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1.
Following the spill of fuel oils from the New Carissa in February 1999, approximately 300 km of beaches on the Pacific coast of North America were surveyed. A long-term observation program focused on the documentation of stranded tar balls in the vicinity of the spill site. Systematic beach surveys which were conducted over the period March 1999 to April 2001 and semi-logarithmic scale, time-series plots proved the most useful format for identifying trends. Beach monitoring continued through to August 2001. by which time 212 tar balls had been analyzed by GC/MS for their chemical characteristics. The samples of tar balls collected between February 1999 and August 2001 were qualitatively compared with New Carissa source oils (NCSO) and 101 (48%) were not consistent with NSCO. The presence of tar balls that are not related to an incident can confound attempts to define cleanup or endpoint criteria and to assess possible injury to natural resources.  相似文献   

2.
Tar balls, according to their densities, the prevailing temperature and their degree of weathering, are observed as floating, sinking, or are washed onto the beaches in the marine environment. To characterize the differences between floating and sunken tar balls, samples were analysed by IR, H-nmr, GC and GC/MS techniques. Hexane, benzene and methanol solubilities as well as densities were measured. The degree of weathering of the tar balls was investigated in terms of the losses of n-paraffinic/aromatic hydrocarbons. The ratio of paraffinic/aromatic hydrocarbon concentrations was calculated by IR and H-nmr whereas pristane/phytane ratios were estimated from GC measurements. The comparison of some high molecular weight, but minor, components between the major n-paraffins was obtained from GC/MS measurements.  相似文献   

3.
Trinidad and Tobago beaches were periodically sampled for tar between July 1980 and September 1981. This project was carried out by the Institute of Marine Affairs in cooperation with the United Nations. The Caribbean coasts of both islands were almost pristine, whereas pollution on the Atlantic coast beaches was comparable to that of other coasts along major tanker routes. The source of high tar concentrations on the Atlantic coasts may be attributed to the residues from tanker bilge cleanings, which are carried along the South Equatorial Current, eventually to strand on the islands' beaches. In the dry season (January to April) north-westerly currents and north-easterly winds prevail and more tar strands on Trinidad than on Tobago. In the wet season (June to November), however, when currents are more northerly and south-easterly wind prevail, the reverse situation holds and more tar strands on Tobago.  相似文献   

4.
Amounts of tar stranded on Florida beaches were determined periodically over one year (September 1979–October 1980). Results show that tar fouling of southeast Florida beaches is an order of magnitude greater than the rest of the state. This may result from the extensive ship traffic in the Straits of Florida. There is no evidence that any Florida beaches received increased amounts of tar as a result of the 1979 Ixtoc-1 blowout in the southern Bay of Campeche. There is also no evidence that the amounts of tar on southeast Florida beaches have increased over amounts measured in API studies conducted in 1958 and 1971.  相似文献   

5.
Ten fungal species isolated from tar balls collected from the beaches of Oman were tested for their abilities to grow and degrade n-alkanes and crude oil. The abilities of Aspergillus niger, A. ochraceus and Penicillium chrysogenum to degrade n-alkanes (C13-C18), crude oil were compared and their mycelial biomass was measured. Significant differences were found in the utilization of C15, C16, C17 and C18 by the three fungi. Similarly, significant differences we found in the amount of biomass produced by the three fungi growing on C13, C17, C18 and crude oil. The correlation coefficient of biomass and oil utilization was not statistically significant for Aspergillus niger, significant for Aspergillus terreus and highly significant for P. chrysogenum.  相似文献   

6.
Monitoring of sandy beaches after the Prestige oil spill revealed thick subsurface layers (up to 1 m thick) of grey-coloured sand. These horizons were sometimes found under more than 3 m of clean sand. Examination of the sand by electron microscopy confirmed that the colouring was due to oil-coated sand grains, and revealed a sequence of degradation of buried oil. Further analysis of the sand revealed high concentrations of hydrocarbon in the oil-coated sand and that the main biomarkers were indicative of biodegradation, even though the oil was buried.A set of experiments was designed to analyze the evolution of oil from tar balls to coatings. The results revealed that biodegradation is a secondary process in the changes that take place in the buried oil, and that water flow slows down the appearance of grey sand and that low salinity may hinder the oil degradation process.  相似文献   

7.
The BP MC252 well failure in the Gulf of Mexico, April 2010 caused concern for crude oil and polycyclic aromatic hydrocarbon (PAHs) exposure along the sandy beaches of the Florida Panhandle. We began collections of Coquina clams (Donax spp.) from the surf zone of Florida Panhandle beaches to monitor PAH contamination to compliment analysis of surf zone sand samples. These clams had higher levels of PAHs relative to ambient sand, and this allowed us to continue to monitor PAH levels after sand concentrations fell below limits of detection. PAH levels in the Coquina tissues were highly variable, perhaps indicative of the heterogeneous distribution of oil and tar on the beaches and exposure to tar particles. Overall, PAH levels decreased continuously in both sand and Coquina tissues, reaching limits of detection within one and two years respectively after oil landed on Florida Panhandle beaches. Our work suggests these surf zone molluscs may be used to monitor pollutant exposure along high energy sandy beach shorelines.  相似文献   

8.
Stranded pelagic tarballs were collected from two beaches on the island of Bermuda from January 1982 until June 1983. A significant decrease in the quantity of stranded tarballs was noted after comparison to data collected from the same beaches in 1978-79. There is also an indication that the amount of tar arriving on Bermuda is less than or equal to the levels measured in 1971-72. The decline in the quantity of pelagic tar in the Sargasso Sea is attributed to a reduction in the operational discharges of oil tankers and a decrease in the occurrence of maritime oil spills since 1980.  相似文献   

9.
Measurement of tar ball concentrations of samples taken on twelve monthly cruises from 120 stations around the south-western coast of South Africa shows that this area is relatively free of floating tar. A tanker collision resulted in a major oil spill halfway through the programme, allowing the movement and dispersion of tar balls to be followed.  相似文献   

10.
The major process involved in the removal of stranded petroleum residues or ‘tar lumps’ from sandy high energy beaches is the adsorption of sand and shell particles to the residues effecting a density change. This results in transport off the beach, sinking, and sometimes burial of the tar in sublittoral sediments.  相似文献   

11.
During the crossing of the Atlantic by the cutter, Penny Royal last summer, regular samples were taken of tar balls floating in the water. They were found in every sample and ranged in size from 0·35 to 20 mm diameter; larger masses were seen but not collected. Floating liquid oil was observed on four occasions.  相似文献   

12.
A consolidated picture of oil pollution for the northern Indian Ocean is presented. Oil slicks were sighted on 5582 observations, about 83.5% of the total observations of 6689. The range of concentrations, of the floating tar balls, is 0–6.0 mg/m2 in the Arabian Sea. Similarly, the oil tanker route in the Bay of Bengal has the range of 0–69.75 mg/m2. North of this route, the Bay of Bengal is comparatively free from this floating tar. Mean concentrations of dissolved and dispersed hydrocarbons for 0–20 m are 32.5 and 24.1 μg kg?1, respectively, in the Arabian Sea and the Bay of Bengal.  相似文献   

13.
Petroleum pollution in the form of floating tar balls and dissolved or dispersed hydrocarbons has been monitored off the south-west coast of Puerto Rico on a weekly basis since November 1980. Tar ball abundance estimates agree well with previously published data for the area. Dissolved/dispersed hydrocarbon concentrations are close to, but below, those found in the Mediterranean Sea and considerably lower than those for more polluted areas. Tar ball abundance is closely related to the intensity of southerly winds. Dissolved/dispersed hydrocarbon concentrations are highest during the fall and coincident with the highest surface water temperatures.  相似文献   

14.
Beaches of tropical island coasts exhibit high levels of diversity in composition and form in comparison with their continental counterparts. To investigate the nature and origin of this diversity, individual beach morphology and sedimentology was investigated in the British Virgin Islands (BVI), a Caribbean archipelago of > 60 high volcanic and low reef islands. The islands exhibit a diversity of orientations (some facing the Atlantic and some the Caribbean), elevation and gradient, rock type and wave energy. An examination of 100 beaches in the archipelago revealed a first-order division into sand (70 beaches) and coral rubble (30 beaches). These beaches occur in seven planform types (determined by the antecedent geological framework) and are further subdivided according to shoreface type (seagrass, sandy shoreface, or reef). Mainland-attached headland-embayment beaches are the most common form of sand beach while coral rubble beaches usually occur as barriers that enclose salt ponds and wetlands. Among sand beaches, carbonate content is greatest on Atlantic-facing beaches, and coral rubble beaches are more common on Caribbean-facing beaches. Grain size characteristics on sandy beaches are highly variable and range from fine to very coarse sands while coral rubble beaches range up to boulder-sized clasts. The local source material is a primary determinant of sediment composition. The local factors such as the underlying geology, source and availability of sediments are the primary determinants of beach form, composition and texture in the BVI. Oceanographic and climatic conditions such as the prevailing easterly trade winds and waves which seasonally range in direction from east-northeast to southeast as well as beach orientation to Atlantic- or Caribbean-facing waves also contribute to the variability, but in a secondary role. © 2019 John Wiley & Sons, Ltd.  相似文献   

15.
During April 1996-May 2005, 2343 oiled seabird corpses were recorded in beach surveys conducted on Sable Island, Nova Scotia. One hundred eighty-three samples of oil were collected from the beaches and from the feathers of bird corpses. Gas chromatographic (GC/FID) analysis was used to identify generic oil type and likely marine source. During this period, at least 74 marine oil discharge events were probably responsible for beached pelagic tar and contamination of seabird corpses found on Sable Island, of which 77.0% were crude oils, 14.9% were fuel oils, and 8.1% were bilge oil mixtures. While fuel and bilge oils may be discharged by all vessel and platform types, crude oil discharges are associated with tanker operations. This study demonstrates that oiling of the sea from tankers remains a serious wildlife issue in the Northwest Atlantic.  相似文献   

16.
The beetle Phaleria maculata is a common inhabitant of the upper intertidal fringe of Chilean beaches. Anthropogenic intervention in coastal areas has increased intensely, leading to changes in the flora and fauna of sandy beaches. To examine the impact of human activities on P. maculata, we studied several beaches along the northern Chilean coast. Beaches were characterized based on morphodynamics and the level of intervention, leading to the estimation of an “Urbanization Index” based on various indicators. The analysis showed a significant inverse correlation between the rate of urbanization and night sky quality. Larval and adult beetles were almost absent on beaches with high levels of urbanization. The results of simple and multiple correlations based on nMDS ordination showed an inverse relationship between increases in urbanization and the abundance of beetles. Because darkling beetles are very sensitive to human interventions on sandy beaches, we suggest that they are ideal indicator organisms for the health of these environments.  相似文献   

17.
The persistence and character of stranded oil on coarse-sediment beaches   总被引:2,自引:0,他引:2  
Small amounts of oil that can persist for decades in the intertidal zone of coarse-sediment beaches have been documented in a few well-studied cases. Oil that survives attenuation over the short-term (weeks to months) will persist until there is a change in the environmental conditions, as might occur where there is a seasonal storm-wave climate or as a beach undergoes long-term (erosional) changes. Oil residues can persist on the beach surface as tar mats, asphalt-like pavements, or as veneers on sediment particles or hard surfaces. Subsurface oil residues can persist in similar forms or as fill or partial fill of the pore spaces between coarse-sediment particles. Oil penetrates until it reaches fine-grained sediment, the water table, bedrock, or other penetration-limiting layers. Amounts of persistent oil are very small fractions of the volumes that were originally stranded and these protected residues can continue to biodegrade as they become thinner and more discontinuous.  相似文献   

18.
Beaches are common features of many rocky shorelines and can be considered to be constrained by the underlying geology. In mesotidal to macrotidal areas the slope of the substrate and sediment supply are the primary factors in constraining the size and development of beaches on shore platforms. In microtidal settings it is not known if these factors are wholly responsible for determining the presence of beaches on shore platforms, nor the contribution of other factors such as hydrodynamics. The microtidal coast of Victoria, Australia, is surveyed in this study in order to quantify the morphological boundary conditions that constrain beach development on semi‐horizontal shore platforms. An ample sediment supply indicates that the underlying geology is controlling the presence and absence of beaches. Where beaches occur they always overlie a rock ramp which is the steepest part of the platform. The two most important morphological constraints were platform width and height both of which significantly correlated with beach volume. An elevational threshold exists at just over +1.0 m where beaches cannot accumulate. Below this threshold, platform width appears to be the principle constraining factor in beach accumulation. An evolutionary model is inferred which suggests that dissipation of wave energy associated with platform widening plays an important role in allowing beaches to accumulate. The model suggests beaches on platforms will be particularly sensitive to sea level rise. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

19.
Environmental variables and their association with faecal coliform and streptococci densities were investigated at a number of Sydney's metropolitan beaches. High variability in faecal coliform and faecal streptococci densities was observed at most beaches. The ability of the various models to explain the observed variation in faecal coliform or streptococci levels was relatively low, although they did provide an insight into the more influential environmental factors involved. Rainfall has the single most important effect on faecal coliform and streptococci densities at Sydney beaches. Whether this is due to increased stormwater runoff at the beaches, increased discharge through the outfalls (both the deepwater ocean outfalls and the few remaining shoreline outfalls), or a combination of both is unclear and is likely to depend on the individual beach being considered. Elevated levels of faecal coliforms and streptococci are still occasionally observed at some beaches, but these levels are usually not as high nor as frequent as they were prior to commissioning of the deepwater outfalls. The significant associations of current and plume entrapment with faecal coliform and streptococci densities at some Sydney beaches suggest that under certain conditions, effluent from the deepwater ocean outfalls can still influence faecal coliform and streptococci densities at these beaches.  相似文献   

20.
Our aim was to examine the health effects on bathers from exposure to recreational seawater on three beaches with different microbiology quality and bather density through a cohort study. An initial questionnaire and a 10 day follow up were used. Univariate and backward logistic regression analyses were used to asses the risk of developing symptoms or diseases among the bathers. In total, 3805 bathers were included in the study and 149 samples were collected from the three beaches. Despite all the beaches being characterized of high quality the levels of bacterial indicators differed among them. Health effects among bathers were not associated with bacterial indicators. A statistically significant increased risk for symptoms related to respiratory illness, gastroenteritis, medical consultation and use of medication was observed among bathers at the higher bather density beaches. Beach bather numbers should always be taken into account when considering a risk assessment approach.  相似文献   

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