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1.
Antifouling paint residues collected from the hard-standings of a marine leisure boat facility have been chemically characterised. Scanning electron microscopy revealed distinct layers, many containing oxidic particles of Cu and Zn. Quantitative analysis indicated concentrations of Cu and Zn averaging about 300 and 100 mg g−1, respectively, and small proportions of these metals (<2%) in organometallic form as pyrithione compounds. Other trace metals present included Ag, Cd, Cr, Ni, Pb and Sn, with maximum concentrations of about 330, 75, 1200, 780, 1800 and 25,000 μg g−1, respectively. Estuarine sediment collected near a boatyard contained concentrations of Cu and Zn an order of magnitude greater than respective concentrations in “background” sediment, and mass balance calculations suggested that the former sample was contaminated by about 1% by weight of paint particles. Clearly, antifouling residues represent a highly significant, heterogeneous source of metallic contamination in the marine environment where boating activities occur.  相似文献   

2.
Forty-three sediment samples were collected from the beaches of Miri City, Sarawak, Malaysia to identify the enrichment of partially leached trace metals (PLTMs) from six different tourist beaches. The samples were analyzed for PLTMs Fe, Mn, Cr, Co, Cu, Ni, Pb, Sr and Zn. The concentration pattern suggest that the southern side of the study area is enriched with Fe (1821–6097 μg g−1), Mn (11.57–90.22 μg g−1), Cr (51.50–311 μg g−1), Ni (18–51 μg g−1), Pb (8.81–84.05 μg g−1), Sr (25.95–140.49 μg g−1) and Zn (12.46–35.04 μg g−1). Compared to the eco-toxicological values, Cr > Effects range low (ERL), Lowest effect level (LEL), Severe effect level (SEL); Cu > Unpolluted sediments, ERL, LEL; Pb > Unpolluted sediments and Ni > ERL and LEL. Comparative results with other regions indicate that Co, Cr, Cu, Ni and Zn are higher, indicating an external input rather than natural process.  相似文献   

3.
Water column profiles and near-bed time series of pressure, current velocity, suspended-particulate matter (SPM) concentration and seawater temperature and salinity were collected during three short cruises carried out in May 2005 in the shoreface and inner shelf area adjacent to Cassino Beach, southern Brazil. The measurements were part of the Cassino Experiment, a project conducted at an open, sandy coastal area known for the occurrence of patches of fairly large amounts of muddy sediments that are sporadically fluidized, transported onshore and eventually stranded on the beach. The study area is close to the Patos Lagoon mouth, being influenced by its water and suspended-sediment discharge. The presence of the Patos Lagoon outflow on the inner shelf was detected in one of the cruises (May 13) through measurements of near-surface salinity: while close to shore salinity was 29.4, a minimum value of 13.8 was measured at ∼10 km from the coast. Four days later, no trace of the plume was detected in the area. Regarding seawater temperature, no large temporal or spatial variability was documented with measured values ranging from 19.3 to 20 °C. Water column currents were prominently to N and NE, except at the outermost station, located ∼42 km from the coast, where NW-directed flows were observed at surface and mid-depth. Maximum near-bed current velocity oscillated between 18 and 42 cm s−1 in the east–west direction and between 14 and 42 cm s−1 in the north–south direction. Near-surface concentration of SPM oscillated between 11 and 99 mg L−1, in general one order of magnitude lower than near-bed values. However, near-bed concentration of SPM showed large spatial variability: the highest value (2200 mg L−1) was yielded by a water sample collected at ∼8 m water depth, at a station located ∼2 km away from the shoreline; two water samples collected 500 m, apart from this station, yielded SPM concentrations of 148 and 205 mg L−1, one order of magnitude lower. Spectral analyses of near-bed current speed and SPM concentration indicate the relevance of oscillations in the low-frequency (<0.05 Hz) range. Detailed sampling of bottom sediment indicated that in May 2005 the mud patch was centered at ∼8.5 m water depth.  相似文献   

4.
The study of trace elements (Cu, Zn, Pb, As, Hg) and butyltin concentrations in the sediments of Port Camargue enabled assessment of the levels and history of the contamination of the largest European marina linked with the use of antifouling paints. Surface sediments near the boat maintenance area were heavily contaminated with up to 1497 μg g−1 of Cu, 475 μg g−1 of Zn, 0.82 μg g−1 of Hg, 94 μg g−1 of Pb and over 10,000 ngSn g−1 of tributyltin (TBT). High concentrations of Hg and TBT indicate ongoing sources of these elements despite the ban on their use as biocides in paints. Sediment cores provided records of contamination since 1969. The peak concentrations of As, Hg, Pb and TBT in the sediment profile reflect their presence on boat hulls when the marina was built at the end of the 1960s. Degradation of TBT in the sediments near the boat maintenance area is slow compared to other less contaminated area of the marina.  相似文献   

5.
Admiralty Bay (Antarctica) hosts three scientific stations (Ferraz, Arctowski and Macchu Picchu), which require the use of fossil fuel as an energy source. Fossil fuels are also considered the main source of pollution in the area, representing important inputs of major pollutants (organic compounds) and trace metals and metalloids of environmental interest. Accordingly, this work presents the results of As, Cd, Cr, Cu, Ni, Pb and Zn in sediment profiles from Admiralty Bay. The sediment results from Ferraz station were slightly higher than the other sampling sites. The highest contents were observed for Cu and Zn (from 44 to 89 mg kg−1). Otherwise, by using enrichment factors and geochronology analysis, the most relevant enrichment was observed for As in the samples collected close to the Ferraz station, indicating that increasing As content may be associated with the activities associated with this site.  相似文献   

6.
The newly introduced polychaete Linopherus canariensis Langerhans, 1881 was found in the Lake of Faro (NE Sicily), during a study comparing the macrobenthos in artificial modules with a neighboring sandy bottom assemblage. Of a total of 4465 specimens, almost 6% showed morphological variation related to branchial turfs and mean body size. The sandy bottom exhibited an average density of 41.86 ind L−1 and a wet biomass of 30.35 mg L−1, whereas the artificial substratum reached levels of 205.29 ind L−1 and 318.44 mg L−1. The highest estimated immigration rate was 3.7 ind L−1 d−1 (5.8 mg L−1 d−1). In the artificial microhabitat, 0.4% of the population showed mid-anterior fragmentation, with anterior- (2%), mid- (<1%) and posterior- (1%) regenerating lineages, which contributed significantly to the dispersion ability of this species. L. canariensis was a selective micro-deposit feeder, even under conditions of reduced sediments. Linopherus was found to be a new potential invader of stressed environments that is probably tied to the import of oysters.  相似文献   

7.
The abundance and distribution of rare earth elements (REE) and their signatures in the Vigo Ria were studied from 50 samples of surface sediments and related to the geological formation in its watershed. The total amount of REE in the Ria is heterogeneous. It ranges from 220 mg kg−1 in the southern middle Ria margin in the vicinity of the Galiñeiro geological shore complex, which contains REE-enriched minerals, to 2 mg kg−1 near the Ria mouth due to dilution with high levels of carbonated biogenic particles (31% of Ca). Rare earth elements of the Ria sediments are considerably enriched in light-REE relative to heavy-REE (a LREE/HREE ratio of 9.7±1.6) and also show a slightly negative Eu-anomaly. Low European shale normalised REE patterns were distinguished in the innermost sediments of Vigo Ria, but were not correlated with Al. This suggests a minor contribution of REE from upstream freshwater inputs to the sediments in the middle Vigo Ria zone. Normalised REE ratios in the middle Ria imply that fine particles enriched in REE may be exported from the Ria to shelf mud patches and REE can be useful as sediment tracers of Ria input on the shelf.  相似文献   

8.
Mobilisation of sedimentary monosulfidic black ooze (MBO) may result in rapid deoxygenation and acidification of surface waters, and release of potentially toxic metals. This study examines the extent and nature of MBO accumulation in the Geographe Bay area, Western Australia. MBO accumulations were found to be widespread in benthic sediments of the Geographe Bay area with acid-volatile sulfide (AVS) contents as high as 320 μmol g−1. The MBO materials often had unusually high dissolved sulfide (S−II) concentrations in their pore-waters (up to 610 mg L−1) and elevated elemental sulfur (S0) contents (up to 51 μmol g−1). Dissolved S−II is able to accumulate due to limited iron availability and S0 is largely its partial oxidation product. The availability of organic carbon and Fe limited MBO accumulation at many sites. A comparison of AVS and simultaneously extracted metal (SEM) concentrations has shown that metals are likely to be bound in sulfide complexes.  相似文献   

9.
The deterioration of sediments is a serious environmental problem. Controlling nutrient release fluxes from sediments is important to alleviating eutrophication and to reducing terrigenous nutrient loads. The purpose of this study was to evaluate the phosphate removal performance of granulated coal ash (GCA) from seawater, which is produced from coal thermal electric power generation. Batch experiments were carried out to investigate the removal kinetics of phosphate from seawater under both oxic and anoxic conditions. Phosphate was removed well from seawater under both oxic and anoxic conditions. The adsorption isotherm for phosphate revealed that GCA could remove phosphate effectively from seawater above a concentration of 1.7 μmol L−1. GCA can reduce the concentration of phosphate in seawater effectively under anoxic conditions where iron type adsorbents cannot be applied. Therefore, GCA could potentially be used to adsorb phosphate in the organically-enriched sediment, which generally occurs under highly reductive conditions.  相似文献   

10.
Antifouling paint fragments collected from marinas and leisure boat maintenance facilities and in the vicinity of abandoned boats have been chemically characterised. High concentrations of Cu (23-380 mg g−1) and Zn (14-160 mg g−1) in the samples (n = 14) are consistent with the use of these metals in the principal biocidal and non-biocidal pigments in contemporary antifouling formulations. Up to about 2% and 7% of the respective metals were solvent-extractable, suggesting that organo-forms of Cu and Zn (e.g. pyrithiones) were also present. Of the organic biocides, dichlofluanid was present in most samples and at concentrations up to about 20 mg g−1. Chlorothalonil and Irgarol 1051® were only detected in one and four cases, respectively, and Sea Nine 211® was not detected in any sample. Results are discussed in terms of UK legislation regarding biocide usage and the likely effects and fate of discarded paint particles in coastal environments where boats are repaired or moored.  相似文献   

11.
In this paper we present the concentrations of Hg, Cd, Se, Pb, Cu, Mn, Zn and Fe in organs of 6 non-common specimens of cetaceans that were stranded along the Israeli Mediterranean coast (IMC), during 2002–2010: two fin whales, one minke whale, one Cuvier’s beaked whale, one rough-toothed dolphin, and one Risso’s dolphin. Most of the specimens were calves stranded by accident. Concentrations of Hg and Cd were low in tissues of the baleen whales and higher in the toothed whales, with maximum concentrations of 1067 mg kg−1 Hg in the liver of the Risso’s dolphin and 29 mg kg−1 Cd in the kidney of the Cuvier’s beaked whale. As far as we are aware, this is the first report of trace elements in baleen whales in the Eastern Mediterranean, and the first report of trace elements in minke whale and rough-toothed dolphin in the Mediterranean.  相似文献   

12.
Marine sediment may contain both settled phytoplankton and benthic microalgae (BMA). In river-dominated, shallow continental shelf systems, spatial, and temporal heterogeneity in sediment type and water-column characteristics (e.g., turbidity and primary productivity) may promote spatial variation in the relative contribution of these two sources to the sediment organic matter pool available to benthic consumers. Here we use photosynthetic pigment analysis and microscopic examination of sediment microalgae to investigate how the biomass, composition, and degradation state of sediment-associated microalgae vary along the Louisiana (USA) inner shelf, a region strongly influenced by the Mississippi River. Three sandy shoals and surrounding muddy sediments with depths ranging from 4 to 20 m were sampled in April, August, and October 2007. Pigment composition suggested that sediment microalgae were primarily diatoms at all locations. We found no significant differences in sediment chlorophyll a concentrations (8–77 mg m−2) at the shoal and off-shoal stations. Epipelic pennate diatoms (considered indicative of BMA) made up a significantly greater proportion of sediment diatoms at sandy (50–98%) compared to more silty off-shoal stations (16–56%). The percentage of centric diatoms (indicators of settled phytoplankton) in the sediment was highest in August. Sediment total pheopigment concentrations on sandy stations (<20 mg m−2) were significantly lower than concentrations at nearby muddy stations (>40 mg m−2), suggesting differences in sediment microalgal degradation state. These observations suggest that BMA predominate in shallow sandy sediments and that phytodetritus predominates at muddy stations. Our results also suggest that the relative proportion of phytodetritus in the benthos was highest where phytoplankton biomass in the overlying water was greatest, independent of sediment type. The high biomass of BMA found on shoals suggests that benthic primary production on sandy sediments represents a potentially significant local source of sediment microalgal carbon that may be utilized by benthic consumers in continental shelf food webs.  相似文献   

13.
In this paper, the vertical variations of heavy metal elements (including Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in the sediments of Songhua Lake are analyzed using sediment cores. A 70‐year evolutionary history of these heavy metal elements in Songhua Lake is described and the sources of the heavy metals in the sediments are investigated by evaluating the pollution characteristics of the metals in terms of their enrichment coefficients and geoaccumulation indexes. The results indicate that Cr, Cu, Mn, Ni, Pb, and Zn in the sediments originated mainly from basin erosion and were transported to the lake by rivers. Cd and Hg in the sediments also originated from basin erosion that occurred prior to the mid‐1990s, and these sediments have since been overlaid by artificial pollution. The distribution of heavy metals in the sediments of Songhua Lake is influenced by many factors, including sediment composition, the relative importance of fluvial input, and artificial pollution.  相似文献   

14.
Field experiments were carried out to evaluate the effect of Granulated Coal Ash (GCA) on remediation of coastal sediments in terms of removing phosphates and hydrogen sulfide. Phosphate concentrations in the sediment were kept below 0.2 mg/l after the application of GCA, whereas those in the control sites increased up to 1.0 mg/l. The concentration of hydrogen sulfide in the sediment was maintained at almost zero in the experimental sites (GCA application sites) for over one year, whereas it ranged 0.1–2.4 mg S L−1 in control sites. Meanwhile, individual number of benthos increased in the experimental sites by several orders of magnitude compared to the control sites. The major process involved in hydrogen sulfide removal by GCA was thought to be the increase in pH, which suppresses hydrogen sulfide formation. From our findings, we concluded that GCA is an effective material for remediating organically enriched coastal sediment.  相似文献   

15.
The distributions of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in the aqueous phase, suspended particulate matter (SPM), sediment, and pore water of the Daliao River Estuary in Liaodong Bay, Bohai Sea (China). Total PAH concentrations ranged from 139.16 to 1717.87 ng L−1 in surface water, from 226.57 to 1404.85 ng L−1 dry weight in SPM, from 276.26 to 1606.89 ng g−1 dry weight in sediments, and from 10.20 to 47.27 μg L−1 in pore water. PAH concentrations were at relatively moderate levels in water, SPM, sediment and pore water in comparison with those reported for other estuary and marine systems around the world. Sedimentary PAH concentrations decreased offshore owing to active deposition of laterally-transported river-borne particles. PCA analysis of the possible PAH source suggested petrogenic and pyrolytic PAH inputs in the studied region.  相似文献   

16.
The aim of this study is to explore the contribution of living phytoplankton carbon to vertical fluxes in a coastal upwelling system as a key piece to understand the coupling between primary production in the photic layer and the transfer mechanisms of the organic material from the photic zone. Between April 2004 and January 2005, five campaigns were carried out in the Ría de Vigo (NW Iberian Peninsula) covering the most representative oceanographic conditions for this region. Measurements of particulate organic carbon (POC), chlorophyll-a (chl a), phaeopigments (phaeo), and identification of phytoplankton species were performed on the water column samples and on the organic material collected in sediment traps.The POC fluxes measured by the sediment traps presented no seasonal variation along the studied period ranging around a mean annual value of 1085±365 mg m−2 d−1, in the upper range of the previously reported values for other coastal systems. The fact that higher POC fluxes were registered during autumn and winter, when primary production rates were at their minimum levels points to a dominant contribution of organic carbon from resuspended sediments on the trap collected material. On the contrary, fluxes of living phytoplankton carbon (Cphyto) and chl a clearly presented a seasonal trend with maximum values during summer upwelling (546 mg m−2 d−1 and 22 mg chl a m−2 d−1, respectively) and minimum values during winter (22 mg m−2 d−1 and 0.1 mg chl a m−2 d−1, respectively). The contribution of Cphyto to the vertical flux of POC ranged between 2% and 49% in response to the pelagic phytoplankton community structure. Higher values of Cphyto fluxes were registered under upwelling conditions which favour the dominance of large chain-forming diatoms (Asterionellopsis glacialis and Detonula pumila) that were rapidly transferred to the sediments. By contrast, Cphyto fluxes decreased during the summer stratification associated with a pelagic phytoplankton community dominated by single-cell diatoms and flagellates. Minimal Cphyto fluxes were observed during the winter mixing conditions, when the presence of the benthic specie Paralia sulcata in the water column also points toward strong sediment resuspension.  相似文献   

17.
Our investigation on macrophytes in Lake Qattieneh, a large, shallow reservoir in western Syria, is a first assessment of ecological status of this lake. We studied spatial distribution patterns of aquatic macrophyte vegetation and heavy metal concentrations to determine if they can be used as indicators of point sources of pollution. Industrial and municipal point sources at the lake shore increase nutrient load and contamination by heavy metals. Water analyses revealed high concentrations of some heavy metals at some littoral sites: Ni 88.7 μg L−1, Cr 49.99 μg L−1, Co 14.38 μg L−1, and Cu 11.65 μg L−1. Despite hypertrophic conditions and high heavy metal contamination, we recorded several submerged macrophyte species with heterogeneous spatial distribution patterns. Whereas Potamogeton pectinatus L. dominates in the eastern part of the lake, near industrial point sources, both Myriophyllum spicatum L. and Potamogeton lucens L. form extended patches in the western part of the lake. The shallow, littoral areas near villages are dominated by Ranunculus trichophyllus Chaix in Villars and Ceratophyllum demersum L. The west-east gradient in nutrient and heavy metal concentrations in waters and sediments are reflected by the spatial distribution of submersed species. While the heavy metal concentrations of the water body vary considerably in different seasons, the contents in submersed macrophytes integrate seasonal variations of longer time periods. Spatial distribution and tissue accumulation of littoral macrophyte species reflect the environmental conditions at respective sites such as heavy metal contents in water and sediment.  相似文献   

18.
The Gulf of Gdańsk is influenced by heavy metals of anthropogenic origin. In this study, temporal concentration changes of Pb, Zn, Cd, and Cu were studied in six, 50 cm long sediment cores. The main aim of the study was to concentrate on the history of Pb fluxes and Pb isotopic composition (206Pb/207Pb and 208Pb/206Pb) to trace Pb sources. The lowest Pb concentrations (19 μg g−1) were measured in sediments deposited circa 1860, while the highest Pb concentrations (63–147 μg g−1) were measured in sediments deposited between 1960s and 70s. Pre-industrial Pb fluxes were 7 Pb m2 year−1, while after WWII they reached 199 Pb m2 year−1. Highest 206Pb/207Pb ratios (∼1.22) were measured in the oldest sediment layers, and the lowest 206Pb/207Pb ratios (∼1.165) were measured in the sediments deposited in 1970s–90s. During the period of highest Pb contamination, the anthropogenic Pb fraction reached up to 93%. A general discussion of the Pb sources, emissions, and loads for Poland is included.  相似文献   

19.
Waters and sediments from the Potiguar Basin (NE Brazilian coast) were investigated for the presence and nature of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons. The region receives treated produced waters through a submarine outfall system serving the industrial district. The total dispersed/dissolved concentrations in the water column ranged from 10-50 ng L−1 for ∑16PAH and 5-10 μg L−1 for total aliphatic hydrocarbons. In the sediments, hydrocarbon concentrations were low (0.5-10 ng g−1for ∑16PAH and 0.01-5.0 μg g−1 for total aliphatic hydrocarbons) and were consistent with the low organic carbon content of the local sandy sediments. These data indicate little and/or absence of anthropogenic influence on hydrocarbon distribution in water and sediment. Therefore, the measured values may be taken as background values for the region and can be used as future reference following new developments of the petroleum industry in the Potiguar Basin.  相似文献   

20.
The temporal and spatial distribution of total petroleum hydrocarbons (TPH) in the seawater of Tianjin Bohai Bay during 1996-2005 was investigated for the first time. TPH concentrations in 480 seawater samples collected from 16 stations during a 10-year span were quantified by ultra-violet fluorescence spectroscopy. Petroleum hydrocarbons were ubiquitous in the seawater, and their concentrations were highly variable, ranging from 23.7 to 508 μg L−1. TPH concentrations in the seawater varied with seasons, showing a decreasing order of winter > spring > summer. Over the 10-year period, TPH at all stations steadily decreased. The highest values obtained were at stations near the port areas and Dagu outfall where shipping activities and land-based waste water discharges were the major sources of pollution. Our results provided the background information on the extent of TPH contamination in the seawater and highlighted the need to further control TPH pollution in Tianjin Bohai Bay.  相似文献   

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