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991.
Al-Khashman OA 《Environmental geochemistry and health》2007,29(1):1-10
Street dust samples (120 in total) were collected under stable weather conditions during the hot, dry season (August and September)
of 2004 from six different localities (industrial, heavy traffic, medium traffic, light traffic, low traffic and rural) in
greater Amman, the capital of Jordan. The concentrations of Fe, Cu, Cd, Pb, Zn and Ni in the dusts were determined by atomic
absorption spectrophotometry. The high concentrations of Pb, Fe and Zn in the street dust samples were related to both anthropogenic
(industrial sources combined with traffic sources) and natural sources. Surprisingly, the concentrations of Cd in the dusts
were low. Correlation coefficient analysis and principle component analysis identified three main sources of these elements
and the corresponding distributions. The elements Pb, Zn, Cd, Fe, Cu and Ni were mainly derived from industrial sources, with
Pb and Zn additionally derived from traffic sources. The street dusts were found to have highly elevated levels of Zn, particularly
along the main trunk roads, indicating that the Zn in the street dusts may be derived from traffic sources, especially vehicle
tyres. The concentrations of metals in the different street dust samples were found to vary depending on the density of traffic. 相似文献
992.
993.
994.
畜禽养殖污染是不容忽视的新的环境问题 总被引:5,自引:0,他引:5
本文论述了畜禽养殖业对环境带来的污染已成为新的环境问题,并提出了改进的措施。 相似文献
995.
996.
River damming provides a dominant human impact on river environments worldwide, and while local impacts of reservoir flooding
are immediate, subsequent ecological impacts downstream can be extensive. In this article, we assess seven research strategies
for analyzing the impacts of dams and river flow regulation on riparian ecosystems. These include spatial comparisons of (1)
upstream versus downstream reaches, (2) progressive downstream patterns, or (3) the dammed river versus an adjacent free-flowing
or differently regulated river(s). Temporal comparisons consider (4) pre- versus post-dam, or (5) sequential post-dam conditions.
However, spatial comparisons are complicated by the fact that dams are not randomly located, and temporal comparisons are
commonly limited by sparse historic information. As a result, comparative approaches are often correlative and vulnerable
to confounding factors. To complement these analyses, (6) flow or sediment modifications can be implemented to test causal
associations. Finally, (7) process-based modeling represents a predictive approach incorporating hydrogeomorphic processes
and their biological consequences. In a case study of Hells Canyon, the upstream versus downstream comparison is confounded
by a dramatic geomorphic transition. Comparison of the multiple reaches below the dams should be useful, and the comparison
of Snake River with the adjacent free-flowing Salmon River may provide the strongest spatial comparison. A pre- versus post-dam
comparison would provide the most direct study approach, but pre-dam information is limited to historic reports and archival
photographs. We conclude that multiple study approaches are essential to provide confident interpretations of ecological impacts
downstream from dams, and propose a comprehensive study for Hells Canyon that integrates multiple research strategies. 相似文献
997.
Because American national forests are managed for all citizens, it is important that researchers explore the differences and
similarities between citizens living both near and far from publicly managed land. We surveyed residents living at various
distances from nationally managed land to collect resident perceptions of different forest fire-management techniques, to
determine public preferences for these techniques, and to examine the motivations behind these preferences. Participants both
close to and far away from national forests tended to favor a multipronged approach to fire management by preferring the use
of a combination of two or more fire-management techniques. There were no significant differences by proximity in participants’
self-rated emotions, types of fire-management techniques preferred, or the reasons and rationales for their preferred fire-management
technique(s), indicating that the proximity variable may not be as significant as previously thought. 相似文献
998.
Perceiving the Environment from the Lay Perspective in Desertified Areas,Northern China 总被引:1,自引:0,他引:1
Investigating local people’s environmental perceptions can produce useful information that could be incorporated into decision
making processes that help resolve environmental problems. Although China is undergoing severe desertification, the perceptions
of the local people toward their degraded environment and the related issues have so far not been actively solicited. This
article, which is a supplement to Lee and Zhang’s (2004, 2005) studies, seeks to further investigate the lay public’s general environmental attitudes, perceptions of desertification, interpretations
of land-degrading activities, and particularly their interrelations in severely desertified areas. Minqin County in Gansu
Province, northern China, was chosen to be the study area. Data was collected via a questionnaire survey (n = 1138) administered in December 2002. Major findings were: (1) Most respondents had only weak altruistic environmental attitudes,
with educational level to be a significant determinant. (2) Respondents’ perceptions of desertification and interpretations
of land-degrading activities were contingent on personal attributes, general environmental attitudes, and other conceptions
related to desertification. It is recommended that the interrelations between the various aspects of the public’s environmental
perceptions should be thoroughly examined to facilitate their participation in environmental management. 相似文献
999.
Lobpreis T Vrana B Dominiak E Dercová K Mills GA Greenwood R 《Environmental pollution (Barking, Essex : 1987)》2008,153(3):706-710
Passive sampling of pollutants in water has been gaining acceptance for environmental monitoring. Previously, an integrative passive sampler (the Chemcatcher) was developed and calibrated for the measurement of time weighted average concentrations of hydrophobic pollutants in water. Effects of physicochemical properties and environmental variables (water temperature and turbulence) on kinetic and thermodynamic parameters characterising the exchange of analytes between the sampler and water have been published. In this study, the effect of modification in sampler housing geometry on these calibration parameters was studied. The results obtained for polycyclic aromatic hydrocarbons show that reducing the depth of the cavity in the sampler body geometry increased the exchange kinetics by approximately twofold, whilst having no effect on the correlation between the uptake and offload kinetics of analytes. The use of performance reference compounds thus avoids the need for extensive re-calibration when the sampler body geometry is modified. 相似文献
1000.
Del-Pilar-Ruso Y De-la-Ossa-Carretero JA Giménez-Casalduero F Sánchez-Lizaso JL 《Environmental pollution (Barking, Essex : 1987)》2008,156(2):240-250
Desalination is a growing activity that has introduced a new impact, brine discharge, which may affect benthic communities. Although the role of polychaetes as indicators to assess organic pollution is well known, their tolerance to salinity changes has not been examined to such a great extent. The aim of this study was to examine the effect of brine discharge over soft bottom polychaete assemblage along the Alicante coast (Southeast Spain) over a two year period. Changes in the polychaete assemblage was analysed using univariate and multivariate techniques. We compared a transect in front of the discharge with two controls. At each transect we sampled at three depths (4, 10 and 15 m) during winter and summer. We have observed different sensitivity of polychaete families to brine discharges, Ampharetidae being the most sensitive, followed by Nephtyidae and Spionidae. Syllidae and Capitellidae showed some resistance initially, while Paraonidae proved to be a tolerant family. 相似文献