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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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RODOLFO JAFFÉ VINCENT DIETEMANN MIKE H. ALLSOPP CECILIA COSTA ROBIN M. CREWE RAFFAELE DALL’OLIO PILAR DE LA RÚA MOGBEL A. A. EL‐NIWEIRI INGEMAR FRIES NIKOLA KEZIC MICHAEL S. MEUSEL ROBERT J. PAXTON TAHER SHAIBI ECKART STOLLE ROBIN F.A. MORITZ 《Conservation biology》2010,24(2):583-593
Abstract: Although pollinator declines are a global biodiversity threat, the demography of the western honeybee (Apis mellifera) has not been considered by conservationists because it is biased by the activity of beekeepers. To fill this gap in pollinator decline censuses and to provide a broad picture of the current status of honeybees across their natural range, we used microsatellite genetic markers to estimate colony densities and genetic diversity at different locations in Europe, Africa, and central Asia that had different patterns of land use. Genetic diversity and colony densities were highest in South Africa and lowest in Northern Europe and were correlated with mean annual temperature. Confounding factors not related to climate, however, are also likely to influence genetic diversity and colony densities in honeybee populations. Land use showed a significantly negative influence over genetic diversity and the density of honeybee colonies over all sampling locations. In Europe honeybees sampled in nature reserves had genetic diversity and colony densities similar to those sampled in agricultural landscapes, which suggests that the former are not wild but may have come from managed hives. Other results also support this idea: putative wild bees were rare in our European samples, and the mean estimated density of honeybee colonies on the continent closely resembled the reported mean number of managed hives. Current densities of European honeybee populations are in the same range as those found in the adverse climatic conditions of the Kalahari and Saharan deserts, which suggests that beekeeping activities do not compensate for the loss of wild colonies. Our findings highlight the importance of reconsidering the conservation status of honeybees in Europe and of regarding beekeeping not only as a profitable business for producing honey, but also as an essential component of biodiversity conservation. 相似文献
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MARZIO BABILLE PIERPAOLO DE COLOMBANI RANIERI GUERRA NEVIO ZAGARIA CHIARA ZANETTI 《Disasters》1994,18(1):58-75
In 1991 a computerized, comprehensive epidemiological surveillance system was developed to monitor health trends in approximately 25,000 acutely displaced Kurds in Nowsood and Saryas refugee camps, Bakhtaran region, Northwestern Iran. In addition, community-based surveys offered information unobtainable from health facilities. Weekly population movements, attack rates, point-prevalence estimates, and case fatality ratios were calculated, and the data were analysed and compared. The overall crude mortality rate (CMR) in the camps under study was still 9 times higher than the reported CMR for Iraq. Health problems with very low rates (less than 1.0/ 1,000 population/week) included the triad of measles, meningitis and tetanus. However, morbidity for the most common conditions (acute respiratory infections, diarrhoea, skin infections, eye diseases and, finally, typhoid fever) was shown to increase at the end of the intervention, highlighting that the pressure of repatriation on refugees made them progressively worse. This article concludes that epidemiological surveillance systems should be implemented during mass-migrations in developing countries also in post-emergency settings. Furthermore, surveillance appears to be indispensable in order for the international agencies to keep abreast of events and to safeguard human rights when international attention subsides. 相似文献
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S.R. Utembe L.A. Watson D.E. Shallcross M.E. Jenkin 《Atmospheric environment (Oxford, England : 1994)》2009,43(12):1982-1990
A Photochemical Trajectory Model (PTM), containing the Master Chemical Mechanism version 3.1 (MCM v3.1) coupled with an optimised representation of gas–aerosol absorptive partitioning of 365 oxygenated product species, has been used to simulate mass concentrations of secondary organic aerosol (SOA) for the conditions of the TORCH-2003 campaign in the south-east UK in late July and August 2003. A comprehensive reference dataset of 50 case study arrival events (and 4750 associated hourly air mass history events) has been compiled, which considers the base case conditions and scenarios in which emissions of anthropogenic pollution have been reduced by factors of up to 100. The relative contributions of SOA derived from anthropogenic and biogenic precursors are presented for the range of conditions, and the composition of these simulated components is discussed in terms of average molecular formulae, atomic ratios (H/C, O/C and N/C) and organic aerosol mass to organic carbon mass ratios (OM/OC), which are compared to reported measurements. The MCM v3.1 dataset has been used as a reference benchmark for development and optimisation of a reduced (14 species) SOA module for use with version 2 the Common Representative Intermediates mechanism (CRI v2), described in the first of two preceding companion papers [Jenkin, M.E., Watson, L.A., Utembe, S.R., Shallcross, D.E., 2008a. A Common Representative Intermediates (CRI) mechanism for VOC degradation. Part 1: gas phase mechanism development. Atmospheric Environment, 42, pp. 7185–7195. doi:10.1016/j.atmosenv.2008.07.028.]. The resultant version of the PTM containing CRI v2 and the reduced SOA module has been used to simulate the entire TORCH-2003 campaign at hourly resolution, and the contributions of SOA derived from anthropogenic and biogenic precursors are presented and discussed. The reduced SOA module is also shown to be compatible with the most reduced CRI variant (CRI v2-R5), described in the second of two preceding companion papers [Watson, L.A., Shallcross, D.E., Utembe, S.R., Jenkin, M.E., 2008. A Common Representative Intermediates (CRI) mechanism for VOC degradation. Part 2: gas phase mechanism reduction. Atmospheric Environment, 42, pp. 7196–7204. doi:10.1016/j.atmosenv.2008.07.034.], which is considered appropriate as a traceable reference mechanism in global simulations. 相似文献
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Polluting substances are spread as a consequence of the construction and use of roads. This article provides a summary of
the substances with which traffic pollutes the environment on a local, regional and global level. The mechanisms of dispersion
of pollutants to soil and groundwater are described. Based on environmental quality requirements established in rules and
regulations in the Netherlands, the paper discusses mitigating measures necessary to limit the distribution of pollutants
along highways. Most of the data in this article come from original research carried out by or by order of the Road and Hydraulic
Institute. For comparison, other data from the Netherlands have been included. It is shown that source-oriented measures (volume
and technical) will have more effect on environmental quality than measures with regard to treating runoff. The use of porous
asphalt instead of nonporous asphalt on highways in the Netherlands has environmental benefits. The article also pays attention
to combined use of the roadside verges for treatment of runoff using ecological engineering techniques in the form of natural
processes in helophyte filter systems in combination with enhancement of ecological values along highways. 相似文献
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RÔMULO ROMEU DA NÓBREGA ALVES GENTIL ALVES PEREIRA FILHO YURI CLÁUDIO CORDEIRO DE LIMA 《Environment, Development and Sustainability》2007,9(4):455-464
This paper documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the States of Maranhão and Paraíba, where dwellers provided information on snake species used as medicine, body parts used to prepare the remedies, and the illnesses to which the remedies were prescribed. The species used as medicinal drug and their respective families were: Crotalus durissus (rattlesnake), Bothrops leucurus (‘lance head’, a venomous snake), and Lachesis muta (bushmaster) of the family Crotalidae; and Boa constrictor (boa constrictor), Epicrates cenchria (‘salamanta’), and Eunectes murinus (anaconda) of the family (Boidae). These zootherapeutical resources were used for the cure of 14 illnesses. The most commonly cited species were Crotalus durissus (n=26) e Boa constrictor (n=6), Apparently, the medicinal use of snakes does not pose a threat for their population in the studied sites. 相似文献
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Ido DE Groot 《Journal of the Air & Waste Management Association (1995)》2013,63(10):679-681
This paper attempts to bring together the findings relative to people’s attitudes about air pollution from a series of studies conducted by or for the U. S. Public Health Service. Trends are noted. These findings are presented in the light of planning for the implementation of air pollution abatement measures and probable public reactions to them. Further research needs are pointed out. Special emphasis is placed on the control officer’s needs for this type of information, its derivation, and its possible use in programming. 相似文献