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排序方式: 共有356条查询结果,搜索用时 669 毫秒
271.
Iain Dickson Stuart H. M. Butchart Allison Catalano David Gibbons Julia P. G. Jones Katie Lee-Brooks Thomasina Oldfield David Noble Stuart Paterson Sugoto Roy Julien Semelin Paul Tinsley-Marshall Rosie Trevelyan Hannah Wauchope Sylvia Wicander William J. Sutherland 《Conservation biology》2023,37(1):e13967
Although some sectors have made significant progress in learning from failure, there is currently limited consensus on how a similar transition could best be achieved in conservation and what is required to facilitate this. One of the key enabling conditions for other sectors is a widely accepted and standardized classification system for identifying and analyzing root causes of failure. We devised a comprehensive taxonomy of root causes of failure affecting conservation projects. To develop this, we solicited examples of real-life conservation efforts that were deemed to have failed in some way, identified their underlying root causes of failure, and used these to develop a generic, 3-tier taxonomy of the ways in which projects fail, at the top of which are 6 overarching cause categories that are further divided into midlevel cause categories and specific root causes. We tested the taxonomy by asking conservation practitioners to use it to classify the causes of failure for conservation efforts they had been involved in. No significant gaps or redundancies were identified during this testing phase. We then analyzed the frequency that particular root causes were encountered by projects within this test sample, which suggested that some root causes were more likely to be encountered than others and that a small number of root causes were more likely to be encountered by projects implementing particular types of conservation action. Our taxonomy could be used to improve identification, analysis, and subsequent learning from failed conservation efforts, address some of the barriers that currently limit the ability of conservation practitioners to learn from failure, and contribute to establishing an effective culture of learning from failure within conservation. 相似文献
272.
Noa Pinter-Wollman Julia Hubler Jo-Anne Holley Nigel R. Franks Anna Dornhaus 《Behavioral ecology and sociobiology》2012,66(10):1407-1420
How social insect colonies behave results from the actions of their workers. Individual variation among workers in their response to various tasks is necessary for the division of labor within colonies. A worker may be active in only a subset of tasks (specialist), perform all tasks (elite), or exhibit no particular pattern of task activity (idiosyncratic). Here we examine how worker activity is distributed among and within tasks in ants of the genus Temnothorax. We found that workers exhibited elitism within a situation, i.e., in particular sets of tasks, such as those associated with emigrations, nest building, or foraging. However, there was weak specialization for working in a particular situation. A few workers exhibited elitism across all situations, i.e., high performance in all tasks in all situations. Within any particular task, the distribution of activity among workers was skewed, with few ants performing most of the work and most ants performing very little of the work. We further found that workers persisted in their task preference over days, with the same individuals performing most of the work day after day. Interestingly, colonies were robust to the removal of these highly active workers; they were replaced by other individuals that were previously less active. This replacement was not short-lived; when the removed individuals were returned to the colony, not all of them resumed their prior high activity levels, and not all the workers that replaced them reduced their activity. Thus, even though some workers specialize in tasks within a particular situation and are persistent in performing them, task allocation in a colony is plastic and colonies can withstand removal of highly active individuals. 相似文献
273.
Seventeen immature green turtles Chelonia mydas were tracked concurrently by automated ultrasonic receivers at a coral reef off North-Eastern Australia (September–December 2010, 16.4°S, 145.6°E). The majority (n = 11) were tracked for the entire 100-day study, the remainder for 23–85 days. Detection data aggregated at 30-min intervals produced median 6.5–35 daily locations for individual turtles. Home range areas (95 % utilisation distribution) were ≤1 km2, $ {\bar{\text{x}}} $ ± SD = 0.74 km2 ± 0.159. To the best of our knowledge, these are the first home range estimates for C. mydas foraging at offshore tropical reefs. The findings are important for conservation in revealing near-continuous presence of the same individuals within a small geographic area. Time between detections was very short (median <3 min) demonstrating passive ultrasonic technology can track multiple turtles in a foraging environment with higher temporal resolution than typically achieved by satellite tracking. 相似文献
274.
275.
At the centre of the debate surrounding sustainable development is a recognition that companies can make a major contribution by being environmentally and socially responsible and that tools associated with these concepts can enhance the competitiveness and economic performance of the firm. In this paper we go further in arguing that in a world of globalisation it is equally important to look at issues of international trade. In an examination of free trade we argue that it is neither fully consistent with sustainable development nor to the benefit of business. We point to a new imperative to develop sound sourcing, and equitable and fair trading relationships. We identify issues associated with fair trade (including issues of human rights, fair wages, sustainability reporting procedures and codes of conduct on ethics) and associated tools of analysis (guaranteed prices, codes of conduct and end price audits). The paper argues that in a world of globalisation with greater transparency and information availability it will be important for companies to be clear about their policies on supply chain management and trade. Indeed, with the growth of an active and sophisticated civil society, it will be argued that policies associated with sound sourcing, equitable trade and fair trade could provide companies with a new competitive strategy based on ethical standards communicated to the consumer through a strategy of differentiation. We explore strategies for the integration of fair trade policies, strategies and standards, and the opportunities for new markets and niches that this presents. It is argued that the integration of fair trade into a business strategy can enhance competitiveness. 相似文献
276.
This paper examines the problem of measuring sustainable governance in the European Union (EU-27) through the use of duality and the Slutsky equation. The proposed methodology is based on the application of a three-dimensional optimisation model, where the arguments of the objective (sustainable social welfare) function are economic goods that contribute to sustainable economic growth; environmental goods that provide for sustainable environmental protection; and social goods through which sustainable social development is achieved. The dual problem, formulated through this three-dimensional theoretical model, is solved to find the optimal solution, indicating a certain sustainability level. We suggest that this solution can be used for calculating the value of what we define here as the sustainable governmental policy indicator, which is considered to provide quantitative measurement of government policies on sustainable development within the context of ‘good governance’. Furthermore, it is suggested that the Slutsky equation can be used as a reliable method for long-term monitoring and planning of national as well as international good governance with regard to sustainable development policies. In its empirical part, the paper applies the theoretical model in an analysis of the sustainable development indicators (as set out in the Sustainable Development Strategy (SDS) of the EU) in Bulgaria for the period 2000–2010 and compares them to those of the EU-27. 相似文献
277.
Julia Bartmess-LeVasseur Carrie L. Branch Sheri A. Browning Jessica L. Owens Todd M. Freeberg 《Behavioral ecology and sociobiology》2010,64(7):1187-1198
Evidence from different chickadee species (Poecile genus) indicates that birds can modify the note composition of their “chick-a-dee” calls in the presence of predator stimuli.
Here, we tested the effects of predator models and the distance of those models on calls of three species foraging together
at feeding stations: Carolina chickadees (Poecile carolinensis) and tufted titmice (Baeolophus bicolor), both members of the Paridae family, and white-breasted nuthatches (Sitta carolinensis), a member of the Sittidae family. Model and distance affected seed-taking rates in all three species. “Chick-a-dee” calling
rates were higher in the predator context for both chickadees and titmice, but we detected no predator context effects on
“quank” call rates for nuthatches. Predator and distance contexts affected acoustic parameters of notes of the “chick-a-dee”
calls of chickadees and titmice; no such effects were detected for nuthatch “quank” calls. These results suggest species differences
in encoding of information in the primary social calls of these three species that commonly occur in multi-species flocks.
Chickadees and titmice are “nuclear” species and nuthatches are “satellite” species, and these different roles might be related
to the differences in vocal signaling that we detected. 相似文献
278.
Summaries
Summaries 相似文献279.
Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased. 相似文献
280.
Francisco J. Lopez-Valdes Krystoffer Mroz Andre Eggers Bengt Pipkorn Julia Muehlbauer Sylvia Schick 《Traffic injury prevention》2018,19(8):S55-S63
AbstractObjective: The goal of the study was to develop experimental chest loading conditions that would cause up to Abbreviated Injury Scale (AIS) 2 chest injuries in elderly occupants in moderate-speed frontal crashes. The new set of experimental data was also intended to be used in the benchmark of existing thoracic injury criteria in lower-speed collision conditions.Methods: Six male elderly (age >63) postmortem human subjects (PMHS) were exposed to a 35?km/h (nominal) frontal sled impact. The test fixture consisted of a rigid seat, rigid footrest, and cable seat back. Two restraint conditions (A and B) were compared. Occupants were restrained by a force-limited (2.5?kN [A] and 2?kN [B]) seat belt and a preinflated (16?kPa [A] and 11?kPa [B]; airbag). Condition B also incorporated increased seat friction. Matching sled tests were carried out with the THOR-M dummy. Infra-red telescoping rod for the assessment of chest compression (IRTRACC) readings were used to compute chest injury risk. PMHSs were exposed to a posttest injury assessment. Tests were carried out in 2 stages, using the outcome of the first one combined with a parametric study using the THUMS model to adjust the test conditions in the second. All procedures were approved by the relevant ethics board.Results: Restraint condition A resulted in an unexpected high number of rib fractures (fx; 10, 14, 15 fx). Under condition B, the adjustment of the relative airbag/occupant position combined with a lower airbag pressure and lower seat belt load limit resulted in a reduced pelvic excursion (85 vs. 110?mm), increased torso pitch and a substantially lower number of rib fractures (1, 0, 4 fx) as intended.Conclusions: The predicted risk of rib fractures provided by the THOR dummy using the Cmax and PC Score injury criteria were lower than the actual injuries observed in the PMHS tests (especially in restraint condition A). However, the THOR dummy was capable of discriminating between the 2 restraint scenarios. Similar results were obtained in the parametric study with the THUMS model. 相似文献