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61.
Social conscience and public opinion have promoted a popular belief that all recycling is good for the environment. Planning policies and environmental legislation have been and continue to be influenced in part by this belief. Economic and political factors have been important especially in terms of developing recovery programmes and systems for collecting waste material. This is particularly true for paper products, for which there is now a whole range of arbitrary set recycling targets in most western countries. Paper products are different from all other major recycled products in that they are made from a renewable resource and, as recovered waste, it has alternative uses such as energy recovery. In the framework of mounting empirical evidence the aim of the paper is to question the validity of social conscience as a raison d'etre for increasing the rate of recycling paper products. Forests, which are the primary renewable resource, have important implications for a whole range of economic, social and climatic issues, especially global warming. There is an urgent need to take stock of these issues for both planning and managing the environment.  相似文献   
62.
Preface     
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63.
Woody encroachment is a widespread and acute phenomenon affecting grasslands and savannas worldwide. We performed a meta-analysis of 29 studies from 13 different grassland/savanna communities in North America to determine the consequences of woody encroachment on plant species richness. In all 13 communities, species richness declined with woody plant encroachment (average decline = 45%). Species richness declined more in communities with higher precipitation (r2 = 0.81) and where encroachment was associated with a greater change in annual net primary productivity (ANPP; r2 = 0.69). Based on the strong positive correlation between precipitation and ANPP following encroachment (r2 = 0.87), we hypothesize that these relationships occur because water-limited woody plants experience a greater physiological and demographic release as precipitation increases. The observed relationship between species richness and ANPP provides support for the theoretical expectation that a trade-off occurs between richness and productivity in herbaceous communities. We conclude that woody plant encroachment leads to significant declines in species richness in North American grassland/savanna communities.  相似文献   
64.
In 2009, the Sustainable Remediation Forum released a white paper entitled “Integrating sustainable principles, practices, and metrics into remediation projects” (Ellis & Hadley, 2009, Remediation, 19, pp. 5–114). Sustainable remediation was a relatively new concept, and the white paper explored a range of approaches on how sustainability could be integrated into traditional remediation projects. This paper revisits the 2009 white paper, providing an overview of the early days of the evolving sustainable remediation practice and an assessment of the progress of sustainable remediation over the last 10 years with a primary focus on the United States. The current state of the sustainable remediation practice includes published literature, current practices and resources, applications, room for improvement, international progress, the virtuous cycle that applying sustainable remediation creates, and the status of the objectives cited in the 2009 white paper. Over the last decade, several sustainable remediation frontiers have emerged that will likely be a focus in advancing the practice. These frontiers include climate change and resiliency, weighting and valuation to help better consolidate different sustainable remediation metrics, programmatic implementation, and better integration of the societal impacts of sustainable remediation. Finally, as was the case for the 2009 white paper, this paper explores how sustainable remediation may evolve over the next 10 years and focuses on the events and drivers that can be significant in the pace of further development of the practice. The events and drivers include transformation impacts, societal influences, and the continued development of new technologies, approaches, and tools by remediation practitioners. The remediation industry has made significant progress in developing the practice of sustainable remediation and has implemented it successfully into hundreds of projects. While progress has been significant, an opportunity exists to implement the tenets of sustainable remediation on many more projects and explore new frontiers to help improve the communication, integration, and derived benefits from implementing sustainable remediation into future remediation projects.  相似文献   
65.
Regional Environmental Change - This article outlines a conceptual model and comparatively applies it to results from environmental justice (EJ) studies of flood risk in the Miami, Florida, and...  相似文献   
66.
Hispanic residents suffer disproportionately from exposure to toxic pollution hazards, but little is known about why some Hispanic residents live in high-risk neighbourhoods while others are protected from similar risks. This study uses comparative interview-based methods to further understanding of Hispanic people’s residential decision-making and their associated exposures to hazardous air pollutants (HAPs) in the Miami Metropolitan Statistical Area (Florida), which is home to one of the most diverse Hispanic populations in the U.S. We use 22 in-depth interviews conducted with Hispanic householders living at high and low risk to HAPs, selected from a larger representative phone survey of 650 local residents. For Hispanic households at high risk, economic constraints, family ties, desiring a central location, a sense of community, and comfort in a shared culture contributed to their residences in high risk locations. In contrast, protective factors for Hispanic households living at low risk included the desire to live in an ethnically diverse setting, the ease of finding service work, and preferring environmental amenities and exclusivity. Findings demonstrate that there are considerable differences in factors shaping residential decision-making of low- and high-risk Hispanic residents, but that all were influenced by economic, socio-cultural, and environmental considerations to varying degrees.  相似文献   
67.
This article is based on a multimethod study designed to clarify influences on wildfire hazard vulnerability in Arizona’s White Mountains, USA. Findings reveal that multiple factors operating across scales generate socially unequal wildfire risks. At the household scale, conflicting environmental values, reliance on fire insurance and firefighting institutions, a lack of place dependency, and social vulnerability (e.g., a lack of financial, physical, and/or legal capacity to reduce risks) were found to be important influences on wildfire risk. At the regional-scale, the shift from a resource extraction to environmental amenity-based economy has transformed ecological communities, produced unequal social distributions of risks and resources, and shaped people’s social and environmental interactions in everyday life. While working-class locals are more socially vulnerable than amenity migrants to wildfire hazards, they have also been more active in attempting to reduce risks in the aftermath of the disastrous 2002 Rodeo-Chediski fire. Social tensions between locals and amenity migrants temporarily dissolved immediately following the disaster, only to be exacerbated by the heightened perception of risk and the differential commitment to hazard mitigation displayed by these groups over a 2-year study period. Findings suggest that to enhance wildfire safety, environmental managers should acknowledge the environmental benefits associated with hazardous landscapes, the incentives created by risk management programs, and the specific constraints to action for relevant social groups in changing human-environmental context.  相似文献   
68.

Introduction

Heat illness is a leading cause of death and disability among U.S. high school athletes.

Methods

To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009.

Results

During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported.

Conclusions

Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities.

Impact of industry

By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths.  相似文献   
69.
Researchers have noted that current water quality protection strategies, like nutrient management plans, lack a sound hydrological underpinning for pollutant transport processes. This is especially true for areas like the northeastern U.S. where copious research has shown that variable source area hydrology largely governs runoff generation. The goal of this study was to develop a scientifically justified method to identify the locations that generate overland flow. Furthermore, this methodology must be computationally simple enough that it can be utilized or incorporated into nutrient management plans and other established water quality tools. We specifically tested the reliability of the 'distance from a stream,'D(s), and the 'topographic index,'lambda, to predict areas with a high propensity for generating overland flow, i.e. hydrologically sensitive areas (HSA). HSAs were defined by their probability of generating runoff, P(sat), based on 30 year simulations using a physically based hydrological model. Using GIS, each location's P(sat) was correlated with D(s) and lambda. We used three Delaware Co., NY watersheds in the New York City watershed system with areas varying in size from 1.6 to 37 km2 and with forested and agricultural land uses. The topographic index gave stronger, more regionally consistent correlations with P(sat) than did D(s). Equations correlating lambda and P(sat) for each month are presented and can be used to estimate hydrological sensitivity in the region surrounding our study watersheds, i.e. in Delaware Co. This work is currently being incorporated into an Internet Mapping System to facilitate user-friendly, on-line identification of HSAs.  相似文献   
70.
ABSTRACT: About one-third of all West Virginians obtain domestic water from private water wells. In this research, mail and telephone surveys were used to investigate household responses to bacteria, mineral, and organic chemical contamination of domestic water supplies. Of households who were informed of contamination and acknowledged the problem, over 85 percent took action to avoid exposure to water contamination problems. The most common action was to clean and/or repair the water system (55.9 percent of valid surveys). Approximately 45 percent of households made investments of either a water treatment system, a new water source, or correction of contamination source. The average, annual economic cost of rural household actions was $320 for bacteria, $357 for minerals, and $1,090 for organic contamination. These economic costs represent a lower bound estimate for rural household willingness-to-pay (WTP) for a reduction in domestic water contamination from government action. On average, investment actions had lower annual economic costs than noninvestment actions of boiling and hauling water so that households who undertook investment actions in response to water contamination would have a lower WTP for government action to reduce water contamination. When effectiveness of water treatment systems was evaluated, treatment systems which require minimal household maintenance were found to reduce exposure to water contamination to safe levels as households intended when they installed the system. Treatment systems which were commonly ineffective included those which required continual maintenance (e.g., chiorinators) or were not designed to solve the contaminant problem for which they were purchased (e.g., filter systems for bacteria).  相似文献   
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