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101.
This research investigates whether species are perceived differently based on aesthetic and negativistic attitudes, and whether these and other attitudes, naturalistic activities, and gender predict support for the protection of threatened species. 228 undergraduate students completed a survey in which they rated pictures of 10 endangered species on aesthetic and negativistic attitudes, and support for protection. Findings showed that the two-striped garter snake, Ozark big-eared bat, and dolloff cave spider were conceptualized differently than other species, which may be the result of “irrational” fears linked to animal phobias, culture, and emotional reactions to pictures. The regression results support the common belief that aesthetics is an important determinant in perceptions of endangered species and that the importance of negativistic attitudes may be waning. Moralistic worldviews and attitudes toward landowner rights and the Endangered Species Act were significantly related to support for governmental protection of species. Surprisingly, naturalistic activities and gender were not significantly associated with support for governmental protection of species. In general, the results were consistent across both models. However, the amount of variance explained by aesthetic and negativistic attitudes was 23 percent higher in the other species models than in the bat, snake, and spider models. 相似文献
102.
Birds feeding on landfill sites cause problems in terms of nuisance to neighbors, flight safety, a threat to public health,
and affecting the day to day site operation. A number of control measures exist to deter problem species; however, research
into their effectiveness across sites and for multiple species has been limited. We use a modeling approach in order to assess
the effectiveness of nine techniques — pyrotechnics, hand-held distress calls, static distress calls, blank ammunition, a
combination of blank and lethal use of ammunition, the use of falcons, the use of hawks, wailers and helium-filled bird-scaring
kites — at deterring three commonly recorded species — the Black-headed Gull (Larus ridibundus), the Herring Gull (Larus argentatus) and the Lesser Black-backed Gull (Larus fuscus) — from six landfill sites across the United Kingdom. The use of distress calls, falconry, and combinations of lethal and
nonlethal use of ammunition were the most effective techniques for initially deterring birds from these sites. However, when
habituation is considered, there is a clear difference between techniques such as falconry, which have a lethal aspect and
may act to reinforce the deterrence, and the use of techniques such as distress calls, which do not. However there are problems
related to legislation and public perception when lethal techniques are used. 相似文献
103.
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105.
Healthcare waste management continues to present an array of challenges for developing countries, and Botswana is no exception. The possible impact of healthcare waste on public health and the environment has received a lot of attention such that Waste Management dedicated a special issue to the management of healthcare waste (Healthcare Wastes Management, 2005. Waste Management 25(6) 567-665). As the demand for more healthcare facilities increases, there is also an increase on waste generation from these facilities. This situation requires an organised system of healthcare waste management to curb public health risks as well as occupational hazards among healthcare workers as a result of poor waste management. This paper reviews current waste management practices at the healthcare facility level and proposes possible options for improvement in Botswana. 相似文献
106.
PROBLEM: This study assesses the impact of crash and casualty numbers in correspondence to the introduction of mobile speed cameras in the rural county of Norfolk, England. METHOD: Road traffic accident casualty and crash data were collected for two years before the introduction of cameras and two years subsequently. The casualties and crashes occurring at 29 camera sites were identified and separated from those occurring in the rest of the county. Trends in crashes and casualties, and their severity, were examined graphically and comparisons were made between before and after periods. The regression to the mean effect at individual sites was estimated. RESULTS: After the introduction of cameras, overall crashes declined by 1% and crashes involving fatalities or serious injuries declined by 9% on the roads without cameras. At the camera sites, crashes decreased by 19% and fatal and serious crashes by 44%. The reduction in total crashes was significantly greater than that expected from the effect of regression to the mean in 12 out of 20 sites tested. SUMMARY: The introduction of cameras appears to have resulted in real and measurable reductions in crash risk in this rural county. IMPACT ON INDUSTRY: Our results suggest the deployment of mobile speed cameras is an effective tool for organizations wishing to reduce road traffic casualties in areas where high crash rates have been associated with excessive vehicle speeds. 相似文献
107.
Luke A. Halling Benjamin P. Oldroyd Wandee Wattanachaiyingcharoen Andrew B. Barron Piyamas Nanork Siriwat Wongsiri 《Behavioral ecology and sociobiology》2001,49(6):509-513
Apis florea is a single-combed, open-nesting, dwarf honeybee indigenous to Asia. In common with other species of this genus, A. florea is highly polyandrous, and is therefore predicted to curtail worker reproduction by mutual policing mechanisms that keep worker reproduction at an extremely low level. Policing mechanisms could involve destruction of workers' eggs or offspring, or aggression toward those workers that are reproductively active. We show that in A. florea, worker-laid eggs are eliminated approximately twice as fast as queen-laid eggs, indicating that A. florea uses oophagy of worker-laid eggs as a mechanism of worker policing. Genetic analysis of four colonies indicated that all males produced were sons of queens, not workers. Dissections of 800 workers, from four colonies, did not reveal any significant levels of ovary activation. These results suggest that worker policing is an effective component of the mechanisms that maintain worker sterility in this species. Furthermore, they suggest that worker policing via oophagy of worker-laid eggs is pleisiomorphic for the genus. 相似文献
108.
Reproduction in the sea urchin Centrostephanus rodgersii was examined in two types of habitats (“barrens”, i.e. habitats characterised by the high crustose coralline algal cover
typical of urchin-barren grounds, and by the absence of macroalgae; and “fringe”, i.e. habitats characterised by a high macroalgal
biomass and few C. rodgersii) at four locations in New South Wales. The four locations: the Solitary Islands, Sydney, Ulladulla and Eden, span the distribution
of C.␣rodgersii from the subtropics at its northern limit to temperate waters near its southern limit. Histology and estimates of gonad retrieval
rate (GRR) from January 1994 to October 1995 indicated that reproduction was synchronous at all locations. An increase in
the tempo of gametogenesis in May and onset of spawning in June at all locations is consistent with entrainment in response
to exogenous factors. Over the range studied, C. rodgersii experienced relatively similar daylength cycles and contrasting sea-temperature cycles. Short days and lunar conditions coinciding
with the solstice appear likely proximate cues for the onset of spawning. The major difference in reproduction among locations
was in the duration of spawning. In the southern parts of its range breeding occurred over a 5 to 6 mo period, whereas at
the Solitary Islands it lasted ≃1 mo. At most locations the GRRs were significantly higher in the fringe habitat than in the
barrens habitat. The lower reproductive output of urchins in the barrens habitat was attributed to the food-poor conditions
typical of this habitat. The developing fishery for C. rodgersii is likely to be most effective from March to early May. Urchins from barrens areas may not provide sufficient yield to warrant
harvesting.
Received: 29 October 1997 / Accepted: 18 May 1998 相似文献
109.
Managing the integrity of tailings infrastructure is an important aspect of handling mine tailings. Unfortunately, little
research is directed towards its efficient modeling. This paper presents salient aspects of tailings management. It proposes
an integrated geographic information systems (GIS)-based conceptual model for efficient handling of these aspects. The paper
also discusses the various integrated modules and comments on the systematic implementation of the model to achieve desired
results. The modules include: structural integrity management (SIM), release impact assessment (RIA), and hazardous risk assessment
and control (HRAC). 相似文献
110.
Pait AS Whitall DR Dieppa A Newton SE Brune L Caldow C Mason AL Apeti DA Christensen JD 《Environmental monitoring and assessment》2012,184(8):5065-5075
Jobos Bay, located on the southeastern coast of Puerto Rico, contains a variety of habitats including mangroves, seagrass meadows, and coral reefs. The watershed surrounding the bay includes a number of towns, agricultural areas, and the Jobos Bay National Estuarine Research Reserve (NERR). Jobos Bay and the surrounding watershed are part of a Conservation Effects Assessment Project (CEAP), involving the Jobos Bay NERR, the US Department of Agriculture, and the National Oceanic and Atmospheric Administration (NOAA) to assess the benefits of agricultural best management practices (BMPs) on the terrestrial and marine environments. As part of the Jobos Bay CEAP, NOAA collected sediment samples in May 2008 to characterize over 130 organic chemical contaminants. This paper presents the results of the organic contaminant analysis. The organic contaminants detected in the sediments included polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls, and the pesticide DDT. PAHs at one site in the inner bay near a boat yard were significantly elevated; however, all organic contaminant classes measured were below NOAA sediment quality guidelines that would have indicated that impacts were likely. The results of this work provide an important baseline assessment of the marine environment that will assist in understanding the benefits of implementing BMPs on water quality in Jobos Bay. 相似文献