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31.
Sand and dust storms (SDS) are wind erosion events typically associated with dryland regions, although they can occur in most environments and their impacts are frequently experienced outside drylands because desert dust haze often is transported great distances. SDS represent hazards to society in numerous ways, yet they do not feature prominently in the disasters literature. This paper considers SDS in a hazard context by examining their ramifications in economic, physical, and social terms, with a focus on agriculture, health, transport, utilities, households, and the commercial and manufacturing sector. There are few assessments of the economic consequences of SDS and those studies that have been conducted lack consistency in data collection methods and analysis. SDS do not result in the significant damage to infrastructure usually associated with many disasters, but the cumulative effects on society can be significant because SDS occur more commonly than most other types of natural hazard.  相似文献   
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The objective of this research was to modify an extended detention basin to provide batch treatment of stormwater runoff. An automated valve/controller was developed and placed on the outlet of a detention basin in Austin, Texas, which allowed the water quality volume to be retained in the basin for a preset length of time. The influent and effluent of the modified basin were monitored for total suspended solids (TSS), nutrients, chemical oxygen demand (COD), and total and dissolved metals. Statistically significant removal of total metals, COD, total nitrogen, total phosphorus, and TSS was observed, with a discharge event mean TSS concentration of 7 mg/L and a TSS removal efficiency of 91%. The modified basin has substantially better pollutant removal than conventional extended detention basins and is comparable with that of Austin sand filters, which are a common structural stormwater treatment system in the Austin area. The valve also can be used to isolate hazardous material spills.  相似文献   
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The Denver Air Quality Modeling Study (DAQMS) is a comprehensive modeling effort originally undertaken to apportion sources of visibility degradation and examine the visibility benefits of future emission strategies in the Denver metropolitan area. Because of the detailed treatment of the chemical and physical processes and high temporal, vertical, and horizontal resolution of the system, it is possible to examine other air-related issues and their relationships to visibility. The DAQMS analysis system consists of the Denver Air Quality Model (DAQM), a three-dimensional Eulerian chemical-transport model including aerosol and gas-phase transport and transformation processes, a three-dimensional mesoscale meteorological modeling system, visibility analysis procedures, and an emissions processing system. DAQM, the meteorological model, and the emissions information operate on a domain covering approximately the entire state of Colorado with 8-km grid resolution and 15 vertical levels from the surface to the stratosphere. Analysis from a winter visibility episode illustrates the differences between spatial and temporal distributions of light extinction, fine and coarse particle aerosol concentrations, oxidants, and carbon monoxide under various emission scenarios. Studies aimed at exploring interrelationships between these air quality concerns for different seasons, meteorological conditions, and emission management scenarios are outlined.  相似文献   
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The prey naivety hypothesis posits that prey are vulnerable to introduced predators because many generations in slow gradual coevolution are needed for appropriate avoidance responses to develop. It predicts that prey will be more responsive to native than introduced predators and less responsive to introduced predators that differ substantially from native predators and from those newly established. To test these predictions, we conducted a global meta-analysis of studies that measured the wariness responses of small mammals to the scent of sympatric mammalian mesopredators. We identified 26 studies that met our selection criteria. These studies comprised 134 experiments reporting on the responses of 36 small mammal species to the scent of six introduced mesopredators and 12 native mesopredators. For each introduced mesopredator, we measured their phylogenetic and functional distance to local native mesopredators and the number of years sympatric with their prey. We used predator and prey body mass as a measure of predation risk. Globally, small mammals were similarly wary of the scent of native and introduced mesopredators; phylogenetic and functional distance between introduced mesopredators and closest native mesopredators had no effect on wariness; and wariness was unrelated to the number of prey generations, or years, since first contact with introduced mesopredators. Small mammal wariness was associated with predator-prey body mass ratio, regardless of the nativity. The one thing animals do not seem to recognize is whether their predators are native.  相似文献   
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This article describes the increasing connections between the fields of Indigenous studies and environmental management and examines some of the ways that an Indigenous studies perspective can guide thinking about environmental management. Indigenous groups have been involved in the management of environmental and natural resources on their lands since time immemorial. Indigenous groups have also become increasingly involved in Western practices of environmental management with the advent of co-management institutions, subsistence boards, traditional ecological knowledge forums, and environmental issues affecting Indigenous resources. Thus, it is an important time for scholarship that explores how Indigenous groups are both shaping and being affected by processes of environmental management. This article summarizes key findings and themes from eight papers situated at the intersection of these two fields of study and identify means by which environmental managers can better accommodate Indigenous rights and perspectives. It is the authors’ hope that increased dialog between Indigenous studies and environmental management can contribute to the building of sustainable and socially just environmental management practices.  相似文献   
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Background  Exposure to harmful levels of ultraviolet-B radiation (UVB), a component of solar radiation, has been suggested as a potential cause of amphibian declines. Methods  We measured solar radiation (UVB, ultraviolet-A, and visible) wavebands in breeding ponds of Bufo boreas (boreal toad, a montane species that has undergone severe population declines) and Bufo woodhousii (Woodhouse’s toad, a plains toad that has not experienced declines) and examined tolerances of these species to simulated solar UVB exposures in the laboratory. Results  We found larvae of both species to be tolerant of simulated solar UVB in excess of solar UVB levels observed in their breeding ponds. B. boreas tadpoles were more tolerant of simulated solar UVB exposure than B. woodhousii tadpoles, possibly because of greater amounts of photoprotective melanin in B. boreas skin. Conclusions  UVB levels observed in B. boreas habitats do not currently appear to constitute a threat to the survival of these animals; however, long-term (>1 month) exposure to UVB levels comparable to levels associated with the water interface appears to reduce survival in B. woodhousii tadpoles. Therefore, future increases in surface and water column UVB radiation in bufonid habitats might pose significant survival risks to B. boreas or B. woodhousii populations.  相似文献   
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One of the major challenges facing the world today is defining paths to sustainable futures. Part of the challenge is developing a national energy strategy that promotes an adequate energy supply for the United States, while enhancing environmental quality and maintaining U.S. competitiveness in the world economy. To assist in this challenge, we have developed a screening technique to analyze the effectiveness of different proposed emissions reduction strategies. The technique, referred to as the visibility assessment screening technique (VAST), is designed to examine possible impacts on visibility of emission changes of sulfur oxides, nitrogen oxides, volatile organic compounds (i.e., SO2, NOx, and VOC) and fine and coarse particulate matter (PM). The influence of relative humidity, natural aerosols, and the chemical interconnections among sulfur and nitrogen components of aerosols in determining the effectiveness of Clean Air Act Amendment and other projected energy-related emissions changes on eastern and western visibility are explored. The effectiveness of these strategies on particulate matter impacts and potentially on ozone is also noted.  相似文献   
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Environment, Development and Sustainability - This paper examines higher education efforts linking United Nations Sustainable Development Goals (UNSDGs) and agri-food system sustainability given...  相似文献   
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