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11.
Seed plant phylogenetic diversity and species richness in conservation planning within a global biodiversity hotspot in eastern Asia 下载免费PDF全文
One of the main goals of conservation biology is to understand the factors shaping variation in biodiversity across the planet. This understanding is critical for conservation planners to be able to develop effective conservation strategies. Although many studies have focused on species richness and the protection of rare and endemic species, less attention has been paid to the protection of the phylogenetic dimension of biodiversity. We explored how phylogenetic diversity, species richness, and phylogenetic community structure vary in seed plant communities along an elevational gradient in a relatively understudied high mountain region, the Dulong Valley, in southeastern Tibet, China. As expected, phylogenetic diversity was well correlated with species richness among the elevational bands and among communities. At the community level, evergreen broad‐leaved forests had the highest levels of species richness and phylogenetic diversity. Using null model analyses, we found evidence of nonrandom phylogenetic structure across the region. Evergreen broad‐leaved forests were phylogenetically overdispersed, whereas other vegetation types tended to be phylogenetically clustered. We suggest that communities with high species richness or overdispersed phylogenetic structure should be a focus for biodiversity conservation within the Dulong Valley because these areas may help maximize the potential of this flora to respond to future global change. In biodiversity hotspots worldwide, we suggest that the phylogenetic structure of a community may serve as a useful measure of phylogenetic diversity in the context of conservation planning. 相似文献
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绿色发展是我国"十三五"时期五大发展理念之一,是解决我国发展与保护矛盾的根本途径。系统动力学是模拟宏观社会经济发展趋势和政策效力的常用分析工具,本文对系统动力学在中国区域绿色发展政策仿真中的应用进行了梳理。研究显示:系统动力学应用的区域范围方面,该方法全面应用于从国家直至县域等各个尺度的区域绿色发展研究,区域绿色发展通常被分解为经济、社会、资源、环境等子系统;应用的主要领域方面,水土资源、能源、水环境、固废治理、绿色产业等领域应用较多,大气环境、绿色消费等领域应用相对较少;方法的改进和完善方面,软系统分析法、各类优化方法和地理信息系统与系统动力学的集成应用日益普遍。文末根据文献梳理情况,提出未来应在决策变量设计、历史数据挖掘、环境系统对经济系统的反馈等方面进行方法改进。 相似文献
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Small body size is generally correlated with r‐selected life‐history traits, including early maturation, short‐generation times, and rapid growth rates, that result in high population turnover and a reduced risk of extinction. Unlike other classes of vertebrates, however, small freshwater fishes appear to have an equal or greater risk of extinction than large fishes. We explored whether particular traits explain the International Union for Conservation of Nature (IUCN) Red List conservation status of small‐bodied freshwater fishes from 4 temperate river basins: Murray‐Darling, Australia; Danube, Europe; Mississippi‐Missouri, North America; and the Rio Grande, North America. Twenty‐three ecological and life‐history traits were collated for all 171 freshwater fishes of ≤120 mm total length. We used generalized linear mixed‐effects models to assess which combination of the 23 traits best explained whether a species was threatened or not threatened. We used the best models to predict the probability of 29 unclassified species being listed as threatened. With and without controlling for phylogeny at the family level, small body size—among small‐bodied species—was the most influential trait correlated with threatened species listings. The k‐folds cross‐validation demonstrated that body size and a random effect structure that included family predicted the threat status with an accuracy of 78% (SE 0.5). We identified 10 species likely to be threatened that are not listed as such on the IUCN Red List. Small body size is not a trait that provides universal resistance to extinction, particularly for vertebrates inhabiting environments affected by extreme habitat loss and fragmentation. We hypothesize that this is because small‐bodied species have smaller home ranges, lower dispersal capabilities, and heightened ecological specialization relative to larger vertebrates. Trait data and further model development are needed to predict the IUCN conservation status of the over 11,000 unclassified freshwater fishes, especially those under threat from proposed dam construction in the world's most biodiverse river basins. 相似文献
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Solar energy conversion into electricity by photovoltaic modules is now a mature technology. We discuss the need for materials and device developments using conventional silicon and other materials, pointing to the need to use scalable materials and to reduce the energy payback time. Storage of solar energy can be achieved using the energy of light to produce a fuel. We discuss how this can be achieved in a direct process mimicking the photosynthetic processes, using synthetic organic, inorganic, or hybrid materials for light collection and catalysis. We also briefly discuss challenges and needs for large-scale implementation of direct solar fuel technologies. 相似文献
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Kasim A. Korkmaz Ali SariAsuman I. Carhoglu 《Journal of Loss Prevention in the Process Industries》2011,24(4):314-320
In 1999, two earthquakes in northwest Turkey caused heavy damage to a large number of industrial facilities. This region is the most industrialized in the country, and heavy damage has a significant economic influence. Industrial storage tanks, ruptured by earthquakes, exascerbate damage through the spread of fire. Storage tanks are uniquely structured, tall cylindrical vessels, some supported by relatively short reinforced concrete columns. The main aim of this study is to evaluate the earthquake performance of Turkish industrial facilities, especially storage tanks in terms of earthquake resistance. Modeling a typical storage tank of an industrial facility helps to understand the structure’s seismic response. A model tank structure was modelled as a solid with lumped mass and spring systems. Performance estimation was done with 40 different earthquake data through nonlinear time history analyses. After the time history analyses, fragility analyses produced probabilistic seismic assessment for the tank model. For the model structure, analysis results were evaluated and compared. In the study, vulnerability of storage tanks in Turkey was determined and the probabilistic risk was defined with the results of the analysis. 相似文献
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随着中国经济高速发展,污染物排放量大幅增长,水环境中的氨氮污染问题也已成为水环境治理的关注焦点.文章分别从源头削减和末端治理两个层面介绍了中国工业、农业、城镇生活源氨氮减排的技术的发展,氨氮减排技术为氨氮污染防控工作提供了科学、合理、有效的技术和理论支撑;从政策体制方面介绍了氨氮减排现状和要求,对氨氮减排技术及氨氮减排体制在中国的发展提出了相应的展望,为进一步发展和完善氨氮减排工作提供借鉴和参考.同时,也为未来氨氮污染物排放总量减排会进一步向智能化、精细化发展,氨氮减排技术在减排体制中体现的支撑作用. 相似文献
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Carlos Carroll Brett Hartl Gretchen T. Goldman Daniel J. Rohlf Adrian Treves Jeremy T. Kerr Euan G. Ritchie Richard T. Kingsford Katherine E. Gibbs Martine Maron James E. M. Watson 《Conservation biology》2017,31(5):967-975
Government agencies faced with politically controversial decisions often discount or ignore scientific information, whether from agency staff or nongovernmental scientists. Recent developments in scientific integrity (the ability to perform, use, communicate, and publish science free from censorship or political interference) in Canada, Australia, and the United States demonstrate a similar trajectory. A perceived increase in scientific‐integrity abuses provokes concerted pressure by the scientific community, leading to efforts to improve scientific‐integrity protections under a new administration. However, protections are often inconsistently applied and are at risk of reversal under administrations publicly hostile to evidence‐based policy. We compared recent challenges to scientific integrity to determine what aspects of scientific input into conservation policy are most at risk of political distortion and what can be done to strengthen safeguards against such abuses. To ensure the integrity of outbound communications from government scientists to the public, we suggest governments strengthen scientific integrity policies, include scientists’ right to speak freely in collective‐bargaining agreements, guarantee public access to scientific information, and strengthen agency culture supporting scientific integrity. To ensure the transparency and integrity with which information from nongovernmental scientists (e.g., submitted comments or formal policy reviews) informs the policy process, we suggest governments broaden the scope of independent reviews, ensure greater diversity of expert input and transparency regarding conflicts of interest, require a substantive response to input from agencies, and engage proactively with scientific societies. For their part, scientists and scientific societies have a responsibility to engage with the public to affirm that science is a crucial resource for developing evidence‐based policy and regulations in the public interest. 相似文献