were then explored using a public
survey questionnaire (1,008 respondents) and 8 subsequent focus groups. The findings demonstrated that the issue of chemicals
in products is of concern to consumers for reasons of personal health rather than environmental protection. Key obstacles
to the wider purchase of “green-alternative” products included perceived high cost and poor performance, lack of availability
of products, and poor information concerning such products. Although improved regulation was seen as part of the solution,
consumers must also play a role. It was clear from this study that consumers are not currently able to make informed choices
about the chemicals they use but that they would be receptive to moving toward a more sustainable use of chemicals in the
future if empowered to do so. 相似文献
700.