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991.
992.
不同热解及来源生物炭对西北黄土吸附敌草隆的影响 总被引:3,自引:1,他引:2
以西北黄土为研究对象,采用批量法研究不同温度下制得的生物炭对西北黄土吸附敌草隆的影响.结果表明,敌草隆在添加不同质生物炭黄土上的动力学吸附过程较好地符合准二级吸附动力学模型,且吸附过程主要分为快吸附(0~8 h)和慢吸附(8~12 h)两个阶段,在12 h左右达到平衡;热力学较好地符合Freundlich等温吸附模型;添加生物炭的黄土对敌草隆的吸附量随着温度的升高而增大,且吸附过程中ΔG~θ小于0,ΔH~θ和ΔS~θ大于0;不加生物炭的黄土对敌草隆吸附量则随着温度的升高而降低,且吸附过程中ΔG~θ和ΔH~θ小于0,ΔS~θ大于0;在体系温度范围内,E(吸附平均自由能)为1.29~5.00 k J·mol-1,表明无论是否添加生物炭,黄土对敌草隆的吸附都以物理吸附为主.其影响因素分析结果显示,随着生物炭热解温度的升高,溶液中敌草隆的平衡浓度降低,平衡吸附量增大;添加生物炭的黄土对敌草隆吸附量在0.5~6 mg·L-1浓度范围内快速上升,之后吸附量随初始浓度的升高缓慢增加并逐渐趋于平衡;溶液pH对黄土吸附敌草隆有一定影响,但影响不大. 相似文献
993.
Richard J. Ladle João V. L. Firmino Ana C. M. Malhado Armando Rodríguez‐Durán 《Conservation biology》2012,26(6):978-982
The term hot cave is used to describe some subterranean chambers in the Neotropics that are characterized by constantly high ambient temperatures generated by the body heat of high densities of certain bat species. Many of these species have limited geographic ranges, and some occur only in the hot‐cave environment. In addition to the bats, the stable microclimate and abundant bat guano provides refuge and food for a high diversity of invertebrates. Hot caves have so far been described in the Caribbean and in a few isolated locations from Mexico to Brazil, although there is some evidence that similar caves may be present throughout the tropics. The existing literature suggests these poorly known ecosystems, with their unique combination of geomorphology and bat‐generated microclimate, are particularly sensitive to disturbance and face multiple threats from urbanization, agricultural development, mining, and tourism. Diversidad No Explorada y Potencial de Conservación de Cuevas Neotropicales Calientes 相似文献
994.
P. VISCONTI M. DI MARCO J. G. ÁLVAREZ‐ROMERO S. R. JANUCHOWSKI‐HARTLEY R. L. PRESSEY R. WEEKS C. RONDININI 《Conservation biology》2013,27(5):1000-1010
Data on the location and extent of protected areas, ecosystems, and species’ distributions are essential for determining gaps in biodiversity protection and identifying future conservation priorities. However, these data sets always come with errors in the maps and associated metadata. Errors are often overlooked in conservation studies, despite their potential negative effects on the reported extent of protection of species and ecosystems. We used 3 case studies to illustrate the implications of 3 sources of errors in reporting progress toward conservation objectives: protected areas with unknown boundaries that are replaced by buffered centroids, propagation of multiple errors in spatial data, and incomplete protected‐area data sets. As of 2010, the frequency of protected areas with unknown boundaries in the World Database on Protected Areas (WDPA) caused the estimated extent of protection of 37.1% of the terrestrial Neotropical mammals to be overestimated by an average 402.8% and of 62.6% of species to be underestimated by an average 10.9%. Estimated level of protection of the world's coral reefs was 25% higher when using recent finer‐resolution data on coral reefs as opposed to globally available coarse‐resolution data. Accounting for additional data sets not yet incorporated into WDPA contributed up to 6.7% of additional protection to marine ecosystems in the Philippines. We suggest ways for data providers to reduce the errors in spatial and ancillary data and ways for data users to mitigate the effects of these errors on biodiversity assessments. Efectos de Errores y Vacíos en Conjuntos de Datos Espaciales sobre la Evaluación del Progreso de la Conservación 相似文献
995.
Salah A. Soliman Nabila S. Ahmed Kawther S. El‐Gendy Ahmed S. El‐Bakary Abd‐El‐Khalek H. El‐Sebae 《Journal of environmental science and health. Part. B》2013,48(5):401-411
Abstract The susceptibility of wild mallard ducklings to the delayed neurotoxic effect of the neurotoxic organophosphorus insecticides cyanofenphos and leptophos was evaluated following a daily dosing regimen. Ducklings were treated daily with either cyanofenphos or with leptophos at different dose levels for 90 days, or until they died, or became paralyzed. A control group of ducklings given corn oil at 1 ml/kg daily for 90 days was used for comparison. All treated birds were observed daily for any clinical signs of neurotoxicity during the course of this study. All of the surviving ducklings that were treated with cyanofenphos at 4 mg/kg/day or leptophos at 10 mg/kg/day developed clinical signs of delayed neurotoxicity after 7 to 11 weeks of intoxication. Symptoms included leg weakness, ataxia, severe ataxia and paralysis. The observed clinical signs were confirmed by histological changes found in the spinal cords of the treated birds. These changes were of the type associated with organophosphorus‐induced delayed neuropathy (OPIDN). These results demonstrate that wild mallard ducklings are susceptible to OPIDN and this avian species can be used in screening organophos‐phorus compounds for such effect. 相似文献
996.
997.
YOAN PAILLET LAURENT BERGÈS JOAKIM HJÄLTÉN PÉTER ÓDOR CATHERINE AVON MARKUS BERNHARDT‐RÖMERMANN RIENK‐JAN BIJLSMA LUC DE BRUYN MARC FUHR ULF GRANDIN ROBERT KANKA LARS LUNDIN SANDRA LUQUE TIBOR MAGURA SILVIA MATESANZ ILONA MÉSZÁROS M.‐TERESA SEBASTIÀ WOLFGANG SCHMIDT TIBOR STANDOVÁR BÉLA TÓTHMÉRÉSZ ANNELI UOTILA FERNANDO VALLADARES KAI VELLAK RISTO VIRTANEN 《Conservation biology》2010,24(4):1157-1160
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999.
Abstract: Modern global temperature and land cover and projected future temperatures suggest that tropical forest species will be particularly sensitive to global warming. Given a moderate greenhouse gas emissions scenario, fully 75% of the tropical forests present in 2000 will experience mean annual temperatures in 2100 that are greater than the highest mean annual temperature that supports closed‐canopy forest today. Temperature‐sensitive species might extend their ranges to cool refuges, defined here as areas where temperatures projected for 2100 match 1960s temperatures in the modern range. Distances to such cool refuges are greatest for equatorial species and are particularly large for key tropical forest areas including the Amazon and Congo River Basins, West Africa, and the upper elevations of many tropical mountains. In sum, tropical species are likely to be particularly sensitive to global warming because they are adapted to limited geographic and seasonal variation in temperature, already lived at or near the highest temperatures on Earth before global warming began, and are often isolated from cool refuges. To illustrate these three points, we examined the distributions and habitat associations of all extant mammal species. The distance to the nearest cool refuge exceeded 1000 km for more than 20% of the tropical and less than 4% of the extratropical species with small ranges. The biological impact of global warming is likely to be as severe in the tropics as at temperate and boreal latitudes. 相似文献
1000.
中国未来20年资源与环境技术预见研究 总被引:1,自引:0,他引:1
阐述了技术预见的定义和发展,对中国科学院知识创新工程重要方向项目"中国未来20年技术预见研究"中资源与环境技术领域的德尔菲调查结果进行了概要介绍和系统分析,得出了一些初步结论:①"深海油气与矿产资源开采技术得到广泛应用"在综合重要度中名列第一;②从技术课题的预期实现时间分布来看.主要集中在2015-2020年;③我国资源与环境领域技术的总体研究水平远远低于国际水平,只有少量技术课题具有世界可比性;④普遍认为美国是当前资源与环境领域技术领先国家,美国、欧盟和日本三者基本上占据了资源与环境技术领域领先的主要领域;⑤从技术发展制约因素来看,"研究开发投入"因素影响最大.其后依次是"技术可能性"、"法规、政策和标准"、"基础设施"、"人力资源"和"商业可行性".文章最后提出了若干政策建议. 相似文献