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101.
Perceived status can affect the diffusion of pro-environmental behaviors and sustainable consumption. However, the status of different forms of sustainable consumption has not been adequately explored. Previous studies suggest that curtailment behaviors are associated with low or neutral status, while efficiency behaviors are associated with high status. However, these studies have generally examined a small number of behaviors. Drawing from costly signaling theory, we developed a mixed methods study to explore whether and why pro-environmental behaviors are perceived to be associated with high or low status, the perceived motivation for those behaviors, and the relationship between motivation and status. We conducted structured, interactive interviews with 71 participants to explore perceptions of 19 behaviors. Using quantitative and qualitative analyses, we find that efficiency is rated higher status than curtailment largely due to monetary considerations. Efficiency is also perceived to be motivated by environmental concern to a greater degree than curtailment. Understanding the motivation for behaviors clarifies the social signal because it provides insights into whether one is incurring personal costs. Importantly, it is often unclear whether low-cost curtailment behaviors are adopted by choice rather than financial need. Ambiguity about the intentionality of behaviors results in such behaviors being perceived as lower status. Those who argue that curtailment will be necessary for long-term sustainability must address status perceptions because social stigmas could hinder their adoption. Overcoming such stigmas may require, indicating that curtailment behaviors are voluntary, but it may be more effective to use social or economic mechanisms to increase efficiency behaviors.  相似文献   
102.
Communities who rely directly on the natural environment for their survival typically have developed risk management strategies to enable them to avoid dangerous thresholds of change to their livelihoods. Development policy appropriate for natural resource-based communities requires an understanding of the primary drivers of social-ecological change, the ways in which affected households autonomously respond to such drivers, and the appropriate avenues for intervention to reduce vulnerability. Coffee has been, and still remains, one of the most important commodities of the Mesoamerican region, and hundreds of thousands of smallholder households in the region are dependent in some way on the coffee industry for their livelihood stability. We used the Analytical Network Process to synthesize expert knowledge on the primary drivers of livelihood change in the region as well as the most common household strategies and associated capacities necessary for effective response. The assessment identified both gradual systemic processes as well as specific environmental and market shocks as significant drivers of livelihood change across the region. Agronomic adjustments and new forms of social organization were among the more significant responses of farmers to these changes. The assessment indicates that public interventions in support of adaptation should focus on enhancing farmers’ access to market and technical information and finance, as well as on increasing the viability of farmers’ organizations and cooperatives.  相似文献   
103.
Long JD  Mitchell JL  Sotka EE 《Ecology》2011,92(1):180-188
Intraspecific variation in the strength of inducible plant defenses plays a central role in the interactions between plants and herbivores. Studies of this variation are typically conducted in the greenhouse or laboratory rather than the field. We simultaneously manipulated densities of local consumers in the field within Maine and South Carolina populations of the smooth cordgrass Spartina alterniflora. South Carolina, but not Maine, plants induced resistance when grazed by local consumers. South Carolina populations of Littoraria snails and planthoppers colonized control more than previously grazed South Carolina plants, and Littoraria snails consumed more control than previously grazed plants. The inducible feeding deterrents in South Carolina plants appear to be water soluble, but not phenolic based. In contrast, grazed and control plants from Maine populations did not differ in attractiveness or palatability to Maine consumers. Thus, inducible plant responses by South Carolina plants had a strong effect on the South Carolina consumer community, but no analogous effect occurred in Maine. Field experiments are a powerful approach to detecting the strength of inducible plant resistance and its impacts on local consumers, which in this case were shown to vary with location.  相似文献   
104.
Species that are tolerant of broad environmental gradients may be less vulnerable to epizootic outbreaks of disease. Chytridriomycosis, caused by the fungus Batrachochytrium dendrobatidis, has been linked to extirpations and extinctions of amphibian species in many regions. The pathogen thrives in cool, moist environments, and high amphibian mortality rates have commonly occurred during chytridiomycosis outbreaks in amphibian populations in high-elevation tropical rainforests. In Australia several high-elevation species, including the armored mist frog (Litoria lorica), which is designated as critically endangered by the International Union for the Conservation of Nature (IUCN), were believed to have gone extinct during chytridiomycosis outbreaks in the 1980s and early 1990s. Species with greater elevational ranges disappeared from higher elevations, but remained common in the lowlands. In June 2008, we surveyed a stream in a high-elevation dry sclerophyll forest and discovered a previously unknown population of L. lorica and a population of the waterfall frog (Litoria nannotis). We conducted 6 additional surveys in June 2008, September 2008, March 2009, and August 2009. Prevalences of B. dendrobatidis infection (number infected per total sampled) were consistently high in frogs (mean 82.5%, minimum 69%) of both species and in tadpoles (100%) during both winter (starting July) and summer (starting February). However, no individuals of either species showed clinical signs of disease, and they remained abundant (3.25 - 8.75 individuals of L. lorica and 6.5-12.5 individuals of L. nannotis found/person/100 m over 13 months). The high-elevation dry sclerophyll site had little canopy cover, low annual precipitation, and a more defined dry season than a nearby rainforest site, where L. nannotis was more negatively affected by chytridiomycosis. We hypothesize this lack of canopy cover allowed the rocks on which frogs perched to warm up, thereby slowing growth and reproduction of the pathogen on the hosts. In addition, we suggest surveys for apparently extinct or rare species should not be limited to core environments.  相似文献   
105.
The new objectives for agri-environment policy recommended by the Policy Commission for the Future of Food and Farming are reviewed and proposals to achieve them are assessed. The Commission proposes a unified scheme, with a 'broad and shallow' tier that would incorporate a whole-farm environmental plan and audit. Participation at this level would be a prerequisite for entry into higher tiers focused on securing regional and national ecological, landscape and bio-diversity priorities. However, the Commission recognizes that further resource protection measures need to be developed to substantiate its design, particularly to enable the delivery of 'wider bio-diversity and landscape benefits'. Innovations in addition to those recommended by the Policy Commission are advocated here. These include adding Cultural options and a two-option Enhanced Level tier. The specifications of the first Enhanced Level option would be based on each farm's Sustainability Index Score. The second option would overcome the 'economics of configuration' problem by encouraging farmers to co-operate to deliver environmental outputs as members of 'environmental clubs'. The possibility of using web-based technology to increase the transparency of agri-environmental payments is also discussed. The design proposed here streamlines, simplifies and increases the efficiency of the existing agri-environment schemes.  相似文献   
106.
107.
OBJECTIVES: The present study aimed to investigate the illicit drug use patterns of long-distance truck drivers. This population is considered to be a special interest group in terms of drug-driving research and policy due to high rates of use, involvement of drugs in truck accidents, and the link between drug use and work-related fatigue. METHODS: Qualitative interview data were collected from 35 long-haul truck drivers in Southeast Queensland and analyzed through grounded theory techniques. Interviews were conducted at truck stops and loading facilities in both metropolitan and regional cites throughout Queensland. RESULTS: High rates of licit and illicit drug use (particularly amphetamines) were reported by the majority of the sample. However, unlike previous studies that focus on fatigue, this research found overlapping and changing motivations for drug use during individual lifetimes. Becker's model of a drug use "career" was utilized to reveal that some drivers begin illicit drug use before they commence truck driving. As well as fatigue, powerful motives such as peer pressure, wanting to fit the trucking "image," socialization, relaxation, and addiction were also reported as contributing factors to self-reported drug driving. CONCLUSIONS: The results indicate that these additional social factors may need to be considered and incorporated with fatigue factors when developing effective drug prevention or cessation policies for truck drivers.  相似文献   
108.
109.
Short-beaked common dolphins (Delphinus delphis) and Atlantic spotted dolphins (Stenella frontalis) are the two most abundant cetacean species in the oceanic waters of Madeira and the Azores. They are of similar size, occur in similar habitats and are regularly observed in mixed-species groups to forage together. Genetic analyses suggested that, within each species, dolphins ranging around both archipelagos belong to the same panmictic population. We tested the hypotheses that (1) within each species, individuals from the two archipelagos belong to a single ecological stock; (2) between species, common and spotted dolphins have distinct trophic niches; using fatty acid (FA) and stable isotope (SI) analyses. Fatty acids and stable isotopes were analysed from 86 blubber and 150 skin samples of free-ranging dolphins, respectively. Sex-related differences were not significant, except for common dolphin FA profiles. In S. frontalis, FA and SI differences between archipelagos suggested that individuals belonged to different ecological stocks, despite the existence of gene flow between the two archipelagos. In D. delphis, differences were more pronounced, but it was not possible to distinguish between stock structure and a seasonal effect, due to differential sampling periods in the Azores and Madeira. Inter-specific comparisons were restricted to the Azores where all samples were collected during summer. Differences in FA proportions, noticeably for FA of dietary origin, as well as in nitrogen SI profiles, confirmed that both species feed on distinct resources. This study emphasizes the need for an integrated approach including both genetic and biochemical analyses for stock assessment, especially in wide-ranging marine top predators.  相似文献   
110.
The activity and movement of the Redlip Parrotfish, Scarus rubroviolaceus, near Wawaloli reef, Hawaii (19°43′06″N, 156°03′11″W), was investigated with active and passive tracking techniques from April through November 2007. Site fidelity was determined and home range sizes were measured for 21 individuals. All individuals showed strong diurnal activity patterns and relatively stable home ranges. Terminal phase individuals had larger home range areas than initial phase fish, and home range size increased with depth. Occasional long forays from the home range were observed in many individuals. Forays often occurred in crepuscular hours and may represent migrations to/from nocturnal sheltering sites. Findings from this study underscore the importance of depth and nighttime shelter migrations as design considerations for effective marine protected areas (MPA) for large parrotfishes.  相似文献   
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