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41.
Chabahar Bay in SE of Iran is a shallow semi-enclosed environment affected by anthropogenic activities. In this paper, 19 sediment samples were collected and concentration of selected metals (Cu, Pb, Zn, Cd, Ni, Cr, Co, V and Fe) was determined using ICP-MS analytical method. Sediment samples from five stations were also selected for sequential extraction analysis and concentration of metals in each fraction was determined using ICP-OES. In order to investigate the environmental quality of Chabahar Bay, geographic information system (GIS) along with geochemical data, environmental indices and statistical analyses were used. Calculated contamination degree (Cd) revealed that most contaminated stations (Ch3, S1 and S3) are located SE of Chabahar Bay and contamination decreases in a NW direction. The S9 station, west of the bay, is also contaminated. High organic matter (OM) content in the sediments is most likely the result of fuel and sewage discharge from fishing vessels along with discharge of fishing leftovers. Significant correlation coefficient among OM, Fe, Cu, Pb, Zn and Cd seemingly reflects the importance of the role that OM and Fe oxy-hydroxides play in the metals mobility. The results of hierarchical cluster analysis (HCA), computed correlation coefficient and sequential extraction analysis suggest that Cu, Pb, Zn and Cd probably come from antifouling and sea vessel paints, while Ni, Cr, Co, V and Fe are most likely contributed by ophiolitic formations located north of the bay and/or deep sea sediments. Average individual contamination factors (ICFs) indicated that the highest health hazard from the bay is posed by Cu, Pb and Zn.  相似文献   
42.
《Comptes Rendus Geoscience》2015,347(3):134-144
The IASI mission flying onboard the MetOp satellites has been providing global observations of the air composition twice a day since 2007. From the atmospheric spectra recorded by the instruments in the thermal infrared spectral range, concentrations of a series of trace gases can be monitored, enhanced levels of pollution can be detected, and particle types can be determined to some extent. This paper recalls the historical context for the IASI remote sensor, reviews its capability to observe some key species for global and regional pollution monitoring, and reports on information services that benefit from the mission.  相似文献   
43.
本文将Fuzzy综合评判方法应用于建设项目的大气环境影响评价,并通过与其它评价方法的比较,说明Fuzzy综合评判方法在建设项目大气环境影响评价中的可行性和客观性。  相似文献   
44.
The proximity of the Great Barrier Reef (GBR) Marine Park to areas of intensive agriculture and increasing urbanisation places the park under potential threat of contamination by land-based pollutants. Passive samplers were deployed at inshore reef and river mouth sites in the Wet Tropics region of the GBR during a dry and a wet season to measure levels of land-based organic pollutants in this environment. Two types of passive sampling devices were deployed: (i) a polar sampler, which can be used to monitor polar herbicides and (ii) semipermeable membrane devices (SPMDs) which sequester more hydrophobic compounds (e.g. PAHs, chlorpyrifos). Herbicides (diuron, simazine, atrazine, hexazinone and/or flumeturon) were detected at low concentrations (ng L−1) at all sites sampled and in both seasons. Chlorpyrifos was not detected while PAHs were present in SPMDs at levels below limits of detection. The results show that the GBR environment does contain low levels of organic pollutants and that passive sampling provides a sensitive monitoring tool for measuring waterborne organic pollutants.  相似文献   
45.
This paper shows the results of a ground magnetic survey carried out to study solid waste landfills. The area located southward of Gualeguaychú town was chosen as a pilot case. This zone was selected considering the available knowledge about the cessation of operations, and the interest of the local authorities in verifying the existence of anomalies indicative of possible dangerous pollutants. The total magnetic field was measured along six profiles, and the corresponding anomalies were calculated. The profiles were modelled in 2.5 D, and along them Eulers deconvolution was used to estimate the depth to the sources. The first and the second derivatives of the residual magnetic field were calculated, in order to sharpen the anomalies. Our interpretation suggests that the characteristics of the modelled bodies and the magnitudes of the detected anomalies do not indicate the presence of drums in the sanitary infill.  相似文献   
46.
A number of specific factors must be considered when dealing with groundwater in urban areas. Urbanization significantly affects the natural water cycle, both in terms of quantity and quality. In particular, the main contributors to recharge and discharge clearly differ from those in natural systems. Moreover, water can affect underground structures and infrastructure characteristics of cities such as basements, public transport services (trains, underground railways, etc.), and utility conduits. As a result, urban groundwater is emerging as a distinct branch of hydrogeology. The objective of this paper is to review some of the topics that are specific to urban groundwater. These include (1) fluctuations in groundwater levels caused by changes in land and water uses; (2) pollution problems caused by point or non-point sources in urban areas; (3) characterization and quantification of the components contributing to groundwater recharge and discharge; (4) specific characteristics of groundwater flow and solute transport models in urban areas; and (5) integration of data for sustainable urban water management. Some of these issues are illustrated for the particular case of Barcelona, where a comprehensive hydrogeological study has been carried out during the last few years by both the public and the private sectors.
Resumen Se debe considerar una serie de factores específicos al tratar las aguas subterráneas en áreas urbanas. El proceso de urbanización afecta el ciclo natural del agua de manera significativa tanto en lo que se refiere a cantidad como a calidad. En particular, los contribuyentes principales a la recarga y descarga claramente difieren de aquellos aplicables a los sistemas naturales. Es más, el agua puede afectar los estructuras subterráneas de las ciudades tales como sótanos, servicios de transporte público (trenes, trenes subterráneos) y los servicios básicos. Como resultado de esto, la hidrogeologia urbana está emergiendo como una rama específica de la hidrogeología. El objectivo de este artículo es revisar algunos de los temas que son específicos al agua subterránea urbana. Estos incluyen: 1) Fluctuaciones en los niveles de agua subterránea causados por cambios en los usos de terreno y del agua; 2) Problemas de contaminación causados por fuentes puntuales o no puntuales en áreas urbanas; 3) Caracterización y cuantificación de los componentes que contribuyen a la recarga y descarga de agua subterránea; 4) Características especificas de flujo de agua subterránea y modelos de transporte de solutos en áreas urbanas; y 5) Integración de datos para el manejo sostenible de agua urbana. Algunos de estos puntos se han ilustrados para el caso particular de Barcelona en donde se ha llevado a cabo un estudio hidrogeológico amplio durante los últimos años tanto por el sector privado como el público.

Résumé Une série de facteurs spécifiques doit être considérée lorsque leau souterraine en région urbaine est étudiée. Lurbanisation affecte significativement le cycle naturel de leau, autant du point de vue quantitatif que qualitatif. Plus particulièrement, les zones de recharge et de décharge diffèrent considérablement des systèmes naturels. Leau souterraine peut affecter les structures souterraines ainsi que les infrastructures municipales telles que les sous-sols, les systèmes de transport publique (trains, métros, ...) et les conduits de service. De ce fait, lhydrogéologie en milieu urbain émerge comme une branche distincte de lhydrogéologie classique. Lobjectif de cet article est de revoir certaines notions qui sont spécifiques à létude de leau souterraine en milieu urbain. Parmi ces notions : 1) les fluctuations de la nappe phréatique causées par des changements dans lutilisation du territoire et de leau, 2) les problèmes de pollution causés par des sources ponctuelles ou diffuses en milieu urbain, 3) la caractérisation et quantification des composants qui contribuent à la recharge et décharge des aquifères, 4) les caractéristiques spécifiques des modèles découlement de leau souterraine et de transport de solutés en milieux urbain, et 5) lintégration des données pour la gestion durable de leau en milieu urbain. Certaines de ces questions sont étudiées pour le cas particulier de la ville de Barcelone où une étude hydrogéologique complète a été menée au cours des dernières années par les secteurs privé et public.
  相似文献   
47.
48.
Karabash (52°2 N, 60°10 E) is a copper smelting town in the southern Ural Mountains of Russia. The town is affected by sulphur dioxide emissions and deposition of metal-rich particulates from the smelter, acid drainage from old mine workings, and leachates from disused waste dumps and tailings dams. The close proximity of houses to these sources of pollution is of concern to human health and has devastated terrestrial vegetation in the environs. The environmental impact of the smelter on lakes in the area has been assessed using chironomids. Short sediment cores were taken from 16 lakes within a 50 km radius of the smelter and the composition of the chironomid fauna from the bottom of each core, representing conditions prior to the commissioning of the smelter in 1910, was compared with the present chironomid fauna in the surface sediments. Redundancy analysis (RDA) showed that changes in the chironomid fauna of most lakes were driven by trophic change, independent of the industrial activity. Lakes and ponds adjacent to the smelter and waste dumps, which directly receive contaminated waters were devoid of macro- and mesofauna and flora, but there is no evidence that other lakes have been severely impacted by smelter emissions. Local geology ensures that the lakes are well-buffered to the effects of acid deposition which will limit the bioavailability of metals in the water column and sediment.  相似文献   
49.
The article presents the results of lithological and geochemical investigations of recent sediments of Lake Pusty Staw. The analysed sediments document about 300 years of the history of this lake. Historical materials indicate that significant changes in the catchment of the lake took place from the beginning of the 18th century (deforestation and afforestation) followed by 19th century tourist development, and 20th century industrialisation. The sediments were dated using the 210Pb and 137Cs method and core lithology. These made it possible to establish a reliable chronology to the year 1730. The calculated sedimentation rates ranged between 0.17 and 0.83 cm year–1. There was a period of intensified erosion caused by land clearance between 1734 and 1810, which resulted in an acceleration in sedimentation rate (0.36 cm year–1) and a change of lithological type of sediment from detritus gyttja to clayey gyttja. On the basis of Cu, Zn, Cd and Pb content in the sediments, it was determined that the beginning of pollution of the lake dates back to the 19th century and was caused probably by the existence of a health resort. A systematic increase in pollution occurred in the 20th century as a result of industrial plants. Normalised with respect to Al, the content of heavy metals in polluted sediments was from several to twenty times higher than in sediments of the preindustrial period, and a comparison of historical materials with changes of sediments in most cases made it possible to identify the direct causes of the increase in pollution.  相似文献   
50.
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