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951.
This article elaborates on and discusses gendered dimensions of climate change response in Swedish municipalities. There are indications that attitudes and behaviour to the environment and climate change are gendered. This evidence together with our own work further indicates that gender awareness is most probably an important influence on how municipalities respond to climate change. The aim of this study was to investigate if and how gendered aspects of climate change response are integrated in the Swedish response to climate change. The potential causal relationships between a high level of awareness of the gendered aspects of climate change and the levels of climate change response were investigated. We asked whether there is a positive relationship between gender awareness and the quality of the communities' climate change policies and practice. Indications of such a relationship prompt a change in research priorities – paying more attention to gender – and in subsequent policy developments. 相似文献
952.
Dean M. Gilligan Lynn M. Woodworth Margaret E. Montgomery David A. Briscoe & Richard Frankham 《Conservation biology》1997,11(5):1235-1241
The accumulation of new deleterious mutations has been predicted to constitute a significant threat to the survival of finite sexually reproducing populations. Three measures of genetic load were made on populations of Drosophila melanogaster maintained at effective population sizes of 25, 50, 100, 250, and 500 for 45 or 50 generations and their outbred base population and a new sample from the same wild population. Genetic loads were measured as fitness differentials between inbred and non-inbred lines derived from each population under both benign ( productivity of single pairs) and competitive (competitive index) conditions. No trend of smaller populations exhibiting greater genetic loads than larger ones was observed under either benign or competitive conditions. Further, genetic loads were similar in captive and wild populations. Frequencies of deleterious and lethal alleles on chromosome II were measured by making the chromosome (approximately 40% of the genome) homozygous using a marked balancer stock. Neither deleterious nor lethal allele frequencies exhibited a relationship with population size. The accumulation of detrimental mutations does not appear to pose a significant threat to finite sexual populations with effective sizes of 25 or more over the 100–200 year time frames considered in most wildlife conservation programs. 相似文献
953.
Dorothe Ehrich Niels M. Schmidt Gilles Gauthier Ray Alisauskas Anders Angerbjrn Karin Clark Frauke Ecke Nina E. Eide Erik Framstad Jay Frandsen Alastair Franke Olivier Gilg Marie-Andre Giroux Heikki Henttonen Birger Hrnfeldt Rolf A. Ims Gennadiy D. Kataev Sergey P. Kharitonov Siw T. Killengreen Charles J. Krebs Richard B. Lanctot Nicolas Lecomte Irina E. Menyushina Douglas W. Morris Guy Morrisson Lauri Oksanen Tarja Oksanen Johan Olofsson Ivan G. Pokrovsky Igor Yu. Popov Donald Reid James D. Roth Sarah T. Saalfeld Gustaf Samelius Benoit Sittler Sergey M. Sleptsov Paul A. Smith Aleksandr A. Sokolov Natalya A. Sokolova Mikhail Y. Soloviev Diana V. Solovyeva 《Ambio》2020,49(3):786-800
Lemmings are a key component of tundra food webs and changes in their dynamics can affect the whole ecosystem. We present a comprehensive overview of lemming monitoring and research activities, and assess recent trends in lemming abundance across the circumpolar Arctic. Since 2000, lemmings have been monitored at 49 sites of which 38 are still active. The sites were not evenly distributed with notably Russia and high Arctic Canada underrepresented. Abundance was monitored at all sites, but methods and levels of precision varied greatly. Other important attributes such as health, genetic diversity and potential drivers of population change, were often not monitored. There was no evidence that lemming populations were decreasing in general, although a negative trend was detected for low arctic populations sympatric with voles. To keep the pace of arctic change, we recommend maintaining long-term programmes while harmonizing methods, improving spatial coverage and integrating an ecosystem perspective. 相似文献
954.
He Chen Qiu Kaiyang Pott Richard 《Environmental science and pollution research international》2020,27(6):5825-5844
Environmental Science and Pollution Research - Particulate matter in European cities, especially in urban areas, is mainly from urban road traffic and constitutes a great threat to the health of... 相似文献
955.
Luke D. Knibbs Richard J. de Dear 《Atmospheric environment (Oxford, England : 1994)》2010,44(26):3224-3227
Concentrations of ultrafine (<0.1 μm) particles (UFPs) and PM2.5 (<2.5 μm) were measured whilst commuting along a similar route by train, bus, ferry and automobile in Sydney, Australia. One trip on each transport mode was undertaken during both morning and evening peak hours throughout a working week, for a total of 40 trips. Analyses comprised one-way ANOVA to compare overall (i.e. all trips combined) geometric mean concentrations of both particle fractions measured across transport modes, and assessment of both the correlation between wind speed and individual trip means of UFPs and PM2.5, and the correlation between the two particle fractions. Overall geometric mean concentrations of UFPs and PM2.5 ranged from 2.8 (train) to 8.4 (bus) × 104 particles cm?3 and 22.6 (automobile) to 29.6 (bus) μg m?3, respectively, and a statistically significant difference (p < 0.001) between modes was found for both particle fractions. Individual trip geometric mean concentrations were between 9.7 × 103 (train) and 2.2 × 105 (bus) particles cm?3 and 9.5 (train) to 78.7 (train) μg m?3. Estimated commuter exposures were variable, and the highest return trip mean PM2.5 exposure occurred in the ferry mode, whilst the highest UFP exposure occurred during bus trips. The correlation between fractions was generally poor, and in keeping with the duality of particle mass and number emissions in vehicle-dominated urban areas. Wind speed was negatively correlated with, and a generally poor determinant of, UFP and PM2.5 concentrations, suggesting a more significant role for other factors in determining commuter exposure. 相似文献
956.
Ana Isabel Miranda Vera Martins Pedro Cascão Jorge Humberto Amorim Joana Valente Richard Tavares Carlos Borrego Oxana Tchepel António Jorge Ferreira Carlos Robalo Cordeiro Domingos Xavier Viegas Luís Mário Ribeiro Luís Paulo Pita 《Environment international》2010,36(7):736-745
Forest fires represent a serious threat to public security in Europe due to the large burned area. Moreover, smoke pollution due to forest fire events is an important public health issue for the communities directly affected, and particularly for the personnel involved in firefighting operations. Aiming to contribute to the scientific knowledge concerning firefighters exposure to forest fires smoke, data of individual exposure to carbon monoxide, nitrogen dioxide, volatile organic compounds, and particulate matter were obtained during experimental field fires for a group of 10 firefighters equipped with portable “in continuum” measuring devices. Measured values are very high exceeding the Occupational Exposure Standard limits, in particular for peak limit thresholds. These are the first measurements and analysis of firefighter's individual exposure to toxic gases and particles in fire smoke experiments in Europe. However, they already indicate that urgent measures to avoid these levels of exposure are needed. 相似文献
957.
S. Kent Hoekman Amber Broch Curtis Robbins Richard Purcell 《International Journal of Greenhouse Gas Control》2010,4(1):44-50
A laboratory-scale reactor system was built and operated to demonstrate the feasibility of catalytically reacting carbon dioxide (CO2) with renewably-generated hydrogen (H2) to produce methane (CH4) according to the Sabatier reaction: CO2 + 4H2 → CH4 + 2H2O. A cylindrical reaction vessel packed with a commercial methanation catalyst (Haldor Topsøe PK-7R) was used. Renewable H2 produced by electrolysis of water (from solar- and wind-generated electricity) was fed into the reactor along with a custom blend of 2% CO2 in N2, meant to represent a synthetic exhaust mixture. Reaction conditions of temperature, flow rates, and gas mixing ratios were varied to determine optimum performance. The extent of reaction was monitored by real-time measurement of CO2 and CH4. Maximum conversion of CO2 occurred at 300–350 °C. Approximately 60% conversion of CO2 was realized at a space velocity of about 10,000 h?1 with a molar ratio of H2/CO2 of 4/1. Somewhat higher total CO2 conversion was possible by increasing the H2/CO2 ratio, but the most efficient use of available H2 occurs at a lower H2/CO2 ratio. 相似文献
958.
Canagaratna MR Onasch TB Wood EC Herndon SC Jayne JT Cross ES Miake-Lye RC Kolb CE Worsnop DR 《Journal of the Air & Waste Management Association (1995)》2010,60(10):1192-1203
Aerosol mass spectrometer (AMS) measurements are used to characterize the evolution of exhaust particulate matter (PM) properties near and downwind of vehicle sources. The AMS provides time-resolved chemically speciated mass loadings and mass-weighted size distributions of nonrefractory PM smaller than 1 microm (NRPM1). Source measurements of aircraft PM show that black carbon particles inhibit nucleation by serving as condensation sinks for the volatile and semi-volatile exhaust gases. Real-world source measurements of ground vehicle PM are obtained by deploying an AMS aboard a mobile laboratory. Characteristic features of the exhaust PM chemical composition and size distribution are discussed. PM mass and number concentrations are used with above-background gas-phase carbon dioxide (CO2) concentrations to calculate on-road emission factors for individual vehicles. Highly variable ratios between particle number and mass concentrations are observed for individual vehicles. NRPM1 mass emission factors measured for on-road diesel vehicles are approximately 50% lower than those from dynamometer studies. Factor analysis of AMS data (FA-AMS) is applied for the first time to map variations in exhaust PM mass downwind of a highway. In this study, above-background vehicle PM concentrations are highest close to the highway and decrease by a factor of 2 by 200 m away from the highway. Comparison with the gas-phase CO2 concentrations indicates that these vehicle PM mass gradients are largely driven by dilution. Secondary aerosol species do not show a similar gradient in absolute mass concentrations; thus, their relative contribution to total ambient PM mass concentrations increases as a function of distance from the highway. FA-AMS of single particle and ensemble data at an urban receptor site shows that condensation of these secondary aerosol species onto vehicle exhaust particles results in spatial and temporal evolution of the size and composition of vehicle exhaust PM on urban and regional scales. 相似文献
959.
960.
Annika Åberg Mats Tysklind Tohr Nilsson Matthew MacLeod Annika Hanberg Rolf Andersson Sture Bergek Richard Lindberg Karin Wiberg 《Environmental science and pollution research international》2010,17(1):26-39