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1.
Egypt is located in the Northeast of Africa where oil and gas (O&G) are produced offshore from the Gulf of Suez and the Southeast part of the Mediterranean. The O&G production in Egypt is distributed as follows: 70% from Gulf of Suez, 16% from Western desert, 8% from the Sinai Peninsula and 6% from Eastern desert. Past O&G activities, refining and transport have resulted in chronic pollution in Egyptian offshore and numerous environmental programs have been initiated to protect new development areas from the environmental impacts. The offshore drilling process uses drilling fluids (mud) and generates waste fluids and cuttings, which could be the largest discharges going into the receiving water bodies. There are several options to manage offshore drilling wastes: offshore discharge, offshore down-hole injection and onshore disposal. Water-based drilling fluids (WBF) are commonly employed for drilling in Egyptian offshore because of their expected environmental benign behavior. The main objective of this paper is to develop a methodology to determine the fate of heavy metals associated with WBF drilling waste in the marine environment and estimate the associated ecological risks. Proposed contaminant fate model is based on an aquivalence approach, which has been integrated with fuzzy-based analysis to study the uncertainties. This research concluded that the impacts of heavy metals associated with the drilling waste discharges in the receiving waters are minimal.  相似文献   

2.
Membrane-filtration or dialysis techniques are increasingly used for the partial desalting of waters, e.g. brackish waters. By the use of Bulgarian PAN and acetate-cellulose separating membranes there are eliminated also organic substances – inclusive of humic matter – from natural waters to different degrees. The experimental arrangement is described and the measured results for COD-Mn, concentrations of humic acid and specific electrolytic conductivity are summarized in tables. The humic acid concentration (2.8 mg/l) was reduced by about 79 % by ultrafiltration, 82 % by reverse osmosis and 62 % by electrodialysis. The efficiency of the investigated techniques could be increased under certain conditions.  相似文献   

3.
After the Marmara (Izmit) Earthquake (magnitude 7.4) on 17 August 1999, chemical oceanographical characteristics of Izmit Bay were investigated in order to examine the possible effects of the refinery fire and uncontrolled entrance of domestic wastes to the surface waters. The dissolved oxygen (DO) content of the water column in August 1999 was the lowest value of all the measurement periods. It was found to be lower than the detection limit of the method (0.03 mgl(-1)) in the lower layer of eastern and central basins of the Bay, whereas the dissolved hydrogen sulfide (DHS) values were high, varying between 0.14 and 1.28 mgl(-1). The deficiency of DO and in turn formation of DHS were caused by the spreading petroleum from the refinery fire onto the sea surface and waste loads from the damaged municipal waste effluent system. The increasing organic/inorganic loads into the Bay stimulated the phytoplankton blooms which cause locally saturated DO concentrations in the eastern basin during autumn 1999. DO concentrations increased in lower layer waters during winter, whilst DHS formation disappeared when water originating from the Marmara Sea replenish the water column of Izmit Bay. However, DHS formation established again in August 2000.  相似文献   

4.
The successful purification of waste waters from the leather and textile industries is possible by flocculation with aluminium sulphate and alkaline-earth chlorides. BaCl2 proved very successful among the applied alkaline-earth chlorides. The removal of oily emulsions and tensides was very effective when the waste waters were treated by a two-stage flocculation process. By an excessive application of BaCl2 also a reduction of sulphate was obtained. Wastewaters treated in the neutral range showed a purification effect of 98 %, so that the effluents were clear and colourless. The time of sedimentation amounted to 1 h only. Segregated oil was successfully removed with the aid of a very absorptive polyurethane foam.  相似文献   

5.
Measurements of magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) on both filtered particulates and sediment samples provide a cheap, rapid and non-destructive method of particulate pollution monitoring in marine environments where ferrimagnetic iron oxides are important components of the discharge from industrial or urban complexes. The value of this approach is illustrated by reference to results obtained from the Elefsis Gulf, Greece, where the major source of particulate metal pollution is an iron and steel works discharging waste into a settling lagoon connected to the waters of the Gulf.  相似文献   

6.
Moiseenko  T. I. 《Water Resources》2002,29(3):292-298
A method for determining the critical loads of acid fallout for surface waters is described. Adaptation of the method for estimating the degree of water acidification in the Kola North is demonstrated in the process of large-scale investigations carried out in this region. The limiting value of the acid-neutralizing capacity of waters needed for preventing the aquatic ecosystems from degradation is substantiated. The loads of acid fallout in 17% of 460 examined water systems are found to exceed the critical limits and create the conditions for further development of adverse processes in water systems.  相似文献   

7.
The contamination and resulting degradation of water coursesby effluents from abandoned and active mines is a world-wideproblem. Traditional methods of remediating the dischargesfrom mines involve the addition of chemicals and the utilisationof artificial energy sources. Over the last 15–20 years passivetreatment systems have been developed that harness naturalchemical and biological processes to ameliorate the potentiallytoxic effects of such discharges. There are many different typesof passive system, including compost wetlands, reducing andalkalinity producing systems (RAPS), permeable reactive barriersand inorganic media passive systems. Different waste materialscan be utilised as reactive media within each of these systems,dependent upon the type of mine water and treatment technology.In many cases the reactivity of these recycled waste materialsis key to the remedial performance of these systems. The materialsused may be organic (e.g., composts) or inorganic (e.g., blast furnaceslag) and where possible are sourced locally in order to minimisetransport costs. The remediation of mine waters in itself canproduce large quantities of waste products in the form of ironoxide sludge. Potential uses of this material in the productionof pigments and in the treatment of phosphate contaminatedwaters is also currently under investigation.The exploitation of what are traditionallythought of as waste materials within treatmentsystems for polluted waters is an expandingtechnology which provides great scope for recycling.  相似文献   

8.
Surface mining in the Elk Valley, British Columbia, involves removing vegetation, soil, and rock to access underlying metallurgical coal. Subsequent waste rock is placed into adjacent valleys, frequently burying headwater streams. Due to their coarse texture, waste rock piles increase infiltration and percolation, increasing solute transport and concentration of geochemicals in downstream surface waters. Previous research suggests that weathering solutes are transport limited, and it is hypothesized that revegetation will enhance evapotranspiration (ET) and reduce percolation through the waste rock, potentially reducing loading. This study examined the surface‐atmosphere water and energy exchanges using the eddy covariance technique for three waste rock surfaces with different levels of reclamation: (a) an ~25‐year‐old mixed coniferous forest, (b) a grass site, and (c) bare waste rock. Measurements were taken from May to October in 2013 and 2014. Soil moisture and matric suction were measured to 1‐m depth. Sap flow at the forested site was measured to partition transpiration from total ET. In all years, ET rates were greatest at the forested site, followed by the grass cover and lowest at the bare waste rock site. Growing season ET rates at the forest were 56% higher than grass in 2013 and 35% higher in 2014. At the vegetated sites, climate was the main driver of ET, with high radiation, and warm and dry conditions enhancing fluxes. Maximum ET at these sites corresponded with peak growing season, with vegetation increasing both transpiration and rainfall interception. At the bare rock site, ET was weakly related to atmospheric conditions, and ET rates briefly increased during periods following rainfall when near‐surface soil moisture was enhanced. Transpiration comprised 29% of overall ET at the forest site from late July to early October. Results suggest that vegetation establishment can be incorporated into mine reclamation plans to enhance ET rates and limit percolation, potentially reducing downstream geochemical loads.  相似文献   

9.
The increasing demands on recreational waters have made microbial contamination a matter of public and scientific concern. This study aimed to search for Salmonella spp. in waters classified according EU Directive 2006/7/EC, in order to assess associations between its prevalence and the concentration of the non-pathogenic new faecal indicators: Escherichia coli and intestinal enterococci. Although a statistically significant association was observed Salmonella was detected on beaches classified as “Good” (9.3%) and “Excellent” (14.4%) which compromises the idea that faecal indicators can be predictors of pathogens.Attending the high prevalence of Salmonella found (23.1%) it seemed important to improve the efficiency of the conventional analytical method (ISO 6340:1995), comparing its draft with SML-VIDAS Salmonella and two new chromogenic media: AES Salmonella Agar Plate (ASAP) and Simple Method Salmonella (SMS). ASAP showed the higher efficiency and can be recommended for a faster detection and presumptive identification of salmonellae in bathing waters.  相似文献   

10.
The fate of estrogenic activity in waste water effluent was examined during surface transport and incidental recharge along the Santa Cruz River in Pima County, Arizona. Based on measurement of boron isotopes, the fractional contribution of reclaimed water in surface waters and ground water wells proximate to the river was determined for a contemporary sample set. Estrogenic activity decreased by −60% over the 25 mi length of the river below effluent discharge points in Tucson. In ground water samples obtained from monitoring wells that are proximate to the Santa Cruz River, both dissolved organic carbon ( p = 0.0003) and estrogenic activity ( p = 3 × 10−6) were highly correlated to fractional waste water content. Results indicate that proximate ground water quality is sensitive to incidental recharge of reclaimed water in the Santa Cruz River bed. In a few locations, little attenuation of estrogenic activity was apparent during percolation of effluent in the river channel to well withdrawal points.  相似文献   

11.
Today already numerous micromycetes are a recognized part of the biocenosis of growth in receiving waters strongly polluted by organically rich waste waters and of growth on biofilter media surfaces. The principal representatives are some Deuteromycetes, Mucorales and Saccharomycetaceae, whereas the so-called true aquatic fungi (Oomycetes) with the exception of Leptomitus lacteus are practically absent. The growth of micromycetes in activated sludge remains still an unanswered question. Generally, the filaments in the activated sludge are ascribed to filamentous bacteria and as long as fungi were isolated from activated sludge their presence has been reported only in the form of spores. The nitrogen deficiency with regard to carbon present in the waste water is considered as one of the factors enhancing the development of fungi in the activated sludge. In a series of 13 tests carried out on laboratory-scale batch models using synthetic waste water, where the carbon source was glucose and the nitrogen source was (a) sodium nitrate, (b) ammonium sulphate, and (c) peptone, the fungal growth was studied in different models with the BOD:N ratio varying from 20 to 1000. The models were seeded with thickened activated sludge from the municipal sewage works. The sludge did not contain any microscopically detectable forms of fungoid growth. It was found that the fungi in activated-sludge medium grow well and both in the forms of single cells, occuring independently and in chains, as well as in the form of long branched filaments. In some instances, the micromycetes formed up to 80 to 100 per cent of the biocenosis of the activated-sludge flocs, but the dependency of their development on the increasing BOD:N ratios in the waste water has not been ascertained. Fifteen species of micromycetes were isolated and identified, and in addition several representatives of Saccharomycetaceae, which were not identified.  相似文献   

12.
Wicks C  Kelley C  Peterson E 《Ground water》2004,42(3):384-389
Adverse impacts on the health of some fish populations, such as skewed sex distributions, have been noted in surface waters and in laboratory experiments with relatively low concentrations (above 25 ng/L) of natural estrogen (17 beta-estradiol--E2). Sources of E2 to surface and ground waters can include avian, human, and mammalian waste products. The Ozark Plateau Aquifer (OPA) is a karstic basin that receives a significant portion of its water through losing reaches of rivers. Thus, there is a direct connection between surface water and ground water. The OPA was targeted for an E2 study to assess the potential for adverse health effects to aquatic organisms living in the system. Eight springs, which drain the aquifer, were sampled quarterly. The concentrations of E2 in the OPA ranged from 13 to 80 ng/L. For any one sampling event, the concentrations of E2 at the spring waters were statistically similar; however, the concentrations of E2 at all springs varied throughout the year. At Maramec Spring, one of the larger springs, the E2 concentration, was correlated with discharge. Based on the correlation between discharge and E2 concentration, aquatic organisms living in the plateau or in its discharged waters, including the threatened southern cavefish T. subterraneus, are exposed to concentration of E2 above 25 ng/L approximately 60% of the time. This implies that organisms living in karst basins throughout the OPA are likely exposed to E2 concentrations that may adversely impact their reproductive success for a significant portion of each year.  相似文献   

13.
After an outline of the possibilities and difficulties connected with the polarographic determination of aqueous quinone solutions, a specified oscillo-polarographic method of investigation is described. By the examples of solutions of pure substances as well as of the industrial waters of a pulp mill (up to 2.3 mg/1 total quinone) the conditions for applying the technique developed art' explained. The relative error of this method does not exceed 3%  相似文献   

14.
This survey evaluated the monthly accumulation rate of marine debris and the types of objects washed ashore at Volunteer Beach on East Falkland between October 2001 and March 2002. The mean (±SD) accumulation rate of marine debris was 77 ± 25 items/km/month, of a mean weight of 17.3 ± 12 kg. Forty different objects were collected and the five most frequent items were cotton fabric, string, polystyrene packing sheet, plastic packing tape and broken plastic pieces. The debris on Volunteer Beach was dominated by fishing debris; 42% of the items were discarded fishing equipment, while 39% of the items were of a packaging or associated nature. The mostly likely source of this household waste was fishing vessels, with Falkland Islands Government (FIG) fisheries observers seeing 27 of the 40 items of debris collected from Volunteer Beach being discarded from fishing vessels. It is suggested that, although further marine debris research is warranted, more effective at-sea ship waste disposal regulations are required in Falkland waters to reduce environmental and economic threats both at the local and international level.  相似文献   

15.
The aim of this study was to investigate the potential application of the beta-d-glucuronidase (GLUase) activity measurement for the routine detection and quantification of E. coli in marine bathing waters. GLUase activity was measured as the rate of hydrolysis of 4-methylumbelliferyl-beta-d-glucuronide. Culturable E. coli were quantified by the most probable number (MPN) microplate method. Both methods were applied to a large set of seawater samples. Significant correlation was found between the log of GLUase activity and the log of culturable E. coli. The mean coefficient of variation (CV) of the GLUase activity was less than 15% at concentrations around the current standards of International regulations whereas the CV of the microplate method was around 30%. When samples were stored at 4 degrees C and 20 degrees C, the mean CV of the GLUase activity remained below 15% up to 6 hours after sample collection whereas the range of variation of the microplate method varied between 10 and 50%. We concluded that the GLUase activity is an operational, reproducible, simple, very rapid and low cost method for the real-time enumeration of E. coli in bathing waters and should be preferred to the microplate method. The GLUase activity method should be routinely applied to the rapid enumeration of E. coli in recreational waters and recommendations for its application were suggested to water quality managers.  相似文献   

16.
Numerous pathogenic agents have been found in freshwaters used as sources for water supplies, recreational bathing and irrigation. These agents include bacterial pathogens, enteric viruses, several protozoans and parasitic worms more common to tropical waters. Although infected humans are a major source of pathogens, farm animals (cattle, sheep, pigs), animal pets (dogs, cats) and wildlife serve as significant reservoirs and should not be ignored. The range of infected individuals within a given warm-blooded animal group (humans included) may range from 1 to 25%. Survival times for pathogens in the water environment may range from a few days to as much as a year (Ascaris, Taenia eggs), with infective dose levels varying from one viable cell for several primary pathogenic agents to many thousands of cells for a given opportunistic pathogen. As pathogen detection in water is complex and not readily incorporated into routine monitoring, a surrogate is necessary. In general, indicators of faecal contamination provide a positive correlation with intestinal pathogen occurrences only when appropriate sample volumes are examined by sensitive methodology. Pathways by which pathogens reach susceptible water users include ingestion of contaminated water, body contact with polluted recreational waters and consumption of salad crops irrigated by polluted freshwaters. Major contributors to the spread of various water-borne pathogens are sewage, polluted surface waters and stormwater runoff. All of these contributions are intensified during periods of major floods. Several water-borne case histories are cited as examples of breakdowns in public health protection related to water supply, recreational waters and the consumption of contaminated salad crops. In the long term, water resource management must focus on pollution prevention from point sources of waste discharges and the spread of pathogens in watershed stormwater runoff.  相似文献   

17.
The environmental policies aimed at reducing nutrient emissions from the agricultural sectors in the Baltic states, Poland, Germany and Scandinavia are detailed. The emissions include leaching, run-off and erosion losses of nitrogen and phosphorus, volatile losses of ammonia, and farm waste discharges. Farm waste discharges and nitrate leaching from agricultural fields have received considerable attention during the last few decades, but more recently the remaining loss categories have also been recognized as substantial contributors of nutrients to the environment.

Environmental targets have been set in the Helsinki Commission (HELCOM) Ministerial Declaration of 15 February 1988, stating that a significant reduction (e.g. 50%) of the nutrient load to the Baltic Sea shall be reached before 1995. A similar target for the Oslo and Paris (OSPARCOM) Convention waters has been set by the North Sea ministers, while the EU Nitrate Directive expresses an environmental standard by setting an upper limit to nitrate concentrations in groundwater.

It is argued here that in most instances only marginal reductions in agricultural emissions will be achieved under the current policies before 1995 (or later). Exceptions are seen in transition economy countries where fertilizer consumption and livestock production have decreased significantly. As agriculture is a major source of nutrients to convention waters, the overall 50% reduction target will not be met. Furthermore, it is argued that there is scope for a considerable reduction of losses from agriculture and that the instruments to achieve the objectives are readily available. Measures should focus on the total input of nutrients to the agro-ecosystems and not so much attempt to regulate specific management practices. The more prominent instruments include the reduction or alteration of agricultural subsidies, market considerations and the use of environmental taxes (on fertilizers and nutrients in animal manure) combined with in-depth structural regulations. It is, however, necessary to generate further political willingness to ensure decisions and successful implementation of the various measures—a process which requires public attention.  相似文献   


18.
The Bohai Sea is a semi-enclosed inland sea with case-2 waters near the coast. A comprehensive set of optical data was collected during three cruises in June, August, and September 2005 in the Bohai Sea. The vertical profile measurements, such as chlorophyll concentration, water turbidity, downwelling irradiance, and diffuse attenuation coefficient, showed that the Bohai Sea was vertically stratified with a relative clear upper layer superimposed on a turbid lower layer. The upper layer was found to correspond to the euphotic zone and the deep chlorophyll maximum (DCM) occurs at the base of this layer. By tuning a semi-analytical model (24 and 25) for the Bohai Sea, we developed a method to derive water inherent optical properties and the depth of DCM from above-surface measurements. Assuming a ‘fake’ bottom in the stratified water, this new method retrieves the ‘fake’ bottom depth, which is highly correlated with the DCM depth. The average relative error between derived and measured values is 33.9% for phytoplankton absorption at 440 nm, 25.6% for colored detrital matter (detritus plus gelbstoff) absorption at 440 nm, and 24.2% for the DCM depth. This modified method can retrieve water inherent optical properties and monitor the depth of DCM in the Bohai Sea, and the method is also applicable to other stratified waters.  相似文献   

19.
This paper presents the status of summer oxygen conditions in estuarine and coastal waters around Ireland between 2003 and 2007. Of the 95 water bodies surveyed, 85 had oxygen levels sufficient to support aquatic life. This corresponds to a surface area of 3125 km2 or 99.4% of the total area assessed. Ten water bodies, representing a surface area of 20.2 km2, were deficient in oxygen but still capable of supporting most aquatic life. No evidence of hypoxia (<2.0 mg/l O2) or anoxia (<0.2 mg/l O2) was found. Dissolved oxygen conditions in a number of estuaries continue to improve, probably due to improved municipal waste water treatment. The implementation of measures contained in both the Nitrates and Urban Waste Water Treatment Directives, together with those of the Water Framework Directive, should ensure areas of oxygen deficiency are eliminated from Irish waters.  相似文献   

20.
This paper continues the investigations of Clemens and Hartwig from 1992 on the proportion of garbage used as nesting material in the Kittiwake colony at Bulbjerg in the Jammerbugt in Northwest Denmark. Whereas in the year 1992 plastic garbage items were included in 39.3% of 466 Kittiwake nests in the Bulbjerg colony, in 2005 57.2% of 311 nests contained plastic debris. Although it has been forbidden to dispose of plastic garbage into the marine environment since the implementation of the MARPOL 73/78-Agreement/Annex V (Regulation for the Prevention of Pollution by Ship Waste) of 1989 and especially since the declaration of the North Sea as a MARPOL-Special Area for garbage in 1991, the pollution of the oceans and the North Sea is still an ubiquitous problem, particularly with regard to plastic waste. Plastic waste is presumably not used preferentially for nest-building, but in the context of available nesting material in the waters surrounding the breeding colony. Therefore the share of garbage parts in nests of certain species of birds is an indicator of the amount of waste in the natural environment in the vicinity of their breeding site.  相似文献   

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