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421.
422.
Results of on-site interviews with industrial personnel involved in hearing conservation programs (HCPs) show common deficiencies in personnel training and program implementation, reducing HCP effectiveness in protecting employees from occupational hearing loss. Audiometric data base analysis (ADBA) provides procedures which allow HCP ineffectiveness to be detected before many employees develop significant noise-induced hearing loss. If HCP procedures are corrected, based on ADBA results, then audiometry serves to prevent hearing loss rather than simply detecting its occurrence. The paper presents criterion ranges for ADBA procedure results as recommended by the ANSI S12.12 Working Group for Evaluation of HCPs.  相似文献   
423.
We assessed the relationship between riparian management and stream quality along five southeastern Minnesota streams in 1995 and 1996. Specifically, we examined the effect of rotationally and continuously grazed pastures and different types of riparian buffer strips on water chemistry, physical habitat, benthic macroinvertebrates, and fish as indicators of stream quality. We collected data at 17 sites under different combinations of grazing and riparian management, using a longitudinal design on three streams and a paired watershed design on two others. Continuous and rotational grazing were compared along one longitudinal study stream and at the paired watershed. Riparian buffer management, fenced trees (wood buffer), fenced grass, and unfenced rotationally grazed areas were the focus along the two remaining longitudinal streams. Principal components analysis (PCA) of water chemistry, physical habitat, and biotic data indicated a local management effect. The ordinations separated continuous grazing from sites with rotational grazing and sites with wood buffers from those with grass buffers or rotationally grazed areas. Fecal coliform and turbidity were consistently higher at continuously grazed than rotationally grazed sites. Percent fines in the streambed were significantly higher at sites with wood buffers than grass and rotationally grazed areas, and canopy cover was similar at sites with wood and grass buffers. Benthic macroinvertebrate metrics were significant but were not consistent across grazing and riparian buffer management types. Fish density and abundance were related to riparian buffer type, rather than grazing practices. Our study has potentially important implications for stream restoration programs in the midwestern United States. Our comparisons suggest further consideration and study of a combination of grass and wood riparian buffer strips as midwestern stream management options, rather than universally installing wood buffers in every instance. RID=" ID=" The Unit is jointly sponsored by the US Geological Survey, Biological Resources Division; the Minnesota Department of Natural Resources; the University of Minnesota; and the Wildlife Management Institute.  相似文献   
424.
The purpose of this paper is to analyse under what conditions, with respect to CO2 emission-reduction and biofuels-for-transport targets, the trading in the EU of CO2 credits and solid and/or liquid biofuels is cost-effective from the perspective of an optimisation energy systems model. We use the PEEP model covering the EU27 (except Bulgaria, Malta, and Cyprus) to generate insights about the cost-effectiveness of different options under different policy scenarios. Trade in CO2 credits is a cost-effective option, in all relevant policy scenarios. Trade in some biofuels (mainly from central and eastern European countries to the EU15) is cost-effective in all assessed scenarios. In the case of CO2 targets (whether national or at the EU level) there is trade in solid biofuels. When biofuels-for-transport targets are also implemented, trading both solid and liquid biofuels is cost-effective.  相似文献   
425.
The above article from Disasters, published online on 24 June 2019 in Wiley Online Library ( http://wileyonlinelibrary.com ) has been withdrawn by agreement among the authors, the Journal editors and John Wiley & Sons Inc. on behalf of ODI. The withdrawal has been agreed because this is a duplicate of an article that has been published in Disasters Volume 44 Issue 1.  相似文献   
426.
Environmental Science and Pollution Research - Due to the development of the metallurgical and energy industries and the operation of incinerators, more and more environmental pollution is...  相似文献   
427.
Abstract

European cities have emerged as laboratories for ‘sustainable mobility'. In the last few years, they have supported numerous electric car projects which combine clean engine technologies with offers on public or shared mobility. This paper compares two ongoing public electric car services in Berlin (BeMobility) and Paris (Autolib’). We explain how both projects shape future visions of sustainable mobility and transform regional transport systems in specific ways through their performative impact as local transport policy tools. Focusing on the socio-economic and political processes through which both projects were conceived and put into practice, we explain their differences as they reflect participating actors' interests in a French versus German industrial and transport policy context after the economic crisis in 2008. We find that whereas BeMobility integrates electric cars as one element in Berlin's intermodal transport system, and thus is centred around ‘intermodality' as the central vision of sustainable transport, Autolib’ in Paris essentially reproduces the dominant mode of private passenger car transport through adding a shared electric car fleet.  相似文献   
428.
It has been suggested that differences in body size between consumer and resource species may have important implications for interaction strengths, population dynamics, and eventually food web structure, function, and evolution. Still, the general distribution of consumer-'resource body-size ratios in real ecosystems, and whether they vary systematically among habitats or broad taxonomic groups, is poorly understood. Using a unique global database on consumer and resource body sizes, we show that the mean body-size ratios of aquatic herbivorous and detritivorous consumers are several orders of magnitude larger than those of carnivorous predators. Carnivorous predator-prey body-size ratios vary across different habitats and predator and prey types (invertebrates, ectotherm, and endotherm vertebrates). Predator-prey body-size ratios are on average significantly higher (1) in freshwater habitats than in marine or terrestrial habitats, (2) for vertebrate than for invertebrate predators, and (3) for invertebrate than for ectotherm vertebrate prey. If recent studies that relate body-size ratios to interaction strengths are general, our results suggest that mean consumer-resource interaction strengths may vary systematically across different habitat categories and consumer types.  相似文献   
429.
Green ID  Jeffries C  Diaz A  Tibbett M 《Chemosphere》2006,64(7):1115-1121
This study investigates the transfer of Cd and Zn from a soil amended with sewage sludge at rates up to 100 t ha(-1) through a multi-trophic system consisting of barley, the aphid Sitobion avenae and the larvae of the lacewing Chrysoperla carnae. Results show marked differences in the transfer of the two metals. Cadmium was freely accumulated in barley roots, but accumulation in the shoot was restricted to a concentration of around 0.22 mg kg(-1) (dry weight). This limited the transfer of Cd to higher trophic levels and resulted in no significant accumulation of Cd in S. avenae or in C. carnae. Zinc transfer in the system was largely unrestricted, resulting in significant accumulation in roots and shoots, in S. avenae and in C. carnae. Cadmium biomagnification occurred in lacewing pupae, with concentrations up to 3.6 times greater than in aphids. S. avenae biomagnified Zn by a factor of ca. 2.5 at low sludge amendment rates, but biomagnification decreased to a factor of 1.4 at the highest amendment rate. Biomagnification of Zn did not occur in C. carnae, but concentrations were up to 3.5 time higher than in soil. Results are discussed in light of the mechanisms regulating transfer of the two metals in the system.  相似文献   
430.
Understanding how human modification of the landscape shapes vertebrate community composition is vital to understanding the current status and future trajectory of wildlife. Using a participatory approach, we deployed the largest camera-trap network in Mesoamerica to date to investigate how anthropogenic disturbance shapes the occupancy and co-occurrence of terrestrial vertebrate species in a tropical biodiversity hotspot: the Osa Peninsula, Costa Rica. We estimated species richness in different categories of land protection with rarefaction analysis and estimated the expected occupancy with a joint species distribution model that included covariates for anthropogenic disturbance, land protection, habitat quality, and habitat availability. Areas with the most stringent land-use protections (e.g., Corcovado National Park, 24 species [95% CI 23–25]) harbored significantly more species than unprotected areas (20 species [19.7–20.3]), mainly due to a reduced presence of large-bodied species of conservation concern in unprotected areas (e.g., jaguar Panthera onca and white-lipped peccary Tayassu pecari). Small-bodied generalist species, such as opossums (Didelphidae) and armadillos (Dasypus novemcinctus), in contrast, were more common at disturbed sites, resulting in a significant difference in vertebrate community composition between sites with low and high disturbance. Co-occurrence of species was also mainly associated with response to disturbance. Similar responses to disturbance create two groups of species, those whose site-level occupancy usually increased as anthropogenic disturbance increased and those whose estimated occupancy decreased. The absence of large-bodied species entails an important loss of ecological function in disturbed areas and can hinder forest development and maintenance. Efforts to protect and restore forested landscapes are likely having a positive effect on the abundance of some threatened species. These efforts, however, must be sustained and expanded to increase connectivity and ensure the long-term viability of the wildlife community.  相似文献   
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