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81.
Flood management policies in the United States rely on scientific information about the frequency and intensity of extreme precipitation and runoff. Yet, the available information is inherently uncertain because of the complexity of meteorological and hydrological processes. In mountainous areas, flood risk can vary greatly even within short distances depending on local climate, topography, soil characteristics, and land use. This paper describes two Colorado cases in which policy makers were presented with conflicting scientific estimates: revision of the Fort Collins floodplain map and modification of the Cherry Creek Dam. The case studies demonstrate that uncertainty can have substantial impacts on regulatory processes, public safety, and costs. The analysis considers the differing perspectives of various participants in the flood management processes, illustrating the interplay between uncertainties attributable to scientific issues and values issues. It suggests that attempts to provide a single “best” estimate do not necessarily meet the decision needs of all stakeholders. Conclusions indicate a need to improve communication about uncertainty when scientific estimates areprovided to decision makers. Furthermore, in highly controversial decisions, it may be necessary to reframe the discussion to consider the values issues raised by scientific uncertainty.  相似文献   
82.
This article reports for the first time that fullerene (nC60) can form chlorinated disinfection by-products in aqueous systems at ambient temperature. The ability of nC60 to form colloidal suspensions in aqueous media increases the chance that these particles will migrate in the environment and then in drinking water supply systems. Since nC60 is not completely removed by conventional water treatment, any residual nC60 is likely to be oxidized during disinfection process. While the ozonation of nC60 has been studied, little is known about the reaction between nC60 and chlorine. To address this issue, we subjected aqueous nC60 suspensions to chlorination and sequential ozonation/chlorination at ozone dosages of 4.5, 10, 15 and 24 mg O3/mg nC60. The morphology and physicochemical properties of oxidized nC60 aggregates were evaluated by scanning electron microscopy, transmission electron microscopy, UV–visible absorption spectroscopy and X-ray photoelectron spectroscopy (XPS). We found that while the particles in the as-prepared nC60 were predominantly spheres, the ozonation of nC60 resulted in the formation of irregularly shaped aggregates. The concentration of atomic carbon found by XPS in the nC60 samples decreased from 92 % for the as-prepared nC60 to 50 % for the aggregates ozonated at 24 mg O3/mg nC60 and then chlorinated at 68 mg Cl2/L and allowed to react for 100 min. The presence of Cl atoms covalently bonded to C atoms was confirmed by XPS peaks corresponding to a binding energy (E b) of 200.1–202.4 eV. This demonstrates the need to better assess and monitor the formation of potentially toxic chlorinated disinfection by-products from carbon nanomaterials during water treatment.  相似文献   
83.
Musculoskeletal disorders lead to pain and suffering and result in high costs to industry. There is evidence to suggest that whereas conventional ergonomics training programs result in knowledge gains, they may not necessarily translate to changes in behavior. There were 11 participants in an ergonomics training program, and a subsample of participants received a motivational intervention in the form of incentives for correct workstation setup. Training did not yield any changes in ergonomics measures for any participant. Incentives resulted in marked and durable changes in targeted workstation measures. The data suggest that improving worker knowledge about ergonomically correct workstation setup does not necessarily lead to correct workstation setup, and that motivational interventions may be needed to achieve lasting behavior change.  相似文献   
84.
In socially monogamous species, extra-pair paternity may increase the reproductive success of highly ornamented males, mediating the evolution of sexual ornaments. However, ornaments may also attract social mates, and a tradeoff between extra-pair paternity (EPP) and within-pair paternity (WPP) may complicate mating strategies. Further, in many socially monogamous species, females are also ornamented, and the relationship between female ornamentation and patterns of EPP has been neglected. We investigated the patterns of genetic paternity with respect to carotenoid- and melanin-based pigmentation in yellow warblers (Setophaga petechia) of both sexes. We asked whether males face tradeoffs between EPP and WPP, how paternity patterns relate to carotenoid- versus melanin-based pigmentation, and whether less EPP occurs in broods when males and females are assortatively paired. Males faced a tradeoff between EPP and WPP. Moreover, non-additive relationships existed between paternity patterns and the two pigment types in both sexes. Males with high melanin coverage but dull carotenoid pigmentation achieved EPP but lost WPP, whereas males with high levels of both pigment types had high WPP but gained little EPP. A parallel pattern occurred in females. Warblers paired assortatively by pigmentation and EPP was less common in broods when the sexes were assortatively paired by carotenoid pigmentation. Results suggest that the most colorful birds obtain high quality social mates and advance reproductive success through WPP, show that correlations can arise between female ornamentation and patterns of EPP, and also uniquely suggest that social pairing patterns may influence extra-pair mating strategies.  相似文献   
85.
Solutions for conserving biodiversity lie in changing people's behavior. Ambitious international and national conservation policies frequently fail to effectively mitigate biodiversity loss because they rarely apply behavior-change theories. We conducted a gap analysis of conservation behavior-change interventions advocated in national conservation strategies with the Behavior Change Wheel (BCW), a comprehensive framework for systematically characterizing and designing behavior-change interventions. Using pollinator conservation as a case study, we classified the conservation actions listed in national pollinator initiatives in relation to intervention functions and policy categories of the BCW. We included all national-level policy documents from the European Union available in March 2019 that focused on conservation of pollinators (n = 8). A total of 610 pollinator conservation actions were coded using in-depth directed content analysis, resulting in the identification of 787 intervention function and 766 policy category codes. Overall, these initiatives did not employ the entire breadth of behavioral interventions. Intervention functions most frequently identified were education (23%) and environmental restructuring (19%). Least frequently identified intervention functions were incentivization (3%), and restriction (2%) and coercion were completely absent (0%). Importantly, 41% of all pollinator conservation actions failed to identify whose behavior was to be changed. Building on these analyses, we suggest that reasons for the serious implementation gap in national and international conservation policies is founded in insufficient understanding of which behavioral interventions to employ for most beneficial impacts on biodiversity and how to clearly specify the intervention targets. We recommend that policy advisors engage with behavior-change theory to design effective behavior-change interventions that underpin successful conservation policies.  相似文献   
86.
The differential allocation hypothesis proposes that females mated to attractive males should invest more resources in their offspring than those mated to less-attractive males, whereas the compensation hypothesis posits that females mated to less-attractive males should invest more resources in their offspring to compensate for lower-quality young. We tested these hypotheses by manipulating attractiveness of male house wrens (Troglodytes aedon) prior to female arrival by adding extra nest sites to territories of some males while leaving control males with only a single nest site. Females laid their eggs sooner in the nests of attractive males, and attractive males were more likely to retain their territory over successive broods and were marginally more likely to obtain a mate for a second brood later in the season than were control males, thereby confirming the effect of our manipulation on male attractiveness. Experimentally enhanced attractiveness also led to increased hematocrit in males. However, there were no consistent differences in the number, size, or quality of eggs laid by females mated to attractive and control males, nor were there any differences in the size, health state, or immune function of nestlings produced from these eggs. There was also no effect of treatment on the number of nestlings surviving to fledging. Collectively, these results are inconsistent with both the differential allocation hypothesis and the compensation hypothesis. Future studies should consider the possibility that the criteria used by females in selecting a mate may vary temporally and be more flexible than generally thought.  相似文献   
87.
An ongoing debate in ecology is the relationship between community or ecosystem structure and function. This relationship is particularly important in restored ecosystems because it is often assumed that restoring ecosystem structure will restore ecosystem functioning, but this assumption is frequently not tested. In this study, we used a novel application of structural equation modelling (SEM) to examine the relationship between ecosystem structure and function. To exemplify how to apply SEM to explore this relationship, we used a case study examining soil controls on denitrification potential (DNP) in two restored wetlands. Our objectives were to examine (1) whether both restored wetland soil ecosystems had similar relationships among soils variables (i.e. similar soil ecosystem structure) and (2) whether the soil variables driving denitrification potential (DNP) were similar at both sites (i.e. the soil ecosystems were functioning in a similar manner). Using the unique ability of SEM to test model structure, we proposed a SEM to represent the soil ecosystem and tested this structure with field data. We determined that the same model structure was supported by data from both systems suggesting that the two restored wetland systems had similar soil ecosystem structure. To test whether both ecosystems were functioning in a similar way, we examined the parameters of each model. We determined that the drivers of DNP function were not the same at both sites. Higher soil organic matter was the most important predictor of higher DNP at both sites. However, the other significant relationships among soils variables were different at each system indicating that the soils were not functioning in exactly the same way at each site. Overall, these results suggest that the restoration of ecosystem structure may not necessarily ensure the restoration of ecosystem functioning. In this study we capitalize on an inherent feature of SEM, the ability to test model structure, to test a fundamental ecological question. This novel approach is widely applicable to other systems and improves our understanding of the general relationship between ecosystem structure and function.  相似文献   
88.
The development of Watershed Management Plans (WMPs) in urban areas aids municipalities in allocating resources, engaging the public and stakeholders, addressing water quality regulations, and mitigating issues related to stormwater runoff and flooding. In this study, 124 urban WMPs across the United States were reviewed to characterize historic approaches and identify emerging trends in watershed planning. Planning methods and tools were qualitatively evaluated, followed by statistical analyses of a subset of 63 WMPs to identify relationships between planning factors. Plans developed by a municipality or consultant were associated with more occurrences of hydrologic modeling and site‐specific recommendations, and fewer occurrences of characterizing social watershed factors, than plans authored by agencies, organizations, or universities. WMPs in the past decade exhibited greater frequency in the use of pollutant load models and spatially explicit hydrologic and hydraulic models. Project prioritization was found to increasingly focus on feasibility to implement proposed strategies. More recent plans additionally exhibited greater consideration for water quality, ecological health, and public participation. Innovation in planning methods and consideration of future watershed conditions are primary areas that were found to be deficient in the study WMPs, although analysis methods and tools continue to improve in the wake of advancing technology and data availability.  相似文献   
89.
Considerable attention is now being given to the role and importance of education and learning implications of participatory resource and environmental governance. The contention is that such learning has the potential to transform behaviour, and in the case of resource management, may help change current patterns in resource use towards a more sustainable social-ecological system. Our purpose is to establish the opportunities for learning afforded to those participating in local level resource management committees in two Cambodian fishing communities and consider the learning outcomes from such opportunities. Our approach was qualitative and used a case study design. The findings establish a wide range of committee resource management activities that resulted in both instrumental (e.g., learning about administrative procedures) and communicative (e.g., insights into the need to conserve mangroves) learning. It was revealed that such learning can lead to changes in behaviour at the community level (e.g., managing local waste). Our findings also indicated a number of motivators and enablers of learning such as opportunities for dialogue, leadership and the presence of declining resources.  相似文献   
90.
In the United States, the common interest often is conceived as a by-product of the pluralist, interest-group-driven democratic process. Special interests dominate in many political arenas. Consequently, we have lost the language, vocabulary, and ability to talk about the common interest. The way to reverse this trend is to develop and practice with new tools that allow us to articulate what we mean by the common interest in specific contexts. In this article, we leveraged the literature on procedural, substantive, and pragmatic decision making to illustrate how they work together to demonstrate whether and how the common interest was served in three case studies of Healthy Forests Restoration Act implementation on the Apache-Sitgreaves National Forest in Arizona. In two of the cases we found that the common interest was mostly served, while in the third case it was not. Our results raise questions about the ability of procedural criteria or substantive criteria alone to determine effectiveness in decision making. When evaluated together they provide a more complete understanding of how the common interest is or is not served.
Toddi A. SteelmanEmail:
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