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1.
The response of metal accumulation in coral Tubastraea coccinea to various degrees of metal enrichment was investigated from the Yin-Yang Sea (YYS) receiving abandoned mining effluents, the Kueishan Islet (KI) hydrothermal vent field, and the nearshore area of remoted Green Island (GI). The concentrations of most dissolved metals were highest in seawater at YYS, followed by KI, and then GI, showing the effects of anthropogenic and venting inputs on metal levels. Five metals (Co, Fe, Mn, Ni, and Zn) yielded significant differences (p < 0.05) among the skeleton samples. We identified similar patterns in the metal–Ca ratios, indicating that the elevated metals in skeletons was a consequence of external inputs. The coral tissues were relatively sensitive in monitoring metal accumulation, showing significant differences among three locations for Cd, Co, Cu, Fe, Pb, Ni, and Zn. Specific bioconcentration factors provided strong support for the differential metal accumulation in skeletons and tissues.  相似文献   

2.
Dredging related metal bioaccumulation in oysters   总被引：1，自引：0，他引：1  
Bivalves are regularly used as biomonitors of contaminants in coastal and estuarine waters. We used oysters to assess short term changes in metal availability caused by the resuspension of contaminated sediments. Sydney Rock Oysters, Saccostrea glomerata, were deployed at multiple sites in Port Kembla Harbour and two reference estuaries for 11 weeks before dredging and for two equivalent periods during dredging. Saccostrea experienced large increases in accumulation of zinc, copper and tin during dredging in the Port relative to oysters deployed in reference estuaries. Lead and tin were found to be permanently elevated within Port Kembla. We present a clear and un-confounded demonstration of the potential for dredging activities to cause large scale increases in water column contamination. Our results also demonstrate the usefulness of external reference locations in overcoming temporal confounding in bioaccumulation studies.  相似文献   

3.
This study introduces an innovative method for biomonitoring using giant kelp (Macrocystis pyrifera) sieve tube sap (STS) metal concentrations as an indication of pollution influence. STS was sampled from fronds collected from 10 southern California locations, including two reference sites on Santa Catalina Island. Using ICP-MS methodology, STS concentrations of 17 different metals were measured (n = 495). Several metals associated with pollution showed the highest STS concentrations and most seasonal variation from populations inside the Port of Los Angeles/Long Beach. Lowest concentrations were measured at less-urbanized areas: Santa Catalina Island and Malibu. Some metals showed a spatial gradient in STS metal concentration with increasing distance from point sources (i.e. Los Angeles River). Cluster analyses indicate that polluted seawater may affect kelp uptake of metals essential for cellular function. Results show that this method can be useful in describing bioavailable metal pollution with implications for accumulation within an important ecosystem.  相似文献   

4.
Intersexuality has been widely reported in crustaceans with several mechanisms being directly or indirectly held responsible for its occurrence, amongst which pollution. No mechanistic relationship between metals and intersex has ever been established. Also the incidence of intersex in populations of the same invertebrate species in a latitudinal gradient has never been studied so far. Three populations (Iceland, Scotland and Portugal) of the amphipod Echinogammarus marinus were scrutinized. Intersex females from Iceland registered the highest fecundity loss. Only in Scottish samples females with two genital papillae and males with only one genital papillae were observed. Nevertheless, water, biota and sediment samples pointed to equivalent metal levels, and in consonance the prevalence of intersex was not significantly different between locations. An unequivocal relationship between metal presence and intersex induction cannot be presented, but our results advocate the potential role of metals as a direct cause of intersexuality in E. marinus.  相似文献   

5.
Due to their close proximity to the point sources of pollution, estuaries and harbours are exposed to metals. Mussels are used worldwide to monitor marine pollution due to their ability to take up contaminants and the ease of transplantation. Mussels were collected from two reference sites and transplanted in Richards Bay Harbour (2006 and 2010) and in three harbours. Transplanted and resident mussels were removed after 6 weeks exposure and metal concentrations were analysed using ICP-MS techniques. Transplanted mussels had higher metal concentrations than the resident mussels. This was attributed to regulation of metals by the resident mussels. Metal regulation was greater in mussels that are continuously submerged as opposed to those that undergo tidal influences. For monitoring it is essential that the reference population for transplantation is considered carefully as upwelling events in the pristine reference location results in significant increases in metal bioaccumulation.  相似文献   

6.
The oyster Crassostrea rhizophorae is a bivalve abundant in Venezuelan estuaries and consumed by local populations. No known values have been reported on trace metals in oysters from the central Venezuelan coast. We report the concentrations of Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V and Zn in the soft parts of C. rhizophorae, which were collected bimonthly between March 2008 and March 2009, at two sampling areas from the Central Venezuelan Coast: Buche estuary and Mochima estuary. Our results show that for each metal there is a similar temporal variation pattern. The concentrations of the heavy metals reported in this work are useful as reliable baselines and can be used for comparison in future environment studies. Concentrations in C. rhizophorae from the Buche estuary can be interpreted to be high on a global scale for Cd, Cu, Ni and Mn, indicating atypically raised bioavailabilities.  相似文献   

7.
Selenium concentrations have been measured in sediment, fucoid macroalgae and macroinvertebrates from four estuaries of SW England (Yealm, Plym, Looe, Fal). Sediment concentrations ranged from about 0.4 μg g−1 in the Yealm to 1.49 μg g−1 at one site in the Plym. Concentrations in Fucus vesiculosus (0.05–0.31 μg g−1) and F. ceranoides (0.05–0.51 μg g−1) were significantly lower than corresponding concentrations in sediment but there was no correlation between algal and sediment concentrations. Selenium concentrations in Littorina littorea (∼4 μg g−1), Hediste diversicolor (2.82–12.68 μg g−1), Arenicola marina (∼17 μg g−1) and Scrobicularia plana (1.18–6.85 μg g−1) were considerably higher than concentrations in macroalga or sediment, suggesting that Se is effectively accumulated from the diet. Although Se concentrations in some invertebrates exceed toxicity thresholds for the diet of predacious birds and fish, no specific evidence for Se toxicity exists in these estuaries.  相似文献   

8.
In this study of Ukrainian estuaries, sediments and tissues from the Dnieper and Boh estuaries and Danube Delta on the mainland, Sevastopol and Balaklava Bays on the Crimean Peninsula, and coastal Black Sea along the Crimean Peninsula were collected in 2006. Contaminant analyses included several metals, the hydrophobic organic chemicals (HOCs) polychlorinated biphenyls, several chlorinated pesticides, and polycyclic aromatic hydrocarbons. When compared to estuarine sediments globally, the Ukrainian sediments were found to be moderately contaminated. However, several metals, especially mercury, were often shown to be elevated in the tissues of the Ukrainian organisms in comparison to organisms from other estuarine locations. Sediment quality guidelines indicate some of the estuarine sediments could be sufficiently contaminated to cause adverse toxicological effects. This investigation represents the first extensive study of HOC and metal baseline concentrations and distributions in Ukrainian estuaries and seeks to characterize exposures to aquatic organisms living in these systems.  相似文献   

9.
The influence of diet on comparative metal accumulation was investigated using a predatory muricid gastropod Thais clavigera. Individuals were fed for up to 56 days on either barnacles, i.e., Tetraclita squamosa, or mussels, i.e., Perna viridis, collected from metal-contaminated and clean sites. Barnacles and mussels have contrasting metal handling strategies and, therefore, different body concentrations, intracellular distributions and detoxification systems. Field collection of prey items that accumulated body metal concentrations over a lifetime of exposure allowed bioavailability to the predator, T. clavigera, to be assessed naturally, which may not be the case for prey exposed to metals for a short time in the laboratory. T. clavigera that was fed cadmium- and copper-contaminated barnacles or mussels ingested significantly greater amounts compared to those fed conspecifics collected from clean locations. T. clavigera body cadmium and copper concentrations were not, however, significantly different between individuals fed either contaminated or clean prey. Amount of zinc ingested was similar in mussels collected from clean and contaminated environments but much less when compared to the barnacle prey. The body concentrations of zinc in T. clavigera fed mussels collected from both sites fell. In contrast, the amount of zinc ingested from barnacle prey was significantly greater from those collected from the metal-contaminated site as compared to the clean one. This was reflected as significantly greater body zinc concentrations in T. clavigera fed contaminated barnacles compared to those fed clean individuals. Copper and zinc accumulation from prey was, therefore, complex. It varied between metal and between prey type, but appeared to be related to the amount ingested and the metal handling strategy of the prey.  相似文献   

10.
《Marine pollution bulletin》2012,64(5-12):396-401
The concentrations of ten trace metals were determined in the gills, muscles, hepatopancreas, and exoskeleton tissues of Xenograpsus testudinatus that lives around shallow and acidic hydrothermal vents off Kueishan Island, northeastern Taiwan. The analytical results demonstrate that the metal concentrations vary significantly with the type of crab tissue. The concentrations of Al, Cd, Co, Cu, Fe, Ni, and Zn are highest in the gills, whereas the concentration of Mn is highest in the exoskeleton. Cr and Pb concentrations are similar across the different tissues. The enhanced accumulation of most metals in the gills suggests the metal accumulation via the respiration pathway rather than the uptake of food. The results also reveal that the distribution patterns of metals in tissues are similar in the hepatopancreas and muscles, but very different in both the gills and the exoskeleton, perhaps because of the different pathways of metal utilization in the different crab tissues.  相似文献   

11.
In the joint estuary of the Odiel and Tinto rivers (SW Spain), the invasive Spartina densiflora Brongn. and the native Spartina maritima (Curtis) Fernald are growing over sediments with extreme concentrations of heavy metals. The contents of As, Cu, Fe, Mn, Pb and Zn were determined in sediments, rhizosediments and different tissues of both species, from Odiel and Tinto marshes. S. densiflora showed a higher capability to retain metals around their roots and to control the uptake or transport of metals, mediated by a higher formation of plaques of Fe/Mn (hydro) oxides on the roots. At the Tinto marsh, there were no differences between the metal concentrations of the sediment and those of the rhizosediment, a fact that could be explained by the extremely high concentrations of metals which can pass over a threshold value, altering the properties of root cells and preventing roots from acting as a ‘barrier’ to the uptake or transport of metals.  相似文献   

12.
This study investigated the spatial variability of a common faecal indicator organism, Escherichia coli, in an urban salt-wedge estuary in Melbourne, Australia. Data were collected through comprehensive depth profiling in the water column at four sites and included measurements of temperature, salinity, pH, dissolved oxygen, turbidity, and E. coli concentrations. Vertical variability of E. coli was closely related to the salt-wedge dynamics; in the presence of a salt-wedge, there was a significant decrease in E. coli concentrations with depth. Transverse variability was low and was most likely dwarfed by the analytical uncertainties of E. coli measurements. Longitudinal variability was also low, potentially reflecting minimal die-off, settling, and additional inputs entering along the estuary. These results were supported by a simple mixing model that predicted E. coli concentrations based on salinity measurements. Additionally, an assessment of a sentinel monitoring station suggested routine monitoring locations may produce conservative estimates of E. coli concentrations in stratified estuaries.  相似文献   

13.
Spatial and temporal variations of heavy metal contamination in sediments of a small mangrove stand in Hong Kong were examined by laying two transects perpendicular across the shore. Surface sediment samples were taken along the two transects running landward to seaward at intervals of 5 or 10 m during December 1989, and March, July and September 1990. Total concentrations of Cu, Zn, Mn and Pb did not show any specific trend along each transect, although the maximum concentration of heavy metals tended to occur at the landward edge. There was a high level of variability among locations within each transect; for instance, the Cu concentrations fluctuated from 1 to 42 μg g−1. Certain sites contained exceptionally high levels of total metals. Total concentrations of Cu, Zn, Mn and Pb as high as 42, 150, 640 and 650 μg g−1, respectively, were recorded, implying contaminated sediment. A comparison of the two transects indicated that the sediments of Transect B seemed to contain higher total Zn but lower Cu and Mn concentrations than those of Transect A. Most of the heavy metals accumulated in the sediments were not extractable with ammonium acetate and no Cu or Pb was detected in these extracts. The concentrations of extractable Zn and Mn were low, less than 10% of the total metal concentration in the sediment, and appeared to decrease from the landward to seaward samples. For both total and extractable metals, there were significant seasonal fluctuations for both transects, but no specific trends could be identified. These spatial and temporal variations suggest that the scale and representativeness of sampling require careful planning, and a single sample might not give a satisfactory evaluation of the levels of heavy metal contamination in mangrove ecosystems.  相似文献   

14.
ABSTRACT

The seasonal distribution of metals (V, Cr, Co, Cu, Ni, Zn, Pb, Mn, Fe, Al and Ti) in suspended and bottom sediments of four minor estuaries (Terekhol, Chapora, Sal and Talpona rivers) of Goa, India was investigated to understand the metal distribution process in the estuarine region. The highest particulate-metal concentrations were found in low-salinity regions of all the estuaries, in the wet season (e.g. in the Terekhol River, the averages in ppm were Co: 53, Ni: 197, Cu: 208, Zn: 212 and Pb: 65) compared to the dry season averages (Co: 27, Ni: 76, Cu: 105, Zn: 164 and Pb: 13 ppm). The estuarine-mixing diagrams showed non-conservative behaviour in both seasons. The Sal River had the highest particulate-metal concentration (Co: 106, Ni: 300 and Zn: 323 ppm), suggesting an anthropogenic input. The enrichment factor for suspended matter was higher than bottom sediments with extremely high enrichment for Mn (>10). The Geo-accumulation index displayed unpolluted to polluted class for all metals. The study highlights the important role played by small estuaries in seasonal metal release and accumulation along the coastal region.  相似文献   

15.
Brown algae are often used as heavy metal biomonitors and biosorbents because they can accumulate high concentrations of metals. Cation-exchange performed by cell wall polysaccharides is pointed out as the main chemical mechanism for the metal sequestration. Here, we biochemically investigated if the brown alga Padina gymnospora living in a heavy metal contaminated area would modify their polysaccharidic content. We exposed non-living biomass to Cd and Pb and studied the metals adsorption and localization. We found that raw dried polysaccharides, sulfate groups, uronic acids, fucose, mannose, and galactose were significantly higher in contaminated algae compared with the control ones. Metal concentrations adsorbed by non-living biomass were rising comparatively to the tested concentrations. Electron microscopy showed numerous granules in the cell walls and X-ray microanalysis revealed Cd as the main element. We concluded that P. gymnospora overproduces cell wall polysaccharides when exposed to high metal concentrations as a defense mechanism.  相似文献   

16.
Shallow-water hydrothermal activity is widely present at Azores archipelago. Organisms in such environments present great potential as sentinels of the effects derived from chronically exposure to increased temperature, metal concentrations and reduced pH. This study aimed to evaluate metal concentration in Corallina elongata collected at locations exposed and not exposed to shallow-water hydrothermal activity and evaluate changes in its calcareous structure. Elemental concentration was determined and morphometric analysis was performed by scanning electron microscopy. Thicker cell walls and a bleached appearance were observed on C. elongata specimens from the hydrothermally active location, as well as increased concentrations of elements associated to volcanic activity.This study reports on metal accumulation and morphometric changes in the calcareous structure of C. elongata from a hydrothermally active location, adding new data for further research on such habitats and communities, providing an insight on how coralline algae might be affected by ocean acidification.  相似文献   

17.
ABSTRACT

A database of 88 superficial sediment samples, distributed in space and time, was collected from the Sidi Chahed Dam (northeast of Meknes city, Morocco) and from four other reference stations (in the same region) located in supposedly uncontaminated environments. Analyses were focused on the physico-chemical characteristics and concentrations of heavy metals (Fe, Mn, As, Cu, Zn, Pb, Cr, Cd). The database was processed by advanced statistical analysis techniques. The method of classification by self-organizing maps (SOM) was used, permitting understanding and visualization of the spatial and temporal distribution of samples. Principal component analysis (PCA) and SOM hierarchical classification (SOM-HC) were used to validate the classification and detect seasonal variations in heavy metal concentrations. Dependencies between different metal tracers were considered and their spatio-temporal distribution is shown, together with the ranking of clusters, according to their pollution levels. Thus, autumn samples were the only ones with high concentrations of As, compared to the four reference stations. This is due to leaching of bare soil by the first stormy rains of autumn. In winter and spring samples, the concentrations of tracers Mn, Zn, Cu, Pb, Cd and Cr were relatively high compared to those of the reference stations. Summer sample concentrations were most comparable with the reference stations, probably due to the scarcity of rainfall and runoff in this season.
Editor Z.W. Kundzewicz Associate editor E. Gargouri  相似文献   

18.
The suitability of using four bivalve molluscs (Sanguinolaria acuminata, Anadara granosa, Meretrix meretrix, and Pelecyora trigona) in biomonitoring of heavy metals (Cu, Pb, Cd, Zn, and Hg) collected from intertidal regions of the Sunderban mangrove wetland, northeastern part of the Bay of Bengal, were evaluated. Both speciesdependent variability and temporal variations were pronounced. A high degree of organ specificity was evident in the bivalves where gill and mantle exhibited higher metal accumulation due to ion exchange property of the mucous layer covering these organs while shells represent very poor accumulation. Elevated values of Zn and Cu reflect high potential for biomagnification through marine food chain. Metal concentrations in different body size groups of the bivalves do not follow uniform trend. Correlation coefficient between different metal couplings as tested statistically revealed significant coupling for Pb–Zn, Pb–Cu, Zn–Cu, and Hg–Cu. Concentrations of all the metals in specific organs (visceral mass, mantle and gill) of the bivalves exceeded the safe levels according to the international standards for metals compiled by Food and Agricultural Organization of the United Nations and would be of great risk for human consumption. It is concluded that the mussel and clam are suitable biomonitors to employ in programs designed to assess changes in metal pollution in the Sunderban mangrove wetland.  相似文献   

19.
《Marine pollution bulletin》2009,58(6-12):624-631
The Western Scheldt river and estuary is known to be highly polluted as it receives industrial, agricultural and domestic effluents from one of the most populated and industrialised zones in Europe. Aquatic organisms are exposed to pollutants, specifically metals that are present in different environmental phases, e.g. dissolved, suspended material or sediment phases. The objective of this study was to study the relationship that exists between environmental metal levels, the degree of metal uptake by aquatic organisms with the concomitant biological responses. For this purpose the bivalve mollusk, Mytilus edulis, was selected as bioaccumulation indicator organism. Environmental (water and sediment) and mussel samples were collected during the late winter (March 2000) from sampling sites in the Scheldt estuary. Sites were selected to represent a salinity gradient from the mouth of the estuary to the furthest distribution area of mussels upstream in the system. Together with standard water quality parameters (e.g. salinity, dissolved oxygen, dissolved organic carbon, etc.) concentrations of twelve metals were analysed in the water (dissolved and suspended matter) and sediments. Levels of these metals were also measured in the soft tissue of M. edulis, together with concomitant biomarker responses in resident mussel populations at each site. The biomarkers that were included in this study were condition index, scope for growth, survival in air, cell membrane stability, DNA damage, and metallothioneins. Data were subjected to multivariate statistical analysis. The physico-chemical parameters and metals in the environmental samples clustered the sites to reflect the distribution based on the salinity gradient. Bioaccumulation results revealed increased metal uptake along a pollution gradient with the highest metal bioaccumulation occurring at the upstream most sites and therefore closest to the in the industrial activities. However, the biomarker responses clustered the sites in a manner that reflected the influence of combination of internal exposure (bioaccumulation) and external exposure (physico-chemical conditions). These differences in biomarker responses clearly demonstrated were attributed to abiotic factors other than metal pollution alone e.g. localized short-term increases in increased suspended sediment concentrations and decreased dissolved oxygen concentrations.  相似文献   

20.
The amphipod crustacean Talitrus saltator is an established, easily accessible, biomonitor of trace metal bioavailabilities in coastal waters. We have carried out a geographically widespread collection of T. saltator from European shores, stretching from the north-west Atlantic through the Baltic to the Mediterranean. A primary aim of the work was to establish a database of accumulated trace metal concentrations (Cd, Cr, Cu, Fe, Mn and Zn) in this biomonitor. Statistical analysis has shown significant geographical differences in the bioavailabilities of all the metals, the most distinct being copper, iron and manganese. It has proved possible to identify unusually high accumulated concentrations of Cd, Cr, Cu, Fe, Mn and Zn in this biomonitor, indicative of high metal bioavailability at a particular site. These may serve as reference points for future biomonitoring programmes seeking to identify metal contamination in coastal waters.  相似文献   

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