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1.
《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
2.
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
3.
《Marine pollution bulletin》2014,81(1-2):263-274
The current study aimed to examine the relationship between metals in sediments and metal bioaccumulation in oyster tissue in a highly-modified estuary (Sydney estuary, Australia). While extensive metal contamination was observed in surficial sediments, suspended particulate matter and oyster tissue, a significant relationship between these media could not be established. No relationship was determined between sediment quality guidelines and oyster size or weight, nor with human consumption levels for metals in oyster tissue. Moreover, oyster tissue metal concentrations varied greatly at a single locality over temporal scales of years. Oyster tissue at all 19 study sites exceeded consumptions levels for Cu. Bioaccumulation of metals in oyster tissue is a useful dynamic indicator of anthropogenic influence within estuaries, however oysters cannot be used in Sydney estuary as a valid biomonitor due to overriding internal regulation (homoestasis) by the animal, or by external natural (sediment resuspension) and anthropogenic (sewer/stormwater discharges) pressures, or both. 相似文献
4.
《Marine pollution bulletin》2009,58(6-12):790-800
The artificial mussel (AM), a novel chemical sampling device, has been developed for monitoring dissolved trace metals in marine environments. The AM consists of Chelex-100 suspended in artificial seawater within Perspex tubing and enclosed with semi-permeable polyacrylamide gel at both ends. To validate the field performance of the AM in temperate waters, we deployed AMs alongside transplanted blue mussels Mytilus edulis in coastal environments in Scotland (Holy Loch, Loch Fyne, Loch Striven and Millport) and Iceland (Reykjavikurhöfn, Gufunes, South of þerney, Hofsvik, Hvalfjörður and Sandgerði) for monitoring trace metals. While uptake patterns of Cd between the AM and M. edulis were highly comparable, discrepancies were found in the accumulation profiles of the other metals (Cu, Cr, Pb and Zn), in particular Zn. Nonetheless, the AMs gave a better resolution to accurately reveal the spatial difference in dissolved metal contamination when compared with M. edulis. AMs complement the use of mussels since AMs indicate dissolved metals in seawater, whereas uptake by mussels indicates a mixture of dissolved and particulate metals. Our results also indicated that historical metal exposure of the transplanted M. edulis could significantly confound their metal concentrations especially when the deployment period was short (i.e. <34 d). This study suggested that the AM can overcome problems associated with variable biological attributes and pre-exposure history in the mussel, and provides a standardized and representative time-integrated estimate of dissolved metal concentrations in different marine environments. 相似文献
5.
Desorption and bioaccumulation of Cd, Zn, and Pb were studied using naturally contaminated sediment from a brackish water pond in the Sunderban Biosphere Reserve in India. Pattern of desorption of the metals from the sediment and bioaccumulation in fingerlings of the teleost Oreochromis mossambicusand postlarvae of the shrimp Penaeus monodon were studied as a function of salinity and loading of detritus of a mangrove plant. Effects of both salinity and loading of detritus on bioaccumulation of the metals were studied under two conditions: either the animals were allowed free access to the sediment or access was denied. Ninety‐six hour experiments showed that desorption of Cd and Pb from sediment into water increased with salinity of the medium while desorption of Zn decreased. Salinity of the medium also had a significant effect on the bioaccumulation of metals by fish; Cd and Pb accumulation decreased in saline medium while the accumulation of Zn increased. Conditions of access to sediment had no effect on the bioaccumulation of metals by fish; effect of interaction between salinity and access condition was also insignificant. The access conditions, however, significantly influenced accumulation of metal by the shrimp postlarvae. The effect of interaction between salinity and access condition was insignificant in influencing the bioaccumulation of all metals except Zn. The accumulation of Zn increased as a function of the salinity of the medium when shrimp postlarvae were allowed access to the sediment. Desorption of metals from sediment to water were below detection limits when detritus of a mangrove plant was added to the medium. Both the level of detritus and the conditions of access influenced accumulation of metals by fish, but the effect of interaction between the two factors were found to be insignificant. Shrimp postlarvae showed net accumulation only of Pb in the presence of detritus and the accumulation of Pb increased when the larvae were separated from the sediment. The results are important in understanding the mobility of metals between solid and aqueous phases in brackish water environments that experience periodic fluctuations in salinity and fluxes of organic load in the form of mangrove detritus. 相似文献
6.
T. Baussant R.K. Bechmann I.C. Taban B.K. Larsen A.H. Tandberg A. Bjørnstad S. Torgrimsen A. Nævdal K.B. Øysæd G. Jonsson S. Sanni 《Marine pollution bulletin》2009,58(12):1796-1807
Mytilus edulis and Chlamys islandica were exposed to nominal dispersed crude oil concentrations in the range 0.015–0.25 mg/l for one month. Five biomarkers (enzymatic and cellular responses) were analysed together with bioaccumulation of PAHs at the end of exposure. In both species, PAH tissue residues reflected the exposure concentration measured in the water and lipophylicity determined the bioaccumulation levels. Oil caused biomarker responses in both species but more significant alterations in exposed C. islandica were observed. The relationships between exposure levels and enzymatic responses were apparently complex. The integrated biomarker response related against the exposure levels was U-shaped in both species and no correlation with total PAH body burden was found. For the monitoring of chronic offshore discharges, dose- and time-related events should be evaluated in the selection of biomarkers to apply. From this study, cellular damages appear more fitted than enzymatic responses, transient and more complex to interpret. 相似文献
7.
The artificial mussel (AM), a novel chemical sampling device, has been developed for monitoring dissolved trace metals in marine environments. The AM consists of Chelex-100 suspended in artificial seawater within Perspex tubing and enclosed with semi-permeable polyacrylamide gel at both ends. To validate the field performance of the AM in temperate waters, we deployed AMs alongside transplanted blue mussels Mytilus edulis in coastal environments in Scotland (Holy Loch, Loch Fyne, Loch Striven and Millport) and Iceland (Reykjavikurh?fn, Gufunes, South of thornerney, Hofsvik, Hvalfj?rethur and Sandgerethi) for monitoring trace metals. While uptake patterns of Cd between the AM and M. edulis were highly comparable, discrepancies were found in the accumulation profiles of the other metals (Cu, Cr, Pb and Zn), in particular Zn. Nonetheless, the AMs gave a better resolution to accurately reveal the spatial difference in dissolved metal contamination when compared with M. edulis. AMs complement the use of mussels since AMs indicate dissolved metals in seawater, whereas uptake by mussels indicates a mixture of dissolved and particulate metals. Our results also indicated that historical metal exposure of the transplanted M. edulis could significantly confound their metal concentrations especially when the deployment period was short (i.e. <34d). This study suggested that the AM can overcome problems associated with variable biological attributes and pre-exposure history in the mussel, and provides a standardized and representative time-integrated estimate of dissolved metal concentrations in different marine environments. 相似文献
8.
Studies into the partitioning of trace metals between the dissolved phase and suspended solids have been performed on two major UK estuaries, the Mersey and the Humber. Aqueous phase trace metal concentrations were determined, along with partitioning data (Kp) determined from both laboratory equilibration experiments and by chemical leaching techniques.
Dissolved trace metals in the Humber essentially exhibited conservative behaviour (or a slight positive deviation). In the Mersey, however, removal of zinc, chromium, and, in particular, copper and cadmium occurred in the low salinity region.
Sequential extraction data gave an indication of the nature of trace metal bindings to suspended sediment, and revealed total extractable trace metals on the Mersey suspended sediment to be a factor of two greater than that found in the Humber. Similarly, partition coefficients in the Mersey were approximately an order of magnitude greater than in the Humber. Chloro-complexation was shown to control the partitioning of cadmium within estuaries. Copper, however, exhibited a distinct trend of increasing Kp with increasing salinity. 相似文献
9.
Nutrient Dynamics and Productivity in Three European Estuaries 总被引：3，自引：0，他引：3
The Scheldt, Gironde and Sado estuaries exhibit quite different characteristics regarding the annual river discharges, nutrient loads and oxygen conditions. Distribution patterns of nutrients, dissolved oxygen, suspended matter and chlorophyll a as well as the nutrient ratios and half saturation constants, allow the identification and comparison of specific processes. The Scheldt emerges as the most eutrophic estuary being, in general, not nutrient limited and functions as a source of phosphorus and nitrogen. Intense biogeochemical processes take place in this system. The Sado is shown to be a moderately productive system, the upper part being enriched in nutrients and chlorophyll a and showing a tendency for oxygen depletion in summer. Different factors seem to control phytoplankton production along the salinity gradient: light regime landwards and nitrogen seawards. By contrast, the Gironde does not show clearly the presence of sinks or sources regarding nutrients and exhibits a reduced productivity essentially controlled by turbidity. The high amounts of particles seem also to be responsible for localized processes such as phosphate sorption/desorption and silicate regeneration. 相似文献
10.
Philip S. Rainbow 《Marine pollution bulletin》1995,31(4-12)
Biomonitors can be used to establish geographical and/or temporal variations in the bioavailabilities of heavy metals in the marine environment, offering time-integrated measures of those portions of the total ambient metal load that are of direct ecotoxicological relevance. Heavy metal biomonitors need to conform to certain required characteristics, not least being metal accumulators. Use of a suite of biomonitors allows recognition of the presence and relative magnitude of different metal sources. For example, a macrophytic alga responds essentially to dissolved metal sources only, a suspension feeder like a mussel responds to metal sources in dissolved and suspended phases, and a deposit feeder responds to metal available in the sediment. Examples are given of suitable heavy metal biomonitors in the coastal waters of Europe, New Zealand, Hong Kong and China. It is not valid to compare absolute accumulated metal concentrations in biomonitors interspecifically, although interspecific comparisions of rank orders do allow cross correlations of relative bioavailabilities of heavy metals to different biomonitors at the same sites. There is a need to identify widespread cosmopolitan biomonitors to allow intra-specific comparisons of bioavailabilities between geographical areas. Such cosmopolitan biomonitors may include the alga Ulva lactuca, mussels of the genera Mytilus and Perna, the oysters Ostrea and Crassostrea, barnacles like Balanus amphitrite and Tetraclita squamosa, and the talitrid amphipod Platorchestia platensis. A major caveat in the use of such cosmopolitan biomonitors remains the need for reliable, specific taxonomic identification. 相似文献
11.
Concentrations of dissolved metals (Cd, Cu, Ni, Mn and Zn) were determined for summer and winter, under low-flow conditions in Port Jackson, a microtidal, well-mixed estuary in south-east Australia. Mean concentrations of Cd (0.04+/-0.02 microg/l), Ni (0.86+/-0.40 microg/l), Mn (20.0+/-25 microg/l) and Zn (6.47+/-2.0 microg/l) were below water quality guidelines. Concentrations of Cu (1.68+/-0.37 microg/l), however, slightly exceeded recommended values. Dissolved Ni and Mn behaved mostly conservatively, whereas Cd, Cu and Zn showed mid-estuarine maxima. Peaks in Cd, Cu and Zn concentrations were located in the upper estuary, independent of the salinity and suspended particulate matter loading, and were consistent with anthropogenic inputs of metals in the estuary. Concentrations of dissolved Cu were highest in summer, whereas concentrations of Cd, Ni and Mn were significantly lower in summer than winter (P< or =0.05). The increase in temperature and biological activity during summer explained the seasonal variation. The sequence of log K(d) values (20-30 salinity) was Mn>Zn>Cu>Ni. These results give unique information concerning the contemporaneous distribution of dissolved trace metals in the Port Jackson estuary and they provide a data set against which the long-term contamination may be assessed. 相似文献
12.
A. Gmez-Parra J. M. Forja T. A. DelValls I. Senz I. Riba 《Marine pollution bulletin》2000,40(12):1115-1123
The Guadalquivir estuary was impacted by the accidental release of 5 million cubic meters of acid waste from the processing of pyrite ore (25 April 1998). The waste entered ecologically sensitive and protected areas such as the National Park of Doñana. Here are presented the results obtained from a time sequence of different sampling sites in the estuary and in the surrounding areas from May to September 1998. Water, suspended solids and sediments were analysed for six different metals (Fe, Mn, Zn, Cd, Pb, Cu). Also, the concentration of the metals in the different geochemical sediment fractions was determined as a means of assessing bioavailability. The results obtained during the first weeks after the incident show high concentrations of Zn. At the end of June a 10 000 m3 temporary water-treatment plant was constructed on site for depuration of the toxic waters. The results obtained in August and September show a decrease in the metal concentrations measured in the estuary. Only concentrations of Zn were higher than sediment quality values proposed by various authors. 相似文献
13.
The aim of this study was to evaluate the usefulness of oxidative stress biomarkers of pollution in native mussels Mytilus edulis chilensis from the Beagle Channel. Spatial and seasonal variations of catalase, glutathione-S-transferase and lipid peroxidation in gills and digestive gland were analyzed in relation to environmental parameters, heavy metals in sediment and in tissue. Four sites with anthropogenic impact and a control site were selected and monitored during the four seasons of 2007. We found significant differences among sites in concentrations of dissolved nutrients and heavy metals in sediments, with the highest values recorded at sites with anthropogenic pressure. Different patterns were observed between concentrations of metals in tissues and in sediments suggesting differences in bioavailability. There were also significant differences in biomarker responses among sites, despite the strong seasonal variability. Our results showed relatively moderate levels of pollution in the study area as a result of urban influences. 相似文献
14.
To simulate the behavior of radionuclides along a salinity gradient, in vitro sorption and desorption kinetics of Co, Mn, Cs, Fe, Ag, Zn and Cd were studied in Loire river water and the macrotidal Loire estuarine water over two different seasons. Partitioning between the dissolved phase and suspended solids were followed up over 100 h after adding radioactive tracers to freshly collected freshwater (sorption stage); this stage was followed by desorption in fresh and estuarine waters. A kinetic model describing the interactions between trace metals and particles under a salinity gradient was developed and calibrated. Among parameters and/or processes that control the fate and behavior of contaminated particles during their transfer in estuarine systems, this study shows that the speciation of trace metals is controlled by: (i) the chemical water composition: for all the elements except for Fe, desorption increased with salinity; however, the amplitude of such an effect strongly depended on the element and/or on the composition of the particulate phase (and consequently on the season); (ii) the possibility for a given element to form (or not) stable surface particle moieties such as oxides or inner-sphere complexes; (iii) the distribution of a given element among different types of sites characterised by different binding forces that can lead (or not) to re-adsorption processes after mixing of contaminated particles with uncontaminated water.Our model enabled the quantification of the contribution and the characteristic time of reactions that took place over short and long periods on the global partitioning between particulate and dissolved phases during sorption and desorption and to determine the extent to which these reactions were modified by the salinity. 相似文献
15.
In order to study the impact of produced water (PW) from a North Sea oil field on blue mussels (Mytilus edulis), chemical and biological markers were selected. A laboratory exposure (0.125%, 0.25% and 0.5% of PW) and a field study (6 stations 0.2-2 km from a PW discharge point) were conducted. In the laboratory study, PAH bioaccumulation increased in mussel soft tissue even at the lowest exposure dose. Micronuclei frequency demonstrated a dose-response pattern, whereas lysosomal membrane stability showed tendency towards a dose-response pattern. The same markers were assessed in the field study, biomarker analyses were consistent with the contamination level, as evaluated by mussel polycyclic aromatic hydrocarbons body burden. Overall, obtained results confirmed the value of an ecotoxicological approach for a scientifically sound characterisation of biological effects induced by offshore oilfield operational discharges. 相似文献
16.
Nutrient and suspended sediment concentrations were measured in the dry season and during the rising and falling stages of flood events in the Annan and Daintree rivers to estimate catchment exports. These flood events were also sampled along the salinity gradient in the estuary and nearshore shelf to quantify the modification of terrestrial sediment and nutrient loads as they pass through estuaries into the Great Barrier Reef lagoon. In the Daintree River TSS concentrations were found to increase between the catchment and the estuary plume. The source of TSS may have been scour of the estuarine channel or from land use in the catchment of the lower estuary. In the dry season nitrogen enters the Annan and Daintree estuaries predominantly in the form of PON and DON in roughly equal proportions. Nitrogen exports to the GBR are mostly in the form of DON. In the wet season the majority of nitrogen enters the estuaries as DON and leaves as PON. Nitrogen removal in the estuaries and plumes appears to be biologically mediated once suspended sediment concentrations decrease to a point where phytoplankton growth is not light limited. In the dry season phosphorus enters and leaves the estuaries primarily in organic form. PIP is the dominant form of phosphorus in river water, but leaves the estuary more evenly distributed between all forms. These estuarine processes result in less nitrogen and phosphorus being delivered to the GBR lagoon than is exported from the catchment. The differences between these estuaries highlights the need for further work to explore modifications in estuaries that drain into the Great Barrier Reef lagoon. 相似文献
17.
Motivated by field studies of the Ems estuary which show longitudinal gradients in bottom sediment concentration as high as O(0.01 kg/m4), we develop an analytical model for estuarine residual circulation based on currents from salinity gradients, turbidity gradients, and freshwater discharge. Salinity is assumed to be vertically well mixed, while the vertical concentration profile is assumed to result from a balance between a constant settling velocity and turbulent diffusive flux. Width and depth of the model estuary are held constant. Model results show that turbidity gradients enhance tidally averaged circulation upstream of the estuarine turbidity maximum (ETM), but significantly reduce residual circulation downstream, where salinity and turbidity gradients oppose each other. We apply the condition of morphodynamic equilibrium (vanishing sediment transport) and develop an analytical solution for the position of the turbidity maximum and the distribution of suspended sediment concentration (SSC) along a longitudinal axis. A sensitivity study shows great variability in the longitudinal distribution of suspended sediment with the applied salinity gradient and six model parameters: settling velocity, vertical mixing, horizontal dispersion, total sediment supply, fresh water flow, and water depth. Increasing depth and settling velocity move the ETM upstream, while increasing freshwater discharge and vertical mixing move the ETM downstream. Moreover, the longitudinal distribution of SSC is inherently asymmetric around the ETM, and depends on spatial variations in the residual current structure and the vertical profile of SSC. 相似文献
18.
Surface waters collected along the salinity gradient of the Hudson River estuary in four cruises between 1995 and 1997 were size-fractionated into particulate (>0.45 μm), ‘dissolved' (<0.45 μm), colloidal (10 kDa, 0.45 μm) and low molecular weight (<10 kDa) phases. Dissolved Cd concentrations (range: 0.11–1.19 nM) in surface waters of the estuary appear to have decreased fourfold (from an average of 2.36 to 0.61 nM) over a 23-year period, since the initial analysis of samples collected in the 1970s by Klinkhammer and Bender [Estuar. Coastal Shelf Sci. 12 (1981) 629–643]. This interannual decline reflects improvement in sewage treatment and the elimination of industrial Cd sources to the Hudson River estuary. In contrast, dissolved Mn levels (range: 0.033–1.46 μM) have remained relatively constant over the same period of time, suggesting that anthropogenic sources have very limited impact on Mn concentrations in the estuary. The concentrations of both Cd and Mn appeared to strongly depend on the season and/or river discharge. The highest concentrations were detected under low freshwater discharge, implying that limited hydraulic flushing allows a build-up of metals in the water column. Although the decline in Cd levels within the estuary reflects a reduction in the magnitude of anthropogenic inputs, mass balance estimates indicated that current sources of Cd to the estuary include sewage discharges (in the lower estuary around Manhattan) and diagenetic remobilization from industrial Cd deposited in sediments nearly 2 decades ago (in the upper estuary near Foundry Cove). Moreover, under low river discharge, the sources considered in our model (sewage, riverine input, atmospheric deposition, and benthic fluxes) could account for no more than 60% of the Cd exported from the lower estuary to the ocean. This suggests that undefined sources such as ground water and inputs from other watersheds (e.g., Long Island Sound and Newark Bay) may potentially influence the water quality of the New York Harbor. The size-fractionated metal concentrations indicated that most of the traditionally defined ‘dissolved' Cd and Mn consisted of <10 kDa molecular weight species. High molecular weight colloidal species of Mn accounted for about 50% of the dissolved fraction at the riverine end-member and <5% at intermediate and high salinities. Colloidal Cd accounted for <6% of the dissolved phase throughout the estuary. Unlike the non-conservative excess (relative to ideal dilution of river water and seawater) of dissolved Mn observed along the estuary, high molecular weight colloidal Mn appeared to be removed at the head of the estuary. The small contribution of colloidal Cd and Mn to the ‘dissolved' phase suggests that remobilization from suspended particulate phases and/or from sediments occurs through the formation of small molecular weight species. 相似文献
19.
The use of bivalves such as the brown mussel (Perna perna) and the black mussel (Choromytilus meridionalis) is common in the study of marine pollution and the effect of these pollutants on ecosystems and are important in both economic and ecological roles. Namibian marine ecosystems are threatened by pollution from mining, commercial fishing and population growth. The aims of this study were to determine baseline metal concentrations, spatial variation and variation between species. Metal levels in C. meridionalis from Guano Platform (GP) are the lowest of all the sites. The most polluted sites are Rocky Point (RP), Halifax Island (HIL) and between Walvis Bay and Swakopmund (WS). The bioaccumulation of metals between P. perna and C. meridionalis were not uniform for all metals. Overall the study indicates the condition of the coastline to be mostly normal, with Cd and Pb levels being of concern. 相似文献
20.
Fucus ceranoides tolerates abiotic conditions encountered across the full range of estuarine salinities. We examined the bioaccumulation of metals in individuals and metal concentrations in accompanying sediment samples collected at different locations along estuaries of South West England. Intra- and inter-estuarine variations in metal accumulation by F. ceranoides, after correction for particulate contamination using Fe as a proxy, were attributed to variations in the availabilities and concentrations of aqueous metals. Greatest accumulation was observed in estuaries that remain most heavily impacted by historical mining activities and for metals that were mobilised to the greatest extent during these operations (As, Cu, Sn, Zn). Arsenic concentrations displayed a seaward increase in estuaries in which multiple samples were taken, whereas Cd concentrations were always greatest in samples collected from the most landward locations. Ongoing research aims to better understand the mechanisms and kinetics of metal interactions with F. ceranoides and their dependence on salinity. 相似文献