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821.
This article details a case study of a voluntary, decentralized institutional arrangement for nonpint source water pollution control used in the Root River watershed in southeastern Wisconsin. This watershed was chosen because of its mix of urban, agricultural, and urbanizing land uses. The project objectives were to monitor and draw conclusions about the effectiveness of a voluntary, decentralized institutional system, to specify deficiencies of the approach and suggest means to correct them, and to use the conclusions to speculate about the need for regulations regarding nonpoint source pollution control or the appropriateness of financial incentives for nonpoint source control. Institutional factors considered include diversity of land uses in the watershed, educational needs, economic conditions, personality, water quality, number of agencies involved, definition of authority, and bureaucratic requirements  相似文献   
822.
823.
Remediation of contaminated land and groundwater is of common international concern. The context and approach taken to the problem are, however, country-specific. A survey of remedial activity occurring within England and Wales over the period 1996-1999 was commissioned by the Environment Agency (for England and Wales) to establish a baseline against which future trends in remedial activity could be judged. This paper: explains the context of contaminated land and groundwater remediation in England and Wales (Britain); provides an overview of the 1996-1999 survey of remedial activity, discussing its findings within its legislative and institutional context; and, discusses the survey results of significance to the management of contaminated land and groundwater internationally. The survey obtained specific data from 367 remediated sites supplemented by general data from a further 1189 contaminated (not necessarily remediated) sites. The survey aimed to be, and was indicative of remediation practice, and did not seek to identify every remediation scheme operating. Previous anecdotal evidences were generally confirmed. Civil engineering-based techniques dominated and were used at 94% of sites with in situ techniques (predominantly vapour extraction-based) on 16% and ex situ on just 5%. Although disposal to landfill was dominant and occurred at over 80% of sites, integrated use of multiple techniques was common. Remediation was predominantly of soil (rather than water), development-based, designed to protect human health and reflected national development-led and 'suitable for use' policies. Lessons of international relevance from the survey and general British experience are drawn concerning remediation technique selection, regulatory and financial support of innovative remediation techniques and demonstration sites, competent use of risk-based approaches to allow pragmatic remediation and effective use of quality guidelines, need for effective guidance to highlight water quality issues, the necessity of post remediation monitoring to prove remediation effectiveness and the keeping of remediation databases.  相似文献   
824.
The impact of urbanization on timber harvesting in the south central United States was investigated. Geo-referenced Census and Forest Inventory Analysis (FIA) data were combined using a geographic information system (GIS) in order to examine the effects of various demographic and biophysical forest inventory characteristics on timber harvesting. These effects were estimated for intermediate and final harvests using a multinomial logit model. The probability for both types of harvests decreased with increasing population density, decreasing forest size, and decreasing distance to urban areas; however, the reduction in intermediate harvests was greater for each variable. Harvesting rates decreased by as much as 19% as population densities increased or distance to urban areas decreased. The results indicated that active forest management is curtailed far beyond the urban boundary. In order to model the impact of urbanization adequately, timber supply projections must also account for its impact on harvesting frequencies in surrounding areas.  相似文献   
825.
Environmental risk assessment and the intrusion of bias   总被引:1,自引:0,他引:1  
The concept of managing the environment and any associated human health impacts by means of such science-based tools as toxicological evaluation, risk assessment, and economic appraisal has become widely accepted in professional circles. These increasingly complex methodologies have not won universal support, however, even among the technically minded, and the wider public has in many cases remained sceptical. The public's seeming lack of enthusiasm has frequently been assigned to ignorance of science, irrationality even, and some attempts have been made to ameliorate the situation by means of education, though with little evidence of success. However, this review advances an alternative explanation, namely, that the disenchantment has more to do with procedural than technical matters. Many issues, although treated with technical risk assessment appear to have forced themselves onto the agenda because of factors only passingly connected with risk, and which are more related to the intrusion of disputed values and other sources of bias. This paper also notes that the intervention of bias in decision making is rife, and is found as much in professional as in public approaches. This need not itself be a problem, providing it is recognised and openly expressed. However, there remains a need for much greater circumspection and frankness by professions about the status of their art, and a determined effort if the full social benefits of environmental risk assessment (ERA) are to be realised.  相似文献   
826.
Community involvement has been identified as an important factor in the successful redevelopment of contaminated land, and access to technical resources has been a barrier for some communities. This paper describes how the US Environmental Protection Agency funded Technical Outreach Services to Communities programme was used to support four communities involved in land revitalization. The four New England case studies were used to retrospectively draw lessons learned that could be useful to others interested in similar community work. We suggest that the broad lessons point to four factors for success, namely, where there is: (1) a common vision in the community; (2) a cohesive community; (3) an opportunity for co-learning; and (4) a commitment among the parties for long-term engagement. We conclude that technical support can serve as a useful framework for developing trustful and long-term relationships with communities.  相似文献   
827.
This article chronicles activities and approaches carried out in working with community partners and public and private stakeholders in advancing revitalization within Bridgeport, CT. The approach described utilizes brownfields redevelopment as a focal point for a stakeholder process whose goal is neighbourhood revitalization. Two neighbourhoods—the Went End and East End—are the focus for major stakeholder-driven brownfields redevelopment processes. The article defines key elements of the stakeholder process including: involvement at several levels from neighbours to the site to the Mayor's office and beyond, a risk communication process that incorporates the broad concerns of the stakeholders including crime and violence, and the need for ongoing oversight and management throughout the redevelopment process.  相似文献   
828.
Several writers on animal ethics defend the abolition of most or all animal agriculture, which they consider an unethical exploitation of sentient non-human animals. However, animal agriculture can also be seen as a co-evolution over thousands of years, that has affected biology and behavior on the one hand, and quality of life of humans and domestic animals on the other. Furthermore, animals are important in sustainable agriculture. They can increase efficiency by their ability to transform materials unsuitable for human consumption and by grazing areas that would be difficult to harvest otherwise. Grazing of natural pastures is essential for the pastoral landscape, an important habitat for wild flora and fauna and much valued by humans for its aesthetic value. Thus it seems that the environment gains substantially when animals are included in sustainable agricultural systems. But what about the animals themselves? Objections against animal agriculture often refer to the disrespect for animals’ lives, integrity, and welfare in present intensive animal production systems. Of the three issues at stake, neither integrity nor animal welfare need in principle be violated in carefully designed animal husbandry systems. The main ethical conflict seems to lie in the killing of animals, which is inevitable if the system is to deliver animal products. In this paper, we present the benefits and costs to humans and animals of including animals in sustainable agriculture, and discuss how to address some of the ethical issues involved.  相似文献   
829.
As employees find themselves in geographically separated teams, the loss of face‐to‐face interaction has led to the development of new monitoring technologies that provide availability information for enhancing collaboration. Drawing on diverse literatures in electronic performance monitoring, computer supported cooperative work, privacy, and fairness, a comprehensive theoretical model of monitoring acceptance was developed to examine the effects of being monitored for availability. In the first study, over 600 employees from a large number of organizations responded to one of a variety of monitoring system characteristics. Although the model found strong support overall, results suggest that technical solutions, such as manipulating the characteristics of the awareness system, are not sufficient to ensure fairness and privacy. A second, focus group study, adds support for the theoretical model and provides an explanation for these quantitative results concerning system characteristics. Specifically, the qualitative evidence suggests that these systems can invade employees' psychological barriers ‐ and thus manipulating the technology will only have small effects on fairness and privacy because the technology has already crossed the line from benign to invasive. The paper concludes by presenting theoretical and practical implications for the consideration of psychological boundaries in the design and use of ubiquitous monitoring and communication technologies. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
830.
Across the United Kingdom, the majority of local authoritieshave now completed their first phase of local air qualityreview and assessment work, as required under the AirQuality Strategy for England, Scotland, Wales and NorthernIreland (DETR, 2000a). Emerging from this first phasework is an anticipated suite of over 110 Air QualityManagement Areas (AQMAs). These areas are identifiedlocations where one or more of the national air qualityobjectives are predicted to exceed by specific target dates,and their spatial extent and shape is emerging as highlyvariable. Local authorities are guided to use a variety ofscientific tools to underpin the scientific assessments, anda consideration of uncertainty in both the tools used andsubsequent delineation of AQMAs is likely to affect theemerging management areas significantly. With subsidiarity underpinning the process of local air qualitymanagement (LAQM), local decision-making is anticipated toinfluence the outcome of the LAQM process in its entirety,with the declaration of AQMAs necessitating the preparationand implementation of air quality action plans. UKexperience of the effective management of local air quality,through the designation of AQMAs, demonstrates a valuableframework for other European countries developing mechanismsto manage air quality locally.  相似文献   
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