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1.
This study draws attention to the fact that natural processes can mobilize thallium (Tl), a highly toxic metal, which may enter the food chain with severe health impacts on the local human population. A rural area having independent Tl mineralization in s…  相似文献   

2.
In the “Sea Diamond” shipwreck, it is estimated that almost 1.7 tons of batteries/accumulators and approximately 150 cathode ray tube technology televisions have gone to the bottom of the sea. Under these circumstances, all the aforementioned materials will eventually undergo severe accelerated corrosion. Consequently, a variety of heavy metals will either be released in seawater or precipitate in the form of salts resulting in contamination of the sea sediments. According to the ship data, and the aforementioned quantities of batteries and televisions, it is estimated that approximately 75–80 g of mercury, 630–1,050 g of cadmium and 1.14–1.26 tons of lead exist in the wreck only due to the electrical and electronic equipment present in the ship, not to mention the significant amount of heavy metals such as copper, nickel, ferrous and chromium that exist in the hulk. Four series of seawater sampling (n = 85) were conducted in different stations surrounding the wreck area in order to assess the overall impact from the release of heavy metals in the surrounding aquatic environment. The analysis indicated that there were stations where lead, zinc and cadmium were present in concentrations higher than the permissible limits set by the Unites States Environmental Protection Agency for seawater. Furthermore, the analysis of three series of sediment sampling (n = 31) from the wreck area showed elevated but expected concentration values for ferrous and manganese, considering the geological background of the area and contamination with lead, copper and cadmium.  相似文献   

3.
Three dumping sites have been formed at the northern region of Fushun City, Liaoning Province, for a large number of gangues including much oil shale that had been piled onto ground as gangue during long-term coal exploitation at West Fushun Open-pit Mine. Under appropriate conditions, self-combustion occurs after long-term exposure of oil shale and consequently such phenomena could be found almost everywhere at the three dumping sites. Much polycyclic aromatic hydrocarbons (PAHs) must be generated through oil shale self-combustion, a kind of incomplete combustion. In this paper, in order to make clear the PAHs distribution in oil shale and its self-combustion and their potential effects on surrounding environment, coal, low-grade oil shale, high-grade oil shale, burning oil shale, burnt oil shale and shaly soil collected from West Fushun Open-Pit Mine and West Dumping Site were analyzed quantitatively in 16 US EPA priority PAHs for the first time. Results showed that 16 PAHs in all samples were less than those in some bitumites and carbonaceous coals and were as much as those in lignites and anthracites from some Chinese mining areas. Coal and low-grade oil shale were abundant in lower molecular-weighted PAHs in contrast to high-grade oil shale with rich higher molecular-weighted PAHs. They had more benzo[a] pyrene than the highest background value in soils in Liaoning Province. So PAHs in these crude oil shales could cause potential effects on environment. There were at least 5121.40 p.g/kg PAils generated and at least 3976.70 μg/kg PAHs released into environment in the period from combustion beginning to sampling on the basis of calculation. Furthermore, the concentrations of 3-4 ring PAHs among them were very high. Therefore it could be said that oil shale self-combustion aggravated the environmental impacts of PAHs in oil shale. The low concentrations of PAHs in shaly soil showed that much PAHs had been released through recultivation and biodegradation.  相似文献   

4.
Coal is an important natural resource in Botswana. The best coals so far found occur in the Morupule coalfield, west of Palapye, where nearly 8000 million tons have been identified (Carney et al., 1994). In this study we investigate the environmental impact of the mining and consumption of the high-ash, medium-calorific value bituminous coal in the eastern part of Botswana, which may serve as a reference for other coal mines and coal-based power stations around the globe. More than two hundred surface soil samples and three profile soil samples were collected around Morupule Colliery, Morupule Power Station and Palapye.  相似文献   

5.
Ecotourism environmental impact assessment is a traveling activity relevant influence prediction and appraisal. And the setting-up of the index system is very important to implement the appraisal of environmental impact of ecological travel. According to …  相似文献   

6.
We describe contemporaneous changes in environmental quality and social deprivation in English local authority districts over four decades, using secondary source GIS modelled data on environmentally intrusive development. The distribution of this development is described with respect to the Townsend material deprivation score, corroborated against the Breadline Britain index. Spatial patterns of environmental intrusion and material deprivation change markedly over the period, although a clear environmental inequality remains throughout. However, it is not the most deprived who experience the greatest decline in their environmental quality, as most of the increase in environmental intrusion occurs in those districts whose population were amongst the most affluent in the early 1960s. We note that the environmental justice implications of these observations are dependent upon conceptions of justice held, and reflect on the challenge of testing, through empirical longitudinal analysis, the notion that environmental sustainability and social justice are incompatible.  相似文献   

7.
The bentonite deposit of Lahij Province, Yemen, has very promising commercial applications due to its mineralogy and physical and chemical properties. It was examined to determine its mineralogical composition, chemical and physical properties of the bentonite deposit, purity and sodium-exchanged bentonite. Modified bentonite was synthesized by exchanging cetyltrimethylammonium cations for inorganic ions on the bentonite and its adsorption properties for ammonium were characterized in batch experiments. Analytical methods were carried out to study the bentonite comprising X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy, chemical analysis and kinetic and isotherm models were also tested. The results have shown that the purification of bentonite resulted in a bentonite fractions of the total sample composed of montmorillonite and <5 % quartz. The XRD data showed that the interlayer spacing (d 001) of bentonite decreased from 15.3 to 12.5 Å and then increased to 19.7 Å. Moreover, high cation exchange capacity, good water absorption and high swelling capacity were also obtained. The results have shown that the modified bentonite was more effective than the natural bentonite for ammonium removal. In addition to that, pseudo-second-order kinetic model, Freundlich and the Langmuir models described the adsorption kinetics and isotherm well. It was concluded that Yemen (Alaslef) bentonite can be potential adsorbents for ammonium removal.  相似文献   

8.
Groundwater of Egypt: “an environmental overview”   总被引:1,自引:0,他引:1  
Although Egypt has the great Nile River, which is the main supply of water, Egypt’s water is limited to 55.5 billion m3 per annum. Owing to the rapid growth of the population and the increasing consumption of water in agriculture, industry, domestic use, etc., it is expected that Egypt will rely to some extent on groundwater to develop the new projects such as Tushka in Upper Egypt and East Oweinat. Issues related to groundwater in Egypt are identified with the common geological features associated with formation of the aquifers and demonstrating the location of the main resources of groundwater, followed by the main objective of this paper, which is addressing the environmental issues related to groundwater in Egypt. Several studies have been reviewed and personal communication made with the authorities to introduce this work and provide an overview of the groundwater quality problems in Egypt with examples from different parts of the country.  相似文献   

9.
The May–August 2005 heavy rainstorm events in Romania triggered a large number of geomorphic hazards of great magnitude, consisting of primarily floods and landslides. Some of the most affected regions were the Curvature Carpathians and Subcarpathians. This paper addresses the effects of rainfall on slopes, especially in the middle sector of the Sibiciu basin (the Buzău Carpathians) outlining the significant landslide damage along the road connecting the Colţi and Aluniş villages. The landslides are analyzed in terms of geologic, geomorphic and engineering geologic features, focusing on the Colţi–Aluniş landslide which had the greatest impact on the road displacement. The related environmental and social impacts are also discussed.  相似文献   

10.
In early summer 2005, acidic, metal-laden water and clay-rich debris flooded down the flanks of the Chiginagak Volcano, Alaska. The estimated 3-million-m^3 discharge occurred during a rapid partial draining of a newly formed summit crater lake. Twenty-seven kilometers downstream from the source, Mother Goose Lake, a 500-million-m3 lake, was acidified from surface to bottom (pH ranged from 2.9 to 3.06). All aquatic life was killed and salmon spawning runs were eliminated. The flood was accompanied by a simultaneous release of caustic volcanic gas and aerosols that followed the flood flow-path, and caused defoliation and necrotic leaf damage to vegetation in a 30-km^2 area along and above affected streams. In September 2005, approximately 1.4 million m^3 of acidic water remained and continued to drain from the summit crater lake. Water sampled 8 km downstream after considerable dilution from glacial meltwater was a weak sulfuric acid solution (pH-3, SO4^2- ~500 mg/L, and SO4^2-/Cl~10). Cation proportions decreased in the order of Ca〉Fe〉Al〉Mg〉Na〉K. The eightfold predominance of Ca^2+ over Mg^2+ may reflect some dissolution of anhydrite, but only about 30% of the SO4^2- can be balanced by Ca^2+. The anomalously high concentrations of Fe (-25 mg/L) and A1 (-18 mg/L) are derived from rock dissolution under the acidic conditions within the crater lake, and appear to be the most serious environmental threat in terms of metals. Further downstream, at stream and lake sites ranging from 8 to 40 km from the source, concentrations of cations remained high and hazardous metals such as As, Cr, and Cu were elevated well above background levels. Copper concentrations exceeded the U.S. Environmental Protection Agency's chronic exposure limit for aquatic life at most sampled sites and several sites exceeded the acute exposure limit.  相似文献   

11.
As demand for energy is growing and resources become scarcer, energy increasingly becomes the site of heated controversies. In Latour’s terms, energy turns from a “matter of fact” into a “matter of concern”. In these energy controversies, environmental movements frequently play a central role, highlighting what is at stake in these developments. While these movements have often been studied, these studies rarely focus on the interaction between controversies, environmental movements, and place-making. In this article, we not only argue that energy is frequently turned from matter of fact into a matter of concern, but that this argument also extends to the notion of place. As such, energy controversies turn villages, cities, or regions themselves into “places of concern”. The article delves deeper into the production of places of concern through two case studies of energy controversies around power plants: a proposed coal plant in Bo Nok, Thailand, and HidroAysen, a hydropower project in Chilean Patagonia. We specifically focus on the issues that were opened up for debate in both countries, and on the role of environmental movements in the production of these places. Our examples are based on fieldwork and interviews in these two areas, as well as media and document analysis. While the two cases are from two different countries, we nonetheless find surprising parallels between them. These insights are instrumental to link theoretical debates on controversies and place-making. Moreover, they provide empirical insights into the transformative and lasting effects of energy controversies on people and places.  相似文献   

12.
In the history, the Yellow River nurtured Chinese civilization. It is respected as the "ancestor of the four large rivers in China" and praised as "the mother river of China". At the same time, the Yellow River is regarded as "the misery of China" and considered as the most complex river hard to control in the world. Today, the Yellow River is also one large river greatly influenced by human activities in the world. The safety of the Yellow River, particularly flood control, is always the most important issue for governing and developing the country. Great achievements have been made after many years of efforts for controlling the Yellow River. However, since the nineties of 20 century, some new problems occurred, such as sharp reduction of flux to sea, dry rivercourse, worsen environment, etc. Rapidly shrinking riverbed and two-level perched stream are disadvantageous to flood safety especially. The new concepts and new practices are urgently needed to control the river. Therefore, the Yellow River Conservancy Committee of Ministry of Water Resources had continuously carded out flow and sediment diversion each year from 2002 to 2005. To timely probe into the new issues produced after flow and sediment diversion, and in order to deepen the understanding of rules for the Yellow River's water and sediment and provide reference and experience to the researchers for other large rivers, five hydrologic and hydraulic characteristics of the Yellow River, such as lack of water, much of sediment, different resources of water and sediment, inconsistency between water and sediment and frequency of sink switching and route changing, are described. Flow and sediment diversion of the Yellow River is also reviewed. Under flow and sediment diversion,  相似文献   

13.
Holocene sedimentation patterns and environmental development in Aarhus Bay, Denmark, were reconstructed based on proxy analyses of two sediment cores (M1 and M5). Together, the two cores offer an opportunity to examine the history of the area during the past c. 10 000 years. The investigation consisted of acoustic mapping and multi-proxy analyses of the sediment cores including macrofossils, sediment physical properties, sediment accumulation rates, grain size, and X-ray fluorescence elemental counts. Radiocarbon dating of the two sediment successions revealed that they cover the periods c. 10 000–3700 cal. a BP (M1) and c. 4400 cal. a BP to the present (M5). The data from the M1 site indicate the presence of a near-shore lake environment between c. 10 000 and 9000 cal. a BP. The first intrusion of marine water into the area is dated to c. 9000 cal. a BP. In the following c. 1300 years, brackish-water conditions prevailed in the area characterized by a mixture of taxa from marine, limnic and terrestrial habitats, reflecting a shallow estuarine environment. Around 7700 cal. a BP full marine conditions were established, accompanied by a marked increase in sedimentation rates. The changes to full marine conditions and higher sedimentation rates are probably due to a significant sea-level rise leading to flooding of former land areas and intensified erosion. A subsequent distinct decrease in sedimentation rates around 6350 cal. a BP is presumably linked to a previously documented sea-level drop about this time. Continuous sedimentation ceased around 3700 cal. a BP in the central part of the bay, most probably due to a major sea-level lowering involving widespread erosion. In the eastern and deeper part of the bay, sedimentation continued until today. Fully marine conditions prevailed there for at least the last 4400 years.  相似文献   

14.
Through elementary geophysical prospecting, chemical exploration and geological exploration, there are above 100000 t Mo reserves in Wenquan Wushan, Northwest China. Presently, the molybdenum mine has gone deploitation and construction. Data from drillings indicated many associated elements such as Cu, Pb, Zn, etc. with Mo. Through complete water quality analysis, we found water here comes up to drinking-water standard. This paper investigated the environmental geochemistry characteristics and evaluated water quality in mine field under existing conditions, which may present reference for forecasting the trends of environmental pollution change, underwater environmental monitoring and protection after exploitation. In exploitation of mineral areas, the surroundings of ore areas and groundwater environmental quality are affected correspondingly. The paper analyzed benefication process and tailing disposal process, and consequently, predicted pollution sources, pollution pathway and post-effect that may come along. Also, the interactions between water and rocks with human activity are discussed.  相似文献   

15.
Hydrochemical analysis results suggest four different water types: bicarbonate dominant water (facies-I), sulfate dominant cold brine water (facies-II), sodium-bicarbonate dominant thermal water and thermal and mineralized water (facies-III), and sulfate–chloride dominant thermal and mineralized water (facies-IV). The mineral content/salinity of the water is related to the ions that these waters dissolve from the minerals on the rocks during infiltration and circulation in the saturated zone. Gypsum cover units that exist on the granitoids in the region is the main factor for the ion increase in the facies III geothermal water similar to the cold brine water (facies II). Isotopic analyses indicate that the thermal springs (Dutlu bath spring, Aya? bath well, Çoban bath well and Kapullu bath spring) are of meteoric origin and receive recharge from precipitation in the Beypazar? granitoids and around gypseous formations with elevations of about 950–1,150 m. Karakaya bath well and Il?ca bath spring thermal water points are recharged from the Bilecik limestone hills, Tekke volcanics and ?ncedoruk Formations. Karakoca mineral spring of thermal and mineralized water is recharged from out of the study area. According to oxygen-18 (SO42?) and sulfur-34 (SO42?) contents, sulfate in water samples from Aya? and Dutlu resorts as well as Çoban bath is derived from the gypsum of Kirmir Formation as the primary source. Sulfates of the Kapullu bath water and Karakoca mineral water originate from secondary sources such as pyrite oxidation and bacteriological reduction.  相似文献   

16.
River restoration through dam removal provides an opportunity to investigate the changing nature of environmental conflicts and politics in long-humanized landscapes. In New England, where over 14,000 dams fragment the region’s rivers, dam removals are often highly contested. This is due, in part, to how the intertwined roles of history, identity, and aesthetics coalesce to create attachment to place and inspire the defense of dammed landscapes. Dam removal provides a useful lens to consider the following: How do the historical and geographical contingencies of this region shape and alter conflicts over dam removal in specific ways? In instances where conflicts emerge, what do the conflicts reveal about the politics of ecological restoration in highly altered landscapes? We use a political ecology approach to reveal how complex cultural dynamics, competing interpretations of science and the environment, micropolitics, and the role of multiple actors generate and shape conflicts over dam removal. We show that the historical geography of New England influence conflicts over removal in important ways, particularly with regard to the roles of aesthetics and identity in landscapes that are characterized largely by consumptive as opposed to productive uses. Our findings also suggest that restoration in long-humanized landscapes will embroil new constellations of human and nonhuman actors, requiring attention to the political and cultural, as well as the ecological, dimensions of restoration. This paper contributes to research on the political and social dimensions of dam removal, as well as to research at the nexus of ecological restoration and environmental politics.  相似文献   

17.
Fine atmospheric dust includes mineral particles and aggregates, fibrous minerals and fibrous organic material. Generation, dislodgement and transport (deflation) of natural dust with the finer (〈4 microns) components suspended as silt-size aggregates, is widespread in and adjacent to the world's drylands, as well as deriving from volcanic vents. Silica is a highly fibrogenic agent in lung tissue. Long-term inhaling of siliceous dusts can lead to a number of fibrotic lung diseases, including natural (non-occupational) pneumoconioses (notably silicosis, but including asbestosis and others). Different polymorphs of silica show different levels of toxicity in interaction with lung tissue. Particles with highly active surfaces may release radicals, causing cell damage. Some types of inhaled particulates are degraded by macrophages, but many are highly resistant and persist in the lungs, some stimulating fibroblastic cells to deposit collagen. Silicosis is an inflammation of the lung commonly caused by silicate mineral particles, leading to fibrosis. Three types are recognized: nodular pulmonary fibrosis (simple or chronic silicosis), acute silicosis, and accelerated silicosis. Generally, finer particulates have greater oxidative capacity than the coarser fractions. They contain more reactive oxygen species, their greater bioreactivity making them more toxic to pulmonary tissue. Nevertheless, inhalation of large dust particles (〉 10μm) may constitute a health risk if the mineralogy is toxic, regardless of where the grains lodge in the respiratory system. Dust may absorb harmful gases, disease-generating bacteria and carcinogenic hydrocarbon compounds. Silica-related respiratory disease may also an exacerbate cardiac problem, and epidemiology suggests a link with tuberculosis. Quantification of dust loading and exposure requires study of spatial and temporal patterns, supported by meteorological analysis, airflow modeling and satellite-borne imagery. Some acute, short-term health impacts have been assessed using atmospheric and health records both before and after a dust storm or by comparison of populations within and outside such events. Analysis of the size, shape, mineralogy and geochemistry of ambient dust particulates provides information on natural dust sources, dust concentrations, and potential particulate toxicity, as well as providing a datum for assessment of human exposure levels.  相似文献   

18.
Zn and Pb smelters are the major contributors to Zn and Pb emissions among all anthropogenic sources, thus, it is essential to understand Zn isotopic variations within the context of metallurgical industries, as well as its fractionation in different environments impacted by smelting activities. This mini review outlines the current state of knowledge on Zn isotopic fractionation during the high-temperature roasting process in Zn and Pb refineries; δ66Zn values variations in air emissions, slags and effluents from the smelters in comparison to the geogenic Zn isotopic signature of ores formation and weathering. In order to assess the environmental impact of these smelters, the available and measured δ66Zn values are compiled for smelter impacted natural water bodies (groundwater, stream and river water), sediments (lake and reservoir) and soils (peat bog soil, inland soil). Finally, the discussion is extended to the fractionation induced during numerous physicochemical reactions and transformations, i.e. adsorption, precipitation as well as both inorganic and organic surface complexation.  相似文献   

19.
The Eastern Desert of Egypt represents a remote arid area which is scarce in water resources. The area is characterized by many mining sites to exploit the phosphate deposits; thus, these activities can generate groundwater contaminants. The main objective of the present study is discussing the effect of the mining activities and phosphate bearing rocks on groundwater. The obtained results pointed out that the water bearing formations can be distinguished as Quaternary alluvial, Oligocene sandstone, Campanian phosphate limestone (Duwi Formation), and Precambrian basement rocks. Some of the investigated groundwater shows relatively high concentrations of trace elements compared to other samples, such as Pb, Zn, Cu, Cr, Ni, and Sr. This is consistent with the analyses of phosphate rocks which are also enriched in the same trace elements. The high groundwater salinity is due to evaporation, limited re-charge, and leaching of salts in rocks. The results of speciation modeling reveal that majority of groundwater samples are supersaturated with calcite, aragonite, and dolomite, and some samples are also at equilibrium or supersaturated with hydroxyapatite. The groundwater quality in the study area evaluated for human drinking, livestock and poultry domestic, and industrial purposes is not suitable in most wells. It is obvious that the groundwater contamination occurs when drilling wells penetrate the phosphate bearing beds and not only at mining activity sites. Therefore, it is recommended to avoid any groundwater exploration from the Duwi Formation and also select the drilling sites outside the mining areas.  相似文献   

20.
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