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This article proposes an analytical framework for developing indicators of agriculture and rural community sustainability, including the symbiotic relationship between sustainable agriculture and rural well-being. Rural well-being offers a sustainable approach to healthy lifestyles that are based on a balance of many complex components including social, economic, and environmental issues. The United States (US) and the United Kingdom (UK) have taken positions on these issues. The United States Department of Agriculture is ‘committed to helping improve the economy and quality of life in rural America’ through loans and subsidies (USDA 2015). The USDA Sustainable Agriculture Research and Education (SARE) program vision is to sustain ‘an enduring American agriculture of the highest quality that is profitable, protects the nation’s land and water and is a force, providing a healthy and rewarding way of life for farmers and ranchers whose quality products and operations sustain their communities and society’ (SARE 2016; Smart, Sandt and Chris Zdorovtsov 2016). UK government and non-government agencies have taken a more holistic approach to rural well-being in their efforts to achieve a more balanced social–economic–environmental state of rural well-being. The UK interpretation of Community Supported Agriculture is a tested example of this sustainable approach to fostering rural well-being (Saltmarsh et al. 2011).  相似文献   
474.
Fragmentation of the boreal forest by linear features, including seismic lines, has destabilized predator–prey dynamics, resulting in the decline of woodland caribou (Rangifer tarandus caribou) populations. Restoration of human-altered habitat has therefore been identified as a critical management tool for achieving self-sustaining woodland caribou populations. However, only recently has testing of the response of caribou and other wildlife to restoration activities been conducted. Early work has centered around assessing changes in wildlife use of restored seismic lines. We evaluated whether restoration reduces the movement rates of predators and their associated prey, which is expected to decrease predator hunting efficiency and ultimately reduce caribou mortality. We developed a new method for using cameras to measure fine-scale movement by measuring speed as animals traveled between cameras in an array. We used our method to quantify speed of caribou, moose (Alces alces), bears (Ursus americanus), and wolves (Canis lupus) on treated (restored) and untreated seismic lines. Restoration treatments reduced travel speeds along seismic lines of wolves by 1.38 km/h, bears by 0.55 km/h, and caribou by 1.57 km/h, but did not reduce moose travel speeds. Reduced predator and caribou speeds on treated seismic lines are predicted to decrease encounter rates between predators and caribou and thus lower caribou kill rates. However, further work is needed to determine whether reduced movement rates result in reduced encounter rates with prey, and ultimately reduced caribou mortality.  相似文献   
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ABSTRACT

Emissions of carbon monoxide (CO) from motor vehicles cause several hundred accidental fatal poisonings annually in the United States. The circumstances that could lead to fatal poisonings in residential settings with motor vehicles as the source of CO were explored. The risk of death in a garage (volume = 90 m3) and a single-family dwelling (400 m3) was evaluated using a Monte Carlo simulation with varying CO emission rates and ventilation rates. Information on emission rates was obtained from a survey of motor vehicle exhaust gas composition under warm idle conditions in California, and information on ventilation rates was obtained from a summary of published measurements in the U.S. housing stock. The risk of death ranged from 16 to 21% for a 3-hr exposure in a garage to 0% for a 1-hr exposure in a house. Older vehicles were associated with a disproportionately high risk of death. Removing all pre-1975 vehicles from the fleet would reduce the risk of death by one-fourth to two-thirds, depending on the exposure scenario. Significant efforts have been made to control CO emissions from motor vehicles with the goal of reducing CO concentrations in outdoor air. Substantial public health benefit could also be obtained if vehicle control measures were designed to take account of acute CO poisonings explicitly.  相似文献   
476.
Remedial efforts at Superfund sites across the country focus on groundwater contaminant plumes that have been produced by contributions from multiple parties. Allocating cleanup costs between the parties in a fair and equitable manner can be a problem of substantial complexity. Considerable time and money may be spent determining the amount of contamination attributable to each party in order to apportion liability. Contaminant plumes that have evolved over long periods of time may affect large volumes of groundwater and require extensive remediation. Pump and treat remedial costs are driven by both the volume of water extracted and the mass of contaminants removed. Allocation methods based solely on the mass of contaminants contributed by each party are inadequate in this setting since they do not account for both components of the remedial costs. This paper presents an approach for equitably allocating remedial costs when addressing overlapping or commingled groundwater plumes. The method accounts for the major elements driving the costs of remediating dispersed contaminant plumes.  相似文献   
477.
Abstract

In a laboratory study, the persistence of carbofuran and its 3‐hydroxy‐ and 3‐keto‐metabolites was examined separately over 16 wk in sterile and natural organic (muck) and mineral (loam) soils. Carbofuran was relatively persistent in sterile soils; at 8 wk 77% remained in the sterile muck and about 50% remained in the sterile loam. In the natural muck 25% of initial carbofuran remained at 8 wk whereas in the natural loam carbofuran had completely disappeared by that time. The 3‐ketocarbofuran was very short‐lived even in the sterile muck where only 50% remained at 1 wk. The 3‐hydroxycarbofuran degraded appreciably on zero day in the natural soils (with conversion to 3‐ketocarbofuran) and about 90% had disappeared in 1 wk. A more detailed study of the persistence of 3‐hydroxycarbofuran in the natural soils showed complete disappearance in 2 days in loam and in 3 days in muck. The 3‐ketocarbofuran produced from the 3‐hydroxy‐carbofuran reached a maximum concentration in 1 day and then disappeared within 4 days in loam and about 1 wk in muck.  相似文献   
478.
Abstract

The stability of dieldrin, aldrin, lindane, chlorpyrifos and prothiofos was determined in distilled water and in roof water from either galvanised or concrete tanks. Samples were stored in the dark at 23°C. Dieldrin and lindane were stable for the 36 week period. Aldrin dissipated rapidly with a half‐life of 4–5 weeks, with no dieldrin being formed. Chlorpyrifos and prothiofos also broke down, with half‐lives ranging 12–18 weeks and 11–14 weeks respectively. No significant effect of water type was found. For the purpose of domestic usage, an activated carbon filter would be essential otherwise all contaminated water would have to be disposed of safely.  相似文献   
479.
The scrubbing and pumping actions in the Ejector Venturi Scrubber are two separate phenomenon occurring simultaneously. Each phenomenon requires energy and has efficiency of operation and collection efficiency. These energy and efficiency relationships are discussed and illustrated in form of numerous graphs. The scrubbing energy requirements and how they vary with particle sizes down to one micron are also discussed and presented in form of numerous graphs.  相似文献   
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