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61.
Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación 相似文献
62.
莱州湾水体中有机磷农药的残留监测与风险影响评价 总被引:5,自引:0,他引:5
研究近年来莱州湾水体中有机磷农药残留情况及对环境的影响.于2005年5月采集了渤海莱州湾及其主要河口地区的水样,用气相色谱(GC-FPD)测定了样品中有机磷农药的含量,并运用化学污染物风险评价公式进行了风险概率评价.结果表明,莱州湾海域水体中有机磷农药的含量范围在0.2~79.1 ng/L,氧化乐果、甲胺磷、马拉硫磷、敌百虫、敌敌畏、乐果、甲基毒死蜱、甲基对硫磷等在研究海域占主要部分.对研究海域水体中有机磷农药的风险评价表明,莱州湾海域水体中的有机磷农药的含量与其他地区相比,污染水平居中,氧化乐果、甲胺磷、马拉硫磷、敌百虫、敌敌畏、乐果等农药对研究海域的生态环境安全已经构成了一定的威胁,应加强该地区该类农药的施用管理. 相似文献
63.
零价铁降解4-氯硝基苯动力学研究 总被引:8,自引:3,他引:5
实验采用无氧条件下不同浓度零价铁降解硝基芳香烃代表物4-氯硝基苯,研究4-氯硝基苯的降解速率及各产物的反应速率.根据化学反应计量学,通过准一级动力学方程对实验结果进行拟合,得到生成各产物反应速率,并利用穆斯堡尔技术检测零价铁的产物.结果表明,4-氯硝基苯的还原转化速率与零价铁浓度有关,中间产物4-氯亚硝基苯和4-氯苯基羟胺的生成和转化速率可通过拟合各反应速率得到.当零价铁浓度为1.04 g.L-1时4-氯硝基苯反应速率最快,反应速率常数为0.189min-1.反应过程中生成的亚铁离子在反应初期吸附在零价铁表面,各物质的生成和还原速率取决于零价铁表面的活性位点和各物质与零价铁之间的质量传递. 相似文献
64.
生物炭添加对两种类型土壤DOC淋失影响 总被引:4,自引:0,他引:4
生物炭能增加土壤碳库贮量,对全球碳的生物地球化学循环和缓解全球气候变化起到不可忽视的作用。可溶性有机碳(DOC)是土壤碳库中十分重要的组分,研究生物炭对DOC淋失影响对深入了解生物炭对土壤有机碳循环具有重要意义。本文以新疆和河南两种土壤为对象,通过室内土柱淋滤试验研究生物炭添加对不同类型土壤中溶解性有机碳(DOC)淋失影响以及添加不同生物炭对同种土壤淋滤液中DOC淋失影响特征。结果表明,新疆和河南土壤淋滤液DOC浓度和淋失量随着生物炭添加比例增加(1%,5%,10%)而减少。与玉米秸秆和锯末混合物为原料制成生物炭相比,玉米秸秆生物炭能显著降低新疆土壤淋滤液中DOC浓度。 相似文献
65.
KATE A. HARDWICK PEGGY FIEDLER LYNDON C. LEE BRUCE PAVLIK RICHARD J. HOBBS JAMES ARONSON MARTIN BIDARTONDO ERIC BLACK DAVID COATES MATTHEW I. DAWS KINGSLEY DIXON STEPHEN ELLIOTT KERN EWING GEORGE GANN DAVID GIBBONS JOACHIM GRATZFELD MARTIN HAMILTON DAVID HARDMAN JIM HARRIS PAT M. HOLMES MEIRION JONES DAVID MABBERLEY ANDREW MACKENZIE CARLOS MAGDALENA ROBERT MARRS WILLIAM MILLIKEN ANTHONY MILLS EIMEAR NIC LUGHADHA MARGARET RAMSAY PAUL SMITH NIGEL TAYLOR CLARE TRIVEDI MICHAEL WAY OLIVER WHALEY STEPHEN D. HOPPER 《Conservation biology》2011,25(2):265-275
Abstract: Many of the skills and resources associated with botanic gardens and arboreta, including plant taxonomy, horticulture, and seed bank management, are fundamental to ecological restoration efforts, yet few of the world's botanic gardens are involved in the science or practice of restoration. Thus, we examined the potential role of botanic gardens in these emerging fields. We believe a reorientation of certain existing institutional strengths, such as plant‐based research and knowledge transfer, would enable many more botanic gardens worldwide to provide effective science‐based support to restoration efforts. We recommend botanic gardens widen research to include ecosystems as well as species, increase involvement in practical restoration projects and training practitioners, and serve as information hubs for data archiving and exchange. 相似文献
66.
HENRY LEE II DEBORAH A. REUSSER† JULIAN D. OLDEN‡ SCOTT S. SMITH† JIM GRAHAM§ VIRGINIA BURKETT JEFFREY S. DUKES†† ROBERT J. PIORKOWSKI‡‡ JOHN MCPHEDRAN§§ 《Conservation biology》2008,22(3):575-584
Abstract: Changes in temperature, precipitation, and other climatic drivers and sea-level rise will affect populations of existing native and non-native aquatic species and the vulnerability of aquatic environments to new invasions. Monitoring surveys provide the foundation for assessing the combined effects of climate change and invasions by providing baseline biotic and environmental conditions, although the utility of a survey depends on whether the results are quantitative or qualitative, and other design considerations. The results from a variety of monitoring programs in the United States are available in integrated biological information systems, although many include only non-native species, not native species. Besides including natives, we suggest these systems could be improved through the development of standardized methods that capture habitat and physiological requirements and link regional and national biological databases into distributed Web portals that allow drawing information from multiple sources. Combining the outputs from these biological information systems with environmental data would allow the development of ecological-niche models that predict the potential distribution or abundance of native and non-native species on the basis of current environmental conditions. Environmental projections from climate models can be used in these niche models to project changes in species distributions or abundances under altered climatic conditions and to identify potential high-risk invaders. There are, however, a number of challenges, such as uncertainties associated with projections from climate and niche models and difficulty in integrating data with different temporal and spatial granularity. Even with these uncertainties, integration of biological and environmental information systems, niche models, and climate projections would improve management of aquatic ecosystems under the dual threats of biotic invasions and climate change. 相似文献
67.
68.
Various air pollution control (APC) techniques were employed in order to reduce emissions of air pollutants produced from
chemical plants, which have many different chemical production facilities. For an emission reduction of acid gases, this study
employed a method to improve solubility of pollutants by decreasing the operating temperature of the scrubbers, increasing
the surface area for effective contact of gas and liquid, and modifying processes in the acid scrubbers. To reduce emission
of both amines and acid gases, pollutant gas components were first separated, then condensation and/or acid scrubbing, depending
on the chemical and physical properties of pollutant components, were used. To reduce emission of solvents, condensation and
activated carbon adsorption were employed. To reduce emission of a mixture gases containing acid gases and solvents, the mixed
gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower
in sequence. As a strategy to reduce emission of pollutants at the source, this study also employed the simple pollution prevention
concept of modification of the previously operating APC control device. Finally, air emissions of pollutants produced from
the chemical plants were much more reduced by applying proper APC methods, depending upon the types (physical or chemical
properties) and the specific emission situations of pollutants. 相似文献
69.
A laboratory sequential anaerobic aerobic bioreactor system, which consisted of an anaerobic fixed film reactor and two aerobic chemostats, was set up to degrade tetrachloroethylene (PCE) without accumulating highly toxic degradation intermediates. A soil enrichment culture, which could reductively dechlorinate 900μM (ca. 150 mg/L) of PCE stoichiometrically into cis-1,2-dichloroethylene ( cis-DCE), was attached to ceramic media in the anaerobic fixed film reactor. A phenol degrading strain, Alcaligenes sp. R5, which can efficiently degrade cis-DCE by co metabolic oxidation, was used as inoculum for the aerobic chemostats consisted of a transformation reactor and a growth reactor. The anaerobic fixed film bioreactor showed more than 99 % of PCE transformation into cis DCE in the range of influent PCE concentration from 5μM to 35μM at hydraulic retention time of 48h. On the other hand, efficient degradation of the resultant cis-DCE by strain R5 in the following aerobic system could not be achieved due to oxygen limitation. However, 54% of the maximum cis-DCE degradation was obtained when 10 μmol of hydrogen peroxide (H2O2) was supplemented to the transformation reactor as an additional oxygen source. Further studies are needed to achieve more efficient co metabolic degradation of cis DCE in the aerobic reactor. 相似文献
70.
LIU Wen-ju Kim Kyoung-woong ZHU Yong-guan LEE Sang-woo CHANG Pei-chun Kwak Ji-hyun 《环境科学学报(英文版)》2006,18(2):287-291
This research includes two investigations. The first one is a market basket survey of the levels of arsenic (As) and trace elements in bracken fern (Pteridium aquilinum) originated from three countries: South Korea, China and North Korea. The results showed that the mean As concentrations in stems of samples were significantly higher than those in leaves. As concentrations in all samples did not exceed food safety limits for vegetables. Generally, concentrations of Fe, Mn, Cu and Zn in leaves were higher than those in stems. The second investigation is a survey on the levels of As and other heavy metals in vegetation in the vicinity of Myoungbong mine tailings. The results demonstrated that As, Pb and Cu concentrations and bioaccumulation factors (BCF) in seedlings of the fern(A splenium achilleifolium) were the highest, whereas Marsh horsetail(Equisetum polustre) accumulated the highest levels of Zn. Concentrations of As, Pb, Zn and Cu in vegetable-cress (Lepidium sativum) and the edible herb-aromatic madder (Elasholtzia splendens) were higher than food safety limits. Therefore, a risk assessment of As and other heavy metals in vegetables and herbs on local human health should be conducted in the future. 相似文献