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191.
Shults RA Jones BH Kresnow MJ Langlois JA Guerrero JL 《Journal of Safety Research》2004,35(4):447-452
INTRODUCTION: Little population-based information exists about the long-term effects of motor-vehicle crash-related injuries. METHOD: We analyzed data from the 1995 National Health Interview Survey Disability (NHIS-D) Supplement to estimate the prevalence of crash-related disability among noninstitutionalized U.S. adults aged 18 years and older. RESULTS: More than 1.2 million adults were living in their homes with the disabling effects of motor-vehicle crash-related injuries in 1995. The prevalence of crash-related disability was highest for persons in their mid-life years, ages 35-64. Half of the respondents had sustained the injuries more than 5 years before the interview. Forty-one percent of working-aged individuals reported being unable to work because of their disability. CONCLUSIONS: Because crash-related disability is most prevalent during the mid-life years, quality of life and productivity may be affected for decades. These findings highlight the personal and societal burden associated with motor-vehicle crash-related disability in the United States. 相似文献
192.
关于中国的水安全问题及其对策探讨 总被引:20,自引:4,他引:16
随着全球性资源生态危机的加剧及全球化进程的飞速发展 ,国家安全要素扩大到包括资源环境在内的一些非传统安全要素上 ,现今 ,水安全已成为国家安全问题的核心内容之一。为此 ,笔者探讨了我国水安全存在的一些主要问题 ;分析了产生这些问题的原因 ;提供了解决这些问题的对策。 相似文献
193.
李爱霞 《湖南环境生物职业技术学院学报》2008,14(1):49-51
国家助学贷款是我国实施“教育成本分担”、促进“教育机会均等”的一项重大措施.它对支持教育体制改革、促进教育事业发展、提高全民族素质具有十分重要的意义.笔者在深入调查和充分论证的基础上,简要回顾了目前国家助学贷款发展状况,并进一步提出完善的政策措施与建议,以期探寻国家助学货款健康发展的良方.参8. 相似文献
194.
MARC KÉRY STEPHEN J. MORREALE PATRICK J. SULLIVAN BETH GARDNER EVAN G. COOCH JAMES P. LASSOIE 《Conservation biology》2014,28(4):1034-1044
Forest degradation is arguably the greatest threat to biodiversity, ecosystem services, and rural livelihoods. Therefore, increasing understanding of how organisms respond to degradation is essential for management and conservation planning. We were motivated by the need for rapid and practical analytical tools to assess the influence of management and degradation on biodiversity and system state in areas subject to rapid environmental change. We compared bird community composition and size in managed (ejido, i.e., communally owned lands) and unmanaged (national park) forests in the Sierra Tarahumara region, Mexico, using multispecies occupancy models and data from a 2‐year breeding bird survey. Unmanaged sites had on average higher species occupancy and richness than managed sites. Most species were present in low numbers as indicated by lower values of detection and occupancy associated with logging‐induced degradation. Less than 10% of species had occupancy probabilities >0.5, and degradation had no positive effects on occupancy. The estimated metacommunity size of 125 exceeded previous estimates for the region, and sites with mature trees and uneven‐aged forest stand characteristics contained the highest species richness. Higher estimation uncertainty and decreases in richness and occupancy for all species, including habitat generalists, were associated with degraded young, even‐aged stands. Our findings show that multispecies occupancy methods provide tractable measures of biodiversity and system state and valuable decision support for landholders and managers. These techniques can be used to rapidly address gaps in biodiversity information, threats to biodiversity, and vulnerabilities of species of interest on a landscape level, even in degraded or fast‐changing environments. Moreover, such tools may be particularly relevant in the assessment of species richness and distribution in a wide array of habitats. Uso de Modelos de Ocupación para Múltiples Especies para Evaluar la Respuesta de las Comunidades de Aves a la Degradación de Bosques Asociada con la Tala 相似文献
195.
The necessity of compensating people negatively affected by conservation and other development projects has been widely acknowledged. It is less widely acknowledged that because conventional compensation assessments focus on material resources and their economic equivalents, many important losses incurred by resettlers are invisible to project authorities. Through ethnographic observations and interviews, we documented losses identified by people facing resettlement from Mozambique's Limpopo National Park. We also examined resettlement planning documents to determine why decision makers’ assessments of natural resource use and value neglect losses residents identified as critical. Identifying, preventing, and mitigating invisible losses in resettlement planning necessitates a better understanding of intangible benefits residents derive from resources, which are often as or more important than their readily apparent material properties. These benefits include but are not limited to decision‐making authority linked to owning land versus having the use of fields; ancestral identity and social belonging linked to gravesites; the importance of tree roots that provide a powerful sense of security because they suppress hunger in periods of scarcity; and the importance of people's location within social networks and hierarchies as they determine the benefits versus risks that will be incurred through resettlement. Pérdidas Invisibles y la Lógica de la Compensación de Repoblación 相似文献
196.
基于大数据的视角对1993—2013年我国国家社科基金旅游项目进行了全样本统计和研究,并采用SPSS17.0软件对项目负责人、负责人所在单位、单位所在省市进行了描述性分析和聚类分析,同时借助ROSTCM6软件对项目主题进行了语义网络分析,全面展示了国家社科基金旅游项目反映的我国旅游发展格局,系统认识和评价国家社科基金旅游项目对我国旅游研究的贡献有一定的指导作用。 相似文献
197.
Daniel Ovando Jennifer E. Caselle Christopher Costello Olivier Deschenes Steven D. Gaines Ray Hilborn Owen Liu 《Conservation biology》2021,35(6):1861-1870
Marine protected areas (MPAs) cover 3–7% of the world's ocean, and international organizations call for 30% coverage by 2030. Although numerous studies show that MPAs produce conservation benefits inside their borders, many MPAs are also justified on the grounds that they confer conservation benefits to the connected populations that span beyond their borders. A network of MPAs covering roughly 20% of the Channel Islands National Marine Sanctuary was established in 2003, with a goal of providing regional conservation and fishery benefits. We used a spatially explicit bioeconomic simulation model and a Bayesian difference-in-difference regression to examine the conditions under which MPAs can provide population-level conservation benefits inside and outside their borders and to assess evidence of those benefits in the Channel Islands. As of 2017, we estimated that biomass densities of targeted fin-fish had a median value 81% higher (90% credible interval: 23–148) inside the Channel Island MPAs than outside. However, we found no clear effect of these MPAs on mean total biomass densities at the population level: estimated median effect was –7% (90% credible interval: –31 to 23) from 2015 to 2017. Our simulation model showed that effect sizes of MPAs of <30% were likely to be difficult to detect (even when they were present); smaller effect sizes (which are likely to be common) were even harder to detect. Clearly, communicating expectations and uncertainties around MPAs is critical to ensuring that MPAs are effective. We provide a novel assessment of the population-level effects of a large MPA network across many different species of targeted fin-fish, and our results offer guidance for communities charged with monitoring and adapting MPAs. 相似文献
198.
199.
Christopher A. Monz Kevin J. Gutzwiller Vera Helene Hausner Mark W. Brunson Ralf Buckley Catherine M. Pickering 《Ambio》2021,50(3):631
Disturbance to ecosystems in parks and protected areas from nature-based tourism and recreation is increasing in scale and severity, as are the impacts of climate change—but there is limited research examining the degree to which these anthropogenic disturbances interact. In this perspective paper, we draw on the available literature to expose complex recreation and climate interactions that may alter ecosystems of high conservation value such that important species and processes no longer persist. Our emphasis is on ecosystems in high demand for tourism and recreation that also are increasingly experiencing stress from climate change. We discuss the importance of developing predictive models of direct and indirect effects, including threshold and legacy effects at different levels of biological organization. We present a conceptual model of these interactions to initiate a dialog among researchers and managers so that new research approaches and managerial frameworks are advanced to address this emerging issue. 相似文献
200.
Benjamin J. Crain Chad Stachowiak Patrick F. McKenzie James N. Sanchirico Kailin Kroetz Paul R. Armsworth 《Ambio》2021,50(6):1237
Open space areas protected by local communities may augment larger scale preservation efforts and may offer overlooked benefits to biodiversity conservation provided they are in suitable ecological condition. We examine protected areas established by local communities through ballot initiatives, a form of direct democracy, in California, USA. We compare ecological conditions of wooded habitats on local ballot protected sites and on sites protected by a state-level conservation agency. Collectively, we found few differences in ecological conditions on each protected area type. Ballot sites had greater invasive understory cover and larger trees. Community dissimilarity patterns suggested ballot sites protect a complementary set of tree species to those on state lands. Overall, geographic characteristics influenced onsite conditions more than details of how sites were protected. Thus, community-driven conservation efforts contribute to protected area networks by augmenting protection of some species while providing at least some protection to others that might otherwise be missed.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01469-8) contains supplementary material, which is available to authorized users. 相似文献