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981.
Bushfire fighting is a hazardous occupation and control strategies are generally in place to minimize the hazards. However, little is known regarding firefighters' exposure to bushfire smoke, which is a complex mixture of toxic gases and particles. In Australia, during the prescribed burning season, firefighters are likely to be exposed on a regular basis to bushfire smoke, but whether these exposures affect health has yet to be determined. There are a number of factors that govern whether exposure to smoke will result in short-term and/or long-term health problems, including the concentrations of air pollutants within the breathing zone of the firefighter, the exposure duration, and health susceptibility of the individual, especially for pre-existing lung or heart disease. This paper presents measurements of firefighters' personal exposure to bushfire smoke, the first step within a risk management framework. It provides crucial information on the magnitude, extent and frequency of personal exposure to bushfire smoke for a range of typical scenarios. It is found that the primary air toxics of concern are carbon monoxide (CO), respirable particles and formaldehyde. Also, work activity is a major factor influencing exposure with exposure standards (both average and short-term limits) likely to be exceeded for activities such as suppression of spot fires, holding the fireline, and patrolling at the edge of a burn area in the urban-rural interface.  相似文献   
982.
We argue that the environment, broadly construed, has a profound effect on human cognition, action, and well-being. If this is true, then the field of environmental psychology has a far larger potential to aid humanity than is generally realized. We suggest that the field would be more likely to achieve this potential if it viewed environments from the perspective of human informational needs, and focused on environmental/informational patterns that have the potential to make it easier for people to help themselves. Further, achieving such benefits could be greatly enhanced by taking advantage of the many opportunities available for collaborating with researchers in other areas of psychology. The reasonable person model is offered as a perspective that could facilitate moving in these various new directions while taking advantage of the considerable existent knowledge about human–environment interactions that is currently underappreciated.  相似文献   
983.
The measurement of travel costs in recreational demand modeling has been a contentious issue for many decades. This article explores the use of a number of alternative methods of incorporating time costs in the travel cost modeling process. Travel cost values where the opportunity cost of time is excluded, where it is included as a percentage of the individual's reported wage rate and where it based on an estimated wage from a secondary data source (the European Community Household Panel) are compared and then used in a conditional logit model to estimate the demand for whitewater kayaking in Ireland. We then evaluate the effect of different treatments of the cost of travel time on the welfare impacts of a number of different management scenarios for kayaking rivers in Ireland, and find that statistically significant differences emerge.  相似文献   
984.
Advancing the understanding of spatiotemporal aspects of air pollution in the urban environment is an area where improved methods can be of great benefit to exposure assessment and policy support. This paper explores the potential of a technique known as kriging with external drift (KED) to provide high resolution maps of fine particulate matter for a downtown region of Cusco, Peru. There were three stages in this research. The first was to conduct a pilot level monitoring campaign to investigate ambient, regional, and street-level air pollutant concentrations for particulate matter (PM2.5, PM10) and carbon monoxide (CO) in the Province of Cusco. The second was to compile observations within a geographic information system (GIS) in order to characterize the proximal effect of the local transportation network, elevation, and land use classifications on PM2.5. Third, regression, ordinary kriging and kriging with external drift were used to model PM2.5 for three select time periods during a 24-h day. Statistical evaluations indicate kriging with external drift resulted in the strongest models explaining 64% of variability seen with morning particle concentrations, 25% for afternoon particles, and 53% in evening particles. These models capture spatial and temporal variability for air pollution in Cusco. These variations seem to be influenced, to varying degrees, by elevation, meteorological conditions, spatial location, and transportation characteristics. In conclusion, combining GIS, meteorological data and geostatistics proved to be a complementary suite of tools for incorporating spatiotemporal analysis into the air quality assessment.  相似文献   
985.
Global climate change, along with continued habitat loss and fragmentation, is now recognized as being a major threat to future biodiversity. There is a very real threat to species, arising from the need to shift their ranges in the future to track regions of suitable climate. The Important Bird Area (IBA) network is a series of sites designed to conserve avian diversity in the face of current threats from factors such as habitat loss and fragmentation. However, in common with other networks, the IBA network is based on the assumption that the climate will remain unchanged in the future. In this article, we provide a method to simulate the occurrence of species of conservation concern in protected areas, which could be used as a first-step approach to assess the potential impacts of climate change upon such species in protected areas. We use species-climate response surface models to relate the occurrence of 12 biome-restricted African species to climate data at a coarse (quarter degree-degree latitude-longitude) resolution and then intersect the grid model output with IBA outlines to simulate the occurrence of the species in South African IBAs. Our results demonstrate that this relatively simple technique provides good simulations of current species' occurrence in protected areas. We then use basic habitat data for IBAs along with habitat preference data for the species to reduce over-prediction and further improve predictive ability. This approach can be used with future climate change scenarios to highlight vulnerable species in IBAs in the future and allow practical recommendations to be made to enhance the IBA network and minimize the predicted impacts of climate change.  相似文献   
986.
A method was developed to score the ecological condition of first- to third-order stream reaches in the Auckland region of New Zealand based on the performance of their key ecological functions. Such a method is required by consultants and resource managers to quantify the reduction in ecological condition of a modified stream reach relative to its unmodified state. This is a fundamental precursor for the determination of fair environmental compensation for achieving no-net-loss in overall stream ecological value. Field testing and subsequent use of the method indicated that it provides a useful measure of ecological condition related to the performance of stream ecological functions. It is relatively simple to apply compared to a full ecological study, is quick to use, and allows identification of the degree of impairment of each of the key ecological functions. The scoring system was designed so that future improvements in the measurement of stream functions can be incorporated into it. Although the methodology was specifically designed for Auckland streams, the principles can be readily adapted to other regions and stream types.  相似文献   
987.
Transformation toward a sustainable future requires an earth stewardship approach to shift society from its current goal of increasing material wealth to a vision of sustaining built, natural, human, and social capital—equitably distributed across society, within and among nations. Widespread concern about earth’s current trajectory and support for actions that would foster more sustainable pathways suggests potential social tipping points in public demand for an earth stewardship vision. Here, we draw on empirical studies and theory to show that movement toward a stewardship vision can be facilitated by changes in either policy incentives or social norms. Our novel contribution is to point out that both norms and incentives must change and can do so interactively. This can be facilitated through leverage points and complementarities across policy areas, based on values, system design, and agency. Potential catalysts include novel democratic institutions and engagement of non-governmental actors, such as businesses, civic leaders, and social movements as agents for redistribution of power. Because no single intervention will transform the world, a key challenge is to align actions to be synergistic, persistent, and scalable.  相似文献   
988.
A scientifically valid accuracy assessment of a large-area, land-cover map is expensive. Environmental monitoring programs offer a potential source of data to partially defray the cost of accuracy assessment while still maintaining the statistical validity. In this article, three general strategies for combining accuracy assessment and environmental monitoring protocols are described. These strategies range from a fully integrated accuracy assessment and environmental monitoring protocol, to one in which the protocols operate nearly independently. For all three strategies, features critical to using monitoring data for accuracy assessment include compatibility of the land-cover classification schemes, precisely co-registered sample data, and spatial and temporal compatibility of the map and reference data. Two monitoring programs, the National Resources Inventory (NRI) and the Forest Inventory and Monitoring (FIM), are used to illustrate important features for implementing a combined protocol.  相似文献   
989.
Evaluating the overall environmental health of a region invariably involves using databases from multiple organizations. Several approaches to deal with the related technological and sociological issues have been used by various programs. Flexible data systems are required to deal with rapid changes in technology, the social and political climate for sharing and integrating data, and expectations of diverse users. Here we describe how the Environmental Monitoring and Assessment Program and the Chesapeake Bay Program manage their data for regional studies. These programs, which encompass areas of different geographic scales but face similar issues, have adopted some solutions in common, but also have tried some unique solutions suited to their needs. Understanding the tribulations and successes of these programs may help others attempting similar assessments. Both these programs have embraced distributed data systems that are managed by the organizations owning them. Both use common guidelines and policies that assure consistency and quality of data and information. These principles and tools comprise a flexible, sustainable approach that meets modern challenges of data management.  相似文献   
990.
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