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21.
Research on urban insect pollinators is changing views on the biological value and ecological importance of cities. The abundance and diversity of native bee species in urban landscapes that are absent in nearby rural lands evidence the biological value and ecological importance of cities and have implications for biodiversity conservation. Lagging behind this revised image of the city are urban conservation programs that historically have invested in education and outreach rather than programs designed to achieve high‐priority species conservation results. We synthesized research on urban bee species diversity and abundance to determine how urban conservation could be repositioned to better align with new views on the ecological importance of urban landscapes. Due to insect pollinators’ relatively small functional requirements—habitat range, life cycle, and nesting behavior—relative to larger mammals, we argue that pollinators put high‐priority and high‐impact urban conservation within reach. In a rapidly urbanizing world, transforming how environmental managers view the city can improve citizen engagement and contribute to the development of more sustainable urbanization.  相似文献   
22.
Conservation policy sits at the nexus of natural science and politics. On the one hand, conservation scientists strive to maintain scientific credibility by emphasizing that their research findings are the result of disinterested observations of reality. On the other hand, conservation scientists are committed to conservation even if they do not advocate a particular policy. The professional conservation literature offers guidance on negotiating the relationship between scientific objectivity and political advocacy without damaging conservation science's credibility. The value of this guidance, however, may be restricted by limited recognition of credibility's multidimensionality and emergent nature: it emerges through perceptions of expertise, goodwill, and trustworthiness. We used content analysis of the literature to determine how credibility is framed in conservation science as it relates to apparent contradictions between science and advocacy. Credibility typically was framed as a static entity lacking dimensionality. Authors identified expertise or trustworthiness as important, but rarely mentioned goodwill. They usually did not identify expertise, goodwill, or trustworthiness as dimensions of credibility or recognize interactions among these 3 dimensions of credibility. This oversimplification may limit the ability of conservation scientists to contribute to biodiversity conservation. Accounting for the emergent quality and multidimensionality of credibility should enable conservation scientists to advance biodiversity conservation more effectively.  相似文献   
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Matt McDonald 《环境政策》2016,25(6):1058-1078
Environmental nongovernmental organizations (NGOs) in Australia have struggled to generate and sustain public concern about climate change. If debates about climate policy can be viewed as sites of contestation between competing actors, Australia’s environmental NGOs have found it difficult to compete against countervailing forces that have sought to shape public attitudes to climate action and the contours of policy responses. While to a significant degree this reflects the power of those forces and the sentiments of the government of the day, there is also a case to be made that some of Australia’s most prominent environmental NGOs have appeared wedded to strategies inconsistent with building or sustaining public support for action or guiding policy responses. How have Australia’s largest environmental NGOs engaged climate politics, and why has this engagement taken that form? Pierre Bourdieu’s political sociology provides unique insight for coming to terms with the multifaceted nature of the constraints, opportunities, and drivers of political action, from the context of climate politics to the forces behind Australian NGOs’ engagement with that politics, and the limits of that engagement. Bourdieu’s work also suggests possible avenues for more effective forms of political communication on climate change in the Australian context.  相似文献   
25.
Abstract: As zebra mussels (Dreissena polymorpha) continue to spread among inland lakes of the United States and Canada, there is growing interest from professionals, citizens, and other stakeholders to know which lakes are likely to be colonized by zebra mussels. Thus, we developed a classification of lake suitability for zebra mussels on the basis of measured or estimated concentrations of dissolved calcium in lake water and applied the classification to >11,500 lakes in Wisconsin and the Upper Peninsula of Michigan. The majority of lakes (58%) were classified as unsuitable (<10 mg/L Ca) for survival and reproduction of zebra mussels, 27% were identified as suitable (≥21 mg/L Ca), and 15% were classified as borderline suitable (≥10 and <21 mg/L Ca). Of the 77 inland lakes with confirmed zebra mussel records for which data on dissolved calcium were available, our method classified 74 as suitable and 3 as borderline suitable. To communicate this lake‐specific suitability information and to help prioritize regional efforts to monitor and prevent the expansion of zebra mussels and other invasive species, we developed a web‐based interface (available from http://www.aissmartprevention.wisc.edu/ ). Although we are still uncertain of how access to suitability information ultimately affects decision making, we believe this is a useful case study of building communication channels among researchers, practitioners, and the public.  相似文献   
26.
The COVID-19 pandemic has exposed an interconnected and tightly coupled globalized world in rapid change. This article sets the scientific stage for understanding and responding to such change for global sustainability and resilient societies. We provide a systemic overview of the current situation where people and nature are dynamically intertwined and embedded in the biosphere, placing shocks and extreme events as part of this dynamic; humanity has become the major force in shaping the future of the Earth system as a whole; and the scale and pace of the human dimension have caused climate change, rapid loss of biodiversity, growing inequalities, and loss of resilience to deal with uncertainty and surprise. Taken together, human actions are challenging the biosphere foundation for a prosperous development of civilizations. The Anthropocene reality—of rising system-wide turbulence—calls for transformative change towards sustainable futures. Emerging technologies, social innovations, broader shifts in cultural repertoires, as well as a diverse portfolio of active stewardship of human actions in support of a resilient biosphere are highlighted as essential parts of such transformations.  相似文献   
27.
目的掌握太阳风暴对短波电子装备性能的影响及应对措施,为系统设计提供参考。方法分析太阳风暴的表现形式,并从作用距离、目标检测、定位精度等方面给出太阳风暴对短波超视距雷达、短波通信等装备的影响。结果电离层SID、电离层暴可造成短波通信中断,短波通信可用频段变窄。电离层强吸收可降低天波超视距雷达作用距离和目标定位精度,电子浓度、电离层虚高快速变化影响超视距雷达检测性能和定位精度,负相电离层暴使天波超视距雷达可用频段严重变窄。地球磁暴期间,电磁场突变产生的强电压和电流有可能烧毁用于天、地波超视距雷达的电子设备。电离层非规则现象对超视距雷达有严重影响。结论太阳风暴对电子装备性能有利有弊,要分别对待。系统设计时应充分考虑太阳风暴的影响,在出现太阳风暴时,采取针对性措施降低其影响。  相似文献   
28.
从多年工作经验出发,综述了某测量船舰载短波天线使用过程中出现的主要问题及潜在严重后果,从材料、结构等方面对其进行了深入分析,指出环境考虑不足、材料选择不当、结构存在缺陷是引发以上问题的根本原因。同时,结合工程实践,就如何在现有条件下提高舰载短波天线的可靠性,分别从如何选用合适材料、改进结构设计给出了意见建议。  相似文献   
29.
Vegetation net primary productivity (NPP) is a sensitive indicator to characterize the response of terrestrial ecosystems to the climate change. Projections of the NPP changes of the Loess Plateau under future climate scenarios have great significances in revealing the interactions among terrestrial ecosystems and climatic systems, as well as instructing future vegetation construction of this region. Here, we carried out a case study on the Yangou watershed in the Loess Plateau. Using the vegetation-producing process model (VPP) established for such small watersheds, we simulated the NPP of the Yangou watershed under different scenarios of climate changes. The results showed that the NPP significantly increased with the precipitation increasing and evidently decreased with the temperature increasing where the climate change occurred in the whole year or in the summer half year. However, where the climate change occurred in the winter half year, the increased precipitation had little effect on the NPP, and the increased temperature significantly reduced the NPP. There were clear differences among the response sensitivities of different vegetation types with trees and shrubs were more sensitive to the changes in temperature and precipitation than crops and grasses. Currently, the most favourable climate change scenario to the NPP in the Yangou watershed was T0P15 under which the precipitation increased by 15% and the temperature did not changed, in the whole year; in the meantime, the most unfavourable climate change scenarios was T2P-15 under which the precipitation declined by 15% and the temperature increased by 2℃, in the whole year.  相似文献   
30.
根据国家现有监测技术规范,结合移动通信基站建设和监测工作实践的实际,阐述监测工作的要点及监测设备要求。  相似文献   
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