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281.
Water is essential for human life, yet safe drinking water is a limited resource. Critical to fighting the global water crisis are public awareness campaigns, including Public Service Announcements (PSAs). While YouTube has become a popular medium for disseminating prosocial content such as PSAs, environmental communication efforts on this platform remain largely uninvestigated. This study examines the content and characteristics of global water crisis PSAs on YouTube by applying two communication models: the Extended Parallel Process Model, and the Elaboration Likelihood Model. These models are used to evaluate the potential effectiveness of the PSAs. Content analysis reveals that threat messages often outweigh efficacy messages in the videos, central route processing cues are more prevalent than peripheral route cues, and a focus on quality or quantity issues differed by sponsoring organization (non-profit, for-profit, government). Implications and avenues for potential future research are discussed.  相似文献   
282.
Large carnivores are persecuted globally because they threaten human industries and livelihoods. How this conflict is managed has consequences for the conservation of large carnivores and biodiversity more broadly. Mitigating human–predator conflict should be evidence‐based and accommodate people's values while protecting carnivores. Despite much research into human and large‐carnivore coexistence strategies, there have been few attempts to document the success of conflict‐mitigation strategies on a global scale. We conducted a meta‐analysis of global research on conflict mitigation related to large carnivores and humans. We focused on conflicts that arise from the threat large carnivores pose to livestock. We first used structured and unstructured searching to identify replicated studies that used before–after or control–impact design to measure change in livestock loss as a result of implementing a management intervention. We then extracted relevant data from these studies to calculate an overall effect size for each intervention type. Research effort and focus varied among continents and aligned with the histories and cultures that shaped livestock production and attitudes toward carnivores. Livestock guardian animals most effectively reduced livestock losses. Lethal control was the second most effective control, although its success varied the most, and guardian animals and lethal control did not differ significantly. Financial incentives have promoted tolerance of large carnivores in some settings and reduced retaliatory killings. We suggest coexistence strategies be location‐specific, incorporate cultural values and environmental conditions, and be designed such that return on financial investment can be evaluated. Improved monitoring of mitigation measures is urgently required to promote effective evidence‐based policy.  相似文献   
283.
We reviewed recent work concerning the impact of geopolitics on wildlife conservation (and vice versa) and identified future priorities in conservation geopolitics research. Geopolitics is understood as both an analytical focus on geopolitical practices (especially concerning the behavior) of countries with respect to territory and national security and a set of theories developed to explain and predict those behaviors. We developed a typology of core geopolitical practices of relevance to conservation: territorial practices of colonization and the management of migrations and borders, and security practices relating to military, economic, and environmental security. We identified research that considers how these practices affect conservation situations and outcomes, noting the recent emergence of conceptual developments such as “environmental geopolitics” and “geopolitical ecology” that draw on multiple fields within the social sciences to theorize the links between geopolitics and environmental management. We defined a "geopolitical perspective" as a focus on geopolitical practices combined with an explicit engagement with geopolitical theory and identified conservation situations where this perspective could contribute to analytical clarity. We suggest the most pressing questions in conservation research to which the geopolitical perspective might contribute are how political and economic differences between countries affect biodiversity outcomes, how geopolitical practices to address those differences facilitate or frustrate conservation efforts, how national borders and human and wildlife movements can be better managed for the benefit of both, and how the most effective conservation strategies can be best selected to suit existing (and future) geopolitical realities.  相似文献   
284.
The concept of empowering leadership (EL) has seen increasing scholarly interest in recent years. This study reports a meta‐analysis investigating the effects of EL on employee work behavior. On the basis of data from 105 samples, we found evidence for the positive effects of EL on performance, organizational citizenship behavior, and creativity at both the individual and team levels. We further examined these relationships by exploring potential boundary conditions and the incremental contribution of EL over transformational leadership and leader–member exchange. Furthermore, at the individual level, both trust in leader and psychological empowerment mediated the relationships of EL with task performance, organizational citizenship behavior, and creativity. We also found evidence that leader–member exchange was a significant mediator between EL and task performance. At the team level, empowerment mediated the effects of EL on team performance, whereas knowledge sharing showed no significant indirect effect. Our results have important theoretical and practical implications and suggest some areas that require further research.  相似文献   
285.
286.
A prevailing view in dryland systems is that mammals are constrained by the scarcity of fertile soils and primary productivity. An alternative view is that predation is a primary driver of mammal assemblages, especially in Australia, where 2 introduced mesopredators—feral cat (Felis catus) and red fox (Vulpes vulpes)—are responsible for severe declines of dryland mammals. We evaluated productivity and predation as drivers of native mammal assemblage structure in dryland Australia. We used new data from 90 sites to examine the divers of extant mammal species richness and reconstructed historic mammal assemblages to determine proportional loss of mammal species across broad habitat types (landform and vegetation communities). Predation was supported as a major driver of extant mammal richness, but its effect was strongly mediated by habitat. Areas that were rugged or had dense grass cover supported more mammal species than the more productive and topographically simple areas. Twelve species in the critical weight range (CWR) (35–5500 g) that is most vulnerable to mesopredator predation were extirpated from the continent's central region, and the severity of loss of species correlated negatively with ruggedness and positively with productivity. Based on previous studies, we expect that habitat mediates predation from red foxes and feral cats because it affects these species’ densities and foraging efficiency. Large areas of rugged terrain provided vital refuge for Australian dryland mammals, and we predict such areas will support the persistence of CWR species in the face of ongoing mammal declines elsewhere in Australia.  相似文献   
287.
Conservation actions, such as habitat protection, attempt to halt the loss of threatened species and help their populations recover. The efficiency and the effectiveness of actions have been examined individually. However, conservation actions generally occur simultaneously, so the full suite of implemented conservation actions should be assessed. We used the conservation actions underway for all threatened and near‐threatened birds of the world (International Union for Conservation of Nature Red List of Threatened Species) to assess which biological (related to taxonomy and ecology) and anthropogenic (related to geoeconomics) factors were associated with the implementation of different classes of conservation actions. We also assessed which conservation actions were associated with population increases in the species targeted. Extinction‐risk category was the strongest single predictor of the type of conservation actions implemented, followed by landmass type (continent, oceanic island, etc.) and generation length. Species targeted by invasive nonnative species control or eradication programs, ex situ conservation, international legislation, reintroduction, or education, and awareness‐raising activities were more likely to have increasing populations. These results illustrate the importance of developing a predictive science of conservation actions and the relative benefits of each class of implemented conservation action for threatened and near‐threatened birds worldwide.  相似文献   
288.
Regional Environmental Change - As climate change impacts, particularly rising sea levels, manifest there is a high probability that some island populations will be faced with the need to relocate....  相似文献   
289.
Entanglement in fixed fishing gear affects whales worldwide. In the United States, deaths of North Atlantic right (Eubalaena glacialis) and humpback whales (Megaptera novaeangliae) have exceeded management limits for decades. We examined live and dead whales entangled in fishing gear along the U.S. East Coast and the Canadian Maritimes from 1994 to 2010. We recorded whale species, age, and injury severity and determined rope polymer type, breaking strength, and diameter of the fishing gear. For the 132 retrieved ropes from 70 cases, tested breaking strength range was 0.80–39.63 kN (kiloNewtons) and the mean was 11.64 kN (SD 8.29), which is 26% lower than strength at manufacture (range 2.89–53.38 kN, mean = 15.70 kN [9.89]). Median rope diameter was 9.5 mm. Right and humpback whales were found in ropes with significantly stronger breaking strengths at time of manufacture than minke whales (Balaenoptera acuturostrata) (19.30, 17.13, and 10.47 mean kN, respectively). Adult right whales were found in stronger ropes (mean 34.09 kN) than juvenile right whales (mean 15.33 kN) and than all humpback whale age classes (mean 17.37 kN). For right whales, severity of injuries increased since the mid 1980s, possibly due to changes in rope manufacturing in the mid 1990s that resulted in production of stronger ropes at the same diameter. Our results suggest that broad adoption of ropes with breaking strengths of ≤7.56 kN (≤1700 lbsf) could reduce the number of life‐threatening entanglements for large whales by at least 72%, and yet could provide sufficient strength to withstand the routine forces involved in many fishing operations. A reduction of this magnitude would achieve nearly all the mitigation legally required for U.S. stocks of North Atlantic right and humpback whales. Ropes with reduced breaking strength should be developed and tested to determine the feasibility of their use in a variety of fisheries.  相似文献   
290.
Environmental Science and Pollution Research - Aquatic environments are now recognized secondary habitat of potentially pathogenic Escherichia coli. In this study, PCR-based analyses were used to...  相似文献   
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