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91.
Christine E. Wilkinson Alex McInturff Jennifer R. B. Miller Veronica Yovovich Kaitlyn M. Gaynor Kendall Calhoun Harshad Karandikar Jeff Vance Martin Phoebe Parker-Shames Avery Shawler Amy Van Scoyoc Justin S. Brashares 《Conservation biology》2020,34(4):854-867
Carnivore predation on livestock is a complex management and policy challenge, yet it is also intrinsically an ecological interaction between predators and prey. Human–wildlife interactions occur in socioecological systems in which human and environmental processes are closely linked. However, underlying human–wildlife conflict and key to unpacking its complexity are concrete and identifiable ecological mechanisms that lead to predation events. To better understand how ecological theory accords with interactions between wild predators and domestic prey, we developed a framework to describe ecological drivers of predation on livestock. We based this framework on foundational ecological theory and current research on interactions between predators and domestic prey. We used this framework to examine ecological mechanisms (e.g., density-mediated effects, behaviorally mediated effects, and optimal foraging theory) through which specific management interventions operate, and we analyzed the ecological determinants of failure and success of management interventions in 3 case studies: snow leopards (Panthera uncia), wolves (Canis lupus), and cougars (Puma concolor). The varied, context-dependent successes and failures of the management interventions in these case studies demonstrated the utility of using an ecological framework to ground research and management of carnivore–livestock conflict. Mitigation of human–wildlife conflict appears to require an understanding of how fundamental ecological theories work within domestic predator–prey systems. 相似文献
92.
93.
Alfred J. Vella Alex Camilleri Jean Pierre Tabone Adami 《Environmental geochemistry and health》1996,18(4):165-170
The concentration of sulphate on limestone surfaces of the external walls of churches in Malta is shown to be related to their position and distance from a power station, the main local point source of sulphur dioxide pollution. Limestone powder collected from these surfaces was examined for the presence of particles which, under low-power optical microscopy, appear as shiny black amorphous bodies which were interpreted as soot particles; the abundance of these bodies was expressed as a black particle count (BPC). The degree of sulphation and BPC were shown to be correlated with each other and both appeared to be strongly dependent on the prevailing wind. The BPC contour map indicated an important contribution to the parameter from vehicular traffic. It is suggested that the degree of sulphation and BPC of limestone surfaces from the built environment should function as environmental indicators of the relative air quality with respect to SO2 and soot pollution. This data is possibly more accurately representative of the relative long-term air-quality status of different areas of habitation than that deduced from single or episodic measurements of atmospheric pollutant levels. 相似文献
94.
A hybrid process for manufacturing surgical-grade knife blade cutting edges from bulk metallic glass
Alex J. Krejcie Shiv G. Kapoor Richard E. DeVor 《Journal of Manufacturing Processes》2012,14(1):26-34
The demand for precision surgical knives is enormous. Currently, diamond knives have been the preferred choice among surgeons for use in precision surgeries, owing to the extreme hardness of diamond and the sharpness that can be achieved in single crystal diamond blades, but material and processing costs are high. Bulk metallic glass (BMG) has the potential to be an economically viable material of similar performance for use in precision surgical knives. To this end, a novel hybrid manufacturing process integrating thermally assisted micro-molding and micro-drawing has been developed for producing BMG surgical-grade knife blade cutting edges with edge radii <50 nm. A hybrid process testbed was designed and used to successfully run tests over a range of the key process variables. Through this testing the deformation of BMG under different strain rates and temperatures was studied in terms of the quality of edge formation. The hybrid process was shown to be capable of producing cutting edges of radius at or below 100 nm. 相似文献
95.
The primary objective of this paper is to describe the impact of national seat belt enforcement mobilizations in terms of changes in public awareness, perceptions, and opinions as they relate to Operation ABC (Always Buckle Up). In order to monitor changes in public awareness and perceptions, a number of national telephone surveys were conducted. Survey results indicated that the following characteristics were associated with lower self-reported seat belt use rates: (a) males; (b) 18-34 age group; (c) persons with lower income; (d) persons with lower education; (e) persons living in rural areas; (f) residents of the Northeast, Midwest, and Great Lakes; (g) residents of states with secondary enforcement laws; and (h) persons less likely to read a newspaper and more likely to listen to the radio. Telephone surveys also suggested that the following groups are more likely to fail to properly secure a child under 12: (a) persons who say they have problems securing a child in seat belt; (b) farm belt residents; (c) Hispanic and Latinos; (d) persons who indicate that they always wear a seat belt but indicate they have not in the past month; (e) persons with older vehicles; (f) lower income respondents; (g) residents of the Deep South; (h) internet non-users; and (i) urban men. These findings provide support for some basic guidelines and suggestions for conducting seat belt enforcement activities. 相似文献
96.
利用MEGAN模式估算了珠三角地区2006年异戊二烯的排放情况,并设计了两组敏感性实验深入探讨了气象模拟误差对异戊二烯排放的影响.估算结果显示,2006年珠三角地区异戊二烯的排放量为95.56×106kg(以C计),且主要分布在珠三角地区周边植被覆盖较高的地方;受气象条件季节变化的影响,异戊二烯的排放表现出显著的季节和日变化特征,最大异戊二烯排放通量季节出现在夏季,为0.920t·km-2(以C计),最大排放速率均出现在13:00.敏感性实验结果显示,气象模拟误差能显著影响异戊二烯的排放,升高(降低)太阳辐射的输入,异戊二烯的排放量增加(减小)36.20%~50.70%(30.73%~41.88%),大于温度改变引起的排放量变化;升高(降低)气象输入并不会改变异戊二烯排放的日变化特征,但能显著影响排放速率的大小.上午8:00或下午17:00,异戊二烯排放速率的改变最为明显. 相似文献
97.
Alex Y. Lo 《Journal of Environmental Policy & Planning》2016,18(1):27-46
The changing political environment in Hong Kong is likely to accelerate the transition in environmental policy discourse. Opportunities for critical public involvement are increasing and new environmental discourses are emerging. Yet, previous social surveys did not explore the range of these discourses and few focused on climate change. The paper outlines the public discourses of climate change in Hong Kong. Using Q-methodology, four distinctive discourses were identified, namely Pure Environmentalism, Political Pragmatism, Popular Optimism, and Fair Rationalism. While the first one is climate-centric, the other three are political or social in nature and do not indicate a clear or coherent climate orientation. This suggests that the climate change concern of the Hong Kong public is not tightly embedded into a coherent narrative of social and institutional transformation. Effective climate change governance and policies require strengthening the link between such concern and the public desires for social and institutional transformation. Bringing together the ongoing social movements and environmental campaigns will be instrumental to nurture an active climate citizenry. 相似文献
98.
Alex Steele 《The Environmentalist》1991,11(3):195-212
Summary This paper measures the diversity of environmental impacts inherent within a proposal by the Central Electricity Generating Board (CEGB) to build a demonstration wind farm at Langdon Common in the North Pennines, UK. This assessment was made in April, 1989 in the wake of the European Community Directive on Environmental Impact Assessment (EIA) and its subsequent interpretation within the UK Town and Country Planning (Assessment of Environmental Effects) Regulations (1988).Langdon Common lies within an Area of Outstanding Natural Beauty (AONB) and within a Site of Special Scientific Interest (SSSI). These designations create a contentious choice of site made by the CEGB and the extent of environmental impact is subsequently made more broad. While the conclusions drawn are specific to Langdon Common, the methodology evolved within the project lends itself to further application to other sites in the future. The following Environmental Impact Assessment can, therefore, be seen as a step towards the reconciliation of the acceptable siting of wind turbines in the UK and the capacity of the planning system to regulate such development.This paper by Alex Steele received the Institution of Environmental Sciences award and First Prize for the best undergraduate environmental project in the UK in 1989. Alex Steele graduated from Sunderland Polytechnic in that year and now works as an Environmental Planner for a leading company of Environmental Management Consultants. 相似文献
99.
100.
Marie Briguglio Liam Delaney Alex Wood 《Journal of Environmental Planning and Management》2016,59(10):1751-1774
This paper assesses the determinants of take-up of a voluntary waste separation scheme, in a scenario where residents sorted, stored and paid for collection of recycling waste even though mixed waste was collected at the kerbside more conveniently, free of charge and without any quantity limits. Uptake of the scheme was positive, persistent and diverse across localities, offering an opportunity to assess the factors determining voluntary participation in the presence of disincentives. We employ a unique panel data-set (n = 4,644) from Malta, including data on recyclable waste kilogrammes collected over the first 86 weeks of the scheme's operation. Drawing on insights from environmental economics and psychology, a model is empirically estimated. Results indicate that uptake is suppressed by the initial constraints households may face and stimulated by collection frequency. Political vote is an important determinant of participation and this interacts with scheme promotion to create diverse uptake rates. 相似文献