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71.
Bias toward legally protecting and prioritizing charismatic taxonomic groups, such as mammals and birds, and against others, such as insects and plants, is well documented. However, the relative costs of conserving various taxonomic groups and the potential of these costs to interact with existing biases have been much less explored. We analyzed conservation programs across more than 2,000 species in 3 countries to investigate the costs of conserving species within taxonomic groups and how these costs might affect conservation planning. For each data set, we tested for differences in mean annual cost among taxonomic groups. For the data set from the United States, recovery plans differed in duration, so we also tested for differences in total costs among taxonomic groups. Although the costs for individual species varied widely, there were strong international consistencies. For example, mammals cost 8–26 times more on average to conserve than plants and 13–19 times more to conserve than aquatic invertebrates. On average, bird species cost 5–30 times more to conserve than plants and 6–14 times more to conserve than aquatic invertebrates. These cost differences could exacerbate unequal resource allocation among taxonomic groups such that more charismatic groups both receive more attention and require more resources, leading to neglect of other taxonomic groups.  相似文献   
72.
In this article, we describe a parallel agent-based model of spatial opinion diffusion that is driven by graphics processing units (GPUs). Modeling opinion exchange and diffusion across landscapes often involves the simulation of large numbers of geographically located individual decision-makers and a massive number of individual-level interactions. This simulation requires substantial computational power. GPU-enabled computing resources provide a massively parallel processing platform based on a fine-grained shared memory paradigm. This massively parallel processing platform holds considerable promise for meeting the computing requirement of agent-based models of spatial problems. In this article, we focus on the parallelization of an agent-based spatial opinion model using GPU technologies. We discussed key algorithms designed for parallel agent-based opinion modeling: including domain decomposition and mutual exclusion. Experiments conducted to examine computing performance show that GPUs provide a computationally efficient alternative to traditional parallel computing architectures and substantially accelerate agent-based models of large-scale opinion exchange among individual decision makers.  相似文献   
73.
Tobin, Kenneth J. and Marvin E. Bennett, 2012. Validation of Satellite Precipitation Adjustment Methodology From Seven Basins in the Continental United States. Journal of the American Water Resources Association (JAWRA) 48(2): 221‐234. DOI: 10.1111/j.1752‐1688.2011.00604.x Abstract: The precipitation science community has expressed concern regarding the ability of satellite‐based precipitation products to accurately capture rainfall values over land. There has been some work that has focused on addressing the deficiencies of satellite precipitation products, particularly on the adjustment of bias. This article outlines a methodology that adjusts satellite products utilizing ground‐based precipitation data. The approach is not a simple bias adjustment, but is a three‐step process that transforms a satellite product based on a ground‐based precipitation product (NEXRAD‐derived Multisensor Precipitation Estimator [MPE] product or rain‐gauge data). The developed methodology was successfully applied to seven moderate‐to‐large sized watersheds from continental United States (CONUS) and northern Mexico over a spectrum of climatic regimes ranging from dry to humid settings. Methodology validation is based on comparison of observed and simulated streamflow generated with SWAT (Soil and Water Assessment Tool) model using unadjusted and adjusted precipitation products as input. Streamflow comparison is based on mass balance error and Nash‐Sutcliffe efficiency coefficient. Finally, the contribution of how adjustment to correct misses, false alarms, and bias impacts adjusted datasets and the potential impact that the adjustment methodology can have on hydrological applications such as water resource monitoring and flood prediction are explored.  相似文献   
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Park planning, once at the root of the profession during the nineteenth century, can again provide cities with a means to improve public health through restricting access to automobiles. This intercept study, conducted in New Orleans City Park, found that two-thirds of users support weekend street closures to automobiles. Widespread support (63%) exists even among the 72% of people who arrived by automobile. This study also found measurable stated benefits from restricting car access. For more than 53% of the sample that stated that they would walk more in a car-free zone, respondents noted that they would walk nearly 30?min more per month. These findings suggest that planners and policy-makers have a cost-effective option to improve cities and public health – taming the automobile in urban parks.  相似文献   
76.
The knowledge-action gap in conservation science and practice occurs when research outputs do not result in actions to protect or restore biodiversity. Among the diverse and complex reasons for this gap, three barriers are fundamental: knowledge is often unavailable to practitioners and challenging to interpret or difficult to use or both. Problems of availability, interpretability, and useability are solvable with open science practices. We considered the benefits and challenges of three open science practices for use by conservation scientists and practitioners. First, open access publishing makes the scientific literature available to all. Second, open materials (detailed methods, data, code, and software) increase the transparency and use of research findings. Third, open education resources allow conservation scientists and practitioners to acquire the skills needed to use research outputs. The long-term adoption of open science practices would help researchers and practitioners achieve conservation goals more quickly and efficiently and reduce inequities in information sharing. However, short-term costs for individual researchers (insufficient institutional incentives to engage in open science and knowledge mobilization) remain a challenge. We caution against a passive approach to sharing that simply involves making information available. We advocate a proactive stance toward transparency, communication, collaboration, and capacity building that involves seeking out and engaging with potential users to maximize the environmental and societal impact of conservation science.  相似文献   
77.
This paper highlights some recent trends and developments in dialogue on radioactive waste management in the UK. In particular, it focuses on the use of dialogue around options for the management of risk, and describes techniques for stakeholder dialogue in the field of radioactive waste management. The paper summarises past and on-going experience in the UK, and provides an overview of some practical examples from decommissioning of the former reprocessing facility at Dounreay in Scotland. In common with developments and trend in other countries, the UK has moved to a position where there is now widespread recognition that radioactive waste management requires not only sound technical assessment of risk, but also public participation, consultation and stakeholder dialogue on proposed solutions and the associated risks. In fact, the shift of position has arguably been quite pronounced, with formal procedures to identify, clarify and integrate stakeholders' issues and concerns within the decision-making processes. Experience suggests that citizens are capable of engaging with complex technical issues such as radioactive waste. Indeed, the earlier in the decision-making process that public and stakeholder engagement (PSE) occurs--for example, on the consideration of options and alternatives--the greater the chance of reaching a successful outcome that properly reflects the values and opinions of stakeholders. In the UK, the assessment of alternative waste management options is increasingly being addressed through Best Practical Environmental Option (BPEO) studies. Responses to stakeholder engagement processes and experience of conducting BPEO studies emphasise that consultation must be open, transparent, deliberative and inclusive. However, while early consideration of generic approaches and option choices is necessary to generate a climate of openness and understanding, it remains essential to fully engage with local stakeholder and community groups to consider issues associated with proposed developments at a site-specific level. An interesting area where further attention may be warranted is the use in final decision-making of the results from participatory processes such as BPEO studies. Demonstrating clearly that participants' views have influenced decisions appears to be essential for retaining legitimacy and trust, confidence and goodwill.  相似文献   
78.
Manure applied to agricultural land at rates that exceed annual crop nutrient requirements can be a source of phosphorus in runoff. Manure incorporation is often recommended to reduce phosphorus losses in runoff. A small plot rainfall simulation study was conducted at three sites in Alberta to evaluate the effects of manure rate and incorporation on phosphorus losses. Treatments consisted of three solid beef cattle manure application rates (50, 100, and 200 kg ha(-1) total phosphorus), an unmanured control, and two incorporation methods (nonincorporated and incorporated with one pass of a double disk). Simulated rain was applied to soils with freshly applied and residual (1 yr after application) manure at 70 mm h(-1) to produce 30 min of runoff. Soil test phosphorus (STP), total phosphorus (TP), and dissolved reactive phosphorus (DRP) concentrations in runoff increased with manure rate for fresh and residual manure. Initial abstraction and runoff volumes did not change with manure rate. Initial abstraction, runoff volumes, and phosphorus concentrations did not change with manure incorporation at Lacombe and Wilson, but initial abstraction volumes increased and runoff volumes and phosphorus concentrations decreased with incorporation of fresh manure at Beaverlodge. Phosphorus losses in runoff were directly related to phosphorus additions. Extraction coefficients (slopes of the regression lines) for the linear relationships between residual manure STP and phosphorus in runoff were 0.007 to 0.015 for runoff TP and 0.006 to 0.013 for runoff DRP. While incorporation of manure with a double disk had no significant effect on phosphorus losses in runoff from manure-amended soils 1 yr after application, incorporation of manure is still recommended to control nitrogen losses, improve crop nutrient uptake, and potentially reduce odor concerns.  相似文献   
79.
The present study examined whether employees high in negative affectivity (NA) are destined to experience strain at a higher level than those low in NA. We used data collected from 230 employees to investigate the moderating effects of political skill, as a form of interpersonal control, on the relationship between NA and physiological strain. As hypothesized, NA was positively related to physiological strain (i.e., facial muscle tension as measured by electromyography (EMG)), and political skill buffered this effect such that the relationship was weaker among employees who were higher in political skill. Tests of mediated moderation further suggested the means by which political skill moderates the NA/strain relationship; specifically, the results were consistent with the idea that perceived control and, in turn, job‐related efficacy explain the moderating effect of political skill. Strengths and limitations of the study, practical implications, and directions for future research are discussed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
80.
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