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1.
Restrictions on the use of tributyltin (TBT) in aquaculture and on boats in coastal regions, except for ocean-going vessels, have been in place in Japan since 1990 due to the strong toxic effects of TBT on marine organisms. However, TBT pollution along the Japanese coasts has been reported after this legislation was enacted. In order to elucidate the present status of contamination by butyltin (BT) compounds, we measured the levels of BTs [monobutyltin (MBT), dibutyltin (DBT) and TBT] in seawater and Caprella spp. samples obtained from the western part of Seto Inland Sea, Uwa Sea and Uranouchi Bay in western Japan during March to September, 2001. Butyltins were detected in more than 90% of the seawater samples (n = 59), with average concentrations of 8.2 ± 9.2 (SD) ng MBT L−1, 3.3 ± 3.0 ng DBT L−1 and 9.0 ± 7.0 ng TBT L−1. Among 41 stations situated on coastal lines, a sufficient number of Caprella organisms for chemical analysis could be collected from only 16 stations. The butyltin concentrations in seawater and Caprella samples from Uwa Sea and Uranouchi Bay, in which the dominant industry in both waters is aquaculture, showed significantly higher than or no significant differences from those samples from the western part of Seto Inland Sea, a major heavy-industry area in Japan. As the TBT concentration in seawater increased, the number of Caprella organisms collected decreased. The mean TBT concentration among the seawater samples was above the estimated lowest observable effect concentration (LOEC) that reduces the survival rate of Caprella danilevskii. Thus, the present study indicates that TBT is still a potential ecological hazard to the survival of marine invertebrates inhabiting coasts along western Japan, even 11 years after the partial ban on TBT usage was implemented.  相似文献   

2.
The activities of particulate and soluble phosphatase were analyzed monthly for 1 year in the coastal ecosystems of the NW Mediterranean Sea. The mean contribution of the particulate activity increased from 56% at an MUF-P concentration of 30 μM to 77% at 0.04 μM. This particulate activity was negatively correlated with the DIP, DOP and TDP concentrations when the activities were related to the seawater volume, chlorophyll a or the protein concentration. The TDP correlations were highly significant (p: 0.001). The DOP correlations were significant (p: 0.04) and became highly significant (p: 0.009) at low DIP concentrations (<0.13 μM). The DIP correlations were significant (p: 0.04) only at low DOP concentrations (<0.18 μM). Thus, the effects of seawater DIP and DOP were found to be linked. The soluble activity exhibited distinct phosphatase fractions with high (0.5–29.5 μM) and low (0.02–2 μM) Km values, but none exhibited significant correlations with phosphorus compounds.  相似文献   

3.
REE in the Great Whale River estuary, northwest Quebec   总被引：1，自引：0，他引：1  
We report rare earth element (REE) concentrations of a longitudinal profile within the estuary of the Great Whale River in northwest Quebec and in Hudson Bay. All of the measured REE have concentrations less than those predicted by conservative mixing of seawater and river water, demonstrating removal of the REE from solution. REE removal is rapid, occurring primarily at salinities less than 2‰. Removal of the REE is greatest for the light REE, and ranges from about 7% for the light REE to no more than 40% for the heavy REE. Fe removal is essentially complete at low salinity. The shape of the Fe and REE vs. salinity profiles is not consistent with a simple model of destabilization and coagulation of iron and REE-bearing colloidal material. A linear relationship between the activity of free ion REE3+ and pH is consistent with a simple ion-exchange model for REE removal.Surface and subsurface samples of Hudson Bay seawater are characterized by high REE concentrations and high La/Yb relative to average seawater. The subsurface sample has a Nd concentration of 100 pmol/kg and an εNd of −29.3 ± 0.3. These characteristics are consistent with the high REE concentration, high La/Yb, and low εNd of river inputs into Hudson Bay. These results indicate that rivers draining the Canadian Shield are a major source of non-radiogenic Nd and REE to the Atlantic Ocean. We estimate that outflow of water from Hudson Bay to the Labrador Sea could supply ≈ 30% of the non-radiogenic Nd in North Atlantic Deep Water.  相似文献   

4.
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   

5.
Shallow submarine gas vents in Levante Bay, Vulcano Island (Italy), emit around 3.6t CO2 per day providing a natural laboratory for the study of biogeochemical processes related to seabed CO2 leaks and ocean acidification. The main physico-chemical parameters (T, pH and Eh) were measured at more than 70 stations with 40 seawater samples were collected for chemical analyses. The main gas vent area had high concentrations of dissolved hydrothermal gases, low pH and negative redox values all of which returned to normal seawater values at distances of about 400 m from the main vents. Much of the bay around the vents is corrosive to calcium carbonate; the north shore has a gradient in seawater carbonate chemistry that is well suited to studies of the effects of long-term increases in CO2 levels. This shoreline lacks toxic compounds (such as H2S) and has a gradient in carbonate saturation states.  相似文献   

6.
Detailed studies of the phosphatase activity in the tidelands were examined including the localization of the phosphatase activities and the spatial distributions of the activity in the tidelands around Hiroshima Bay, the Aki-Bingo Open Sea and Isahaya Bay of Kyushu on the western side of Japan. The results indicate that the phosphatase activity of the sediment fraction accounts for 98% of the tideland activity. Furthermore, we classified 19 tidelands into four groups by a cluster analysis using two parameters: phosphatase activities and ATP (adenosine 5(')-triphosphate) biomass. The first group is a member of the tidelands located in areas remote from the cities. They have a low phosphatase activity and low ATP biomass and the seawater in the tideland is very clean. The second is a group with a low phosphatase activity and high ATP biomass. In the tidelands belonging to this group, large numbers of benthos and shellfish can be observed. The third group has a high phosphatase activity and a relatively low ATP biomass. The estuary tidelands located near Hiroshima City belong to the third group. The last one is tidelands with a high phosphatase activity and high ATP biomass. In this group, the ratio of the phosphatase activity to ATP biomass is relatively low. In the summer, we observed deterioration in the water quality and accumulation of sludge on the sea bottom in the tideland of the last group.Moreover, we employed a multiple regression analysis and proposed an equation to obtain the group number of the cluster analysis using the assayed values of the phosphatase activity and the ATP biomass.  相似文献   

7.
The spatial-temporal variations in the amount and biochemical composition of organic matter and the rates of its transformations in the ecosystems of the Russian part of the Sea of Azov are analyzed. Maximum OM concentrations are typical for Taganrog Bay. A characteristic feature of the Sea of Azov is a large proportion of particulate organic matter, which in summer in Taganrog Bay exceeded 35%. It is shown that not only the concentration of organic matter changes from season to season, but also its elementary (Corg, Norg, and Porg) and biochemical composition (proteins, carbohydrates, and lipids). The major biochemical compound of dissolved organic matter is shown to be carbohydrates (13–28%), and that of particulate matter is protein (44–51%). The hydrolytic (phosphatase and protease) and oxidation-reduction enzymes of electron-transport system demonstrate a high activity in summer. The estimated short turnover times of phosphates and protein suggest the rapid and complete utilization of organic matter in the Sea of Azov.  相似文献   

8.
Shells of the pod razor shell (Ensis siliqua) from 13 locations around the west coast of mainland Britain have been analysed by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for a range of trace metals including Zn, Cd, Pb, U, Ba, Sr and Mg. The trace metal record in these shells is a proxy record for changes in seawater chemistry during the 1990s. Regional variations exist in the median concentrations of the analysed metals. Barium concentrations are related to increased productivity from sewage sludge dumping at sea. Strontium shows a local relationship to salinity, but there is no clear relationship over the study area, instead high Sr is often associated with high Ba, and may reflect ontogenetic factors such as growth rate. Magnesium shows a seasonal variation within individual shells and can be used to calculate sea surface temperatures from groups of shells. Contaminant metals show a clear regional relationship with known sources, thus high Pb and Zn are typically associated with former metal mining areas (e.g. Cardigan Bay, Anglesey), and high Pb, Zn, Cd and U are associated with industrial activity in Liverpool Bay. Anomalies such as the high U in shells from northern Scotland cannot at present be explained. A seasonal variation of Pb is also seen in Cardigan Bay and Liverpool Bay, relating to increased winter fluxes of these metals to the marine environment. The regional distribution of these metals is consistent with known sources of contamination and patterns of seawater migration around the coast of Britain.  相似文献   

9.
Intertidal animals and sediment from Kachemak Bay, Alaska were analysed to determine the concentrations of hydrocarbons. At Coal Point the herbivorous limpet Collisella pelta contained petroleum within its tissues while intertidal algae of the area have previously been shown to accumulate petroleum as a surface coating. At Coal Bay, a locality where both petroleum and coal are present, the filter feeding mussel Mytilus edulis contained petroleum hydrocarbons whereas the deposit feeding clam Macoma balthica contained an array of hydrocarbons suggesting detrital coal as the source. Animals higher in the food web including the gastropod Nucella lima and the urchin Strongylocentrotus droebachiensis showed no evidence of petroleum. All samples contained biogenic hydrocarbons of algal and planktonic origin.  相似文献   

10.
The skeletal banding observed in vertical cross-sections of two species of coral,Montastrea annularis from Jamaica andDiploria labrynthiformis from Bermuda, has been confirmed to be annual by ingrowth of228Th towards radioactive equilibrium with228Ra taken up from seawater. In addition the Bermuda coral is shown to have incorporated210Pb at essentially constant specific activity over at least the last thirty years.The individual annual patterns of growth banding in a suite of specimens ofD. Labrynthiformis from Bermuda are shown to be correlative. The mass of CaCO3 accumulated each year is positively correlated with the band width for the corresponding year.  相似文献   

11.
The effects of exposure to seawater dispersions of northern crude oils on the locomotory activity of two Arctic marine invertebrates, the amphipod Onisimus affinis and the coelenterate Halitholus cirrattus have been examined. Low concentrations of the oils significantly impair activity in both species. The ecological implications of such sublethal effects may be important.  相似文献   

12.
Caffeine in Boston Harbor seawater   总被引：1，自引：0，他引：1  
Caffeine has been detected in Boston Harbor seawater with concentrations ranging from 140 to 1600 ng l(-1), and in Massachusetts Bay seawater at concentrations from 5.2 to 71 ng l(-1). Sources of caffeine appear to be anthropogenic with higher concentrations in the seawater of Boston's inner harbor and in freshwater sources to the harbor. Charles River water and Deer Island sewage treatment plant effluent, the two major sources of freshwater to the harbor, contained 370 and 6700 ng l(-1) of caffeine, respectively, in 1998. Sewage influent and effluent concentrations appear to be consistent with consumption estimates of caffeinated beverages for the Boston area and total organic carbon removal targets for treated sewage. Caffeine was inversely correlated to salinity in a transect from the mouth of Boston Harbor to Stellwagen Basin, indicating it may be a useful chemical tracer of anthropogenic inputs to marine systems.  相似文献   

13.
Well-preserved metalliferous sediments and pillow basalts of Lower Ordovician age (ca. 490 Ma) have been studied in an attempt to specify the Nd isotopic composition of Iapetus seawater. Initial143Nd/144Nd ratios of the pillow basalts are indistinguishable from published initial ratios for the 505-Ma Bay of Islands ophiolite complex and are within the anticipated range for MORB-type basalts 500 Ma ago. Metalliferous sediments occur both interstitial to basalt pillows and as well-developed sedimentary accumulations. The initial143Nd/144Nd ratios for the non-interstitial variety range from 0.511851 to 0.511712 (εNd = ?2.7to?5.4) and are considered to provide an estimate of143Nd/144Nd in Iapetus seawater. The interstitial metalliferous sediments show evidence for a significant basalt-derived Nd component. Although volcanic activity occurred at the margin of Iapetus essentially contemporaneous with the formation of the metalliferous sediments, it is clear that arc-type volcanic material was not a major source of Nd in Iapetus seawater. Rather the source of Nd was from continental regions with a similar average age to those supplying material to the present-day Atlantic Ocean.  相似文献   

14.
Samples of water, sediment and mussels (Mytilus edulis) from the southern Baltic Sea have been analysed for total hydrocarbons by fluorescence spectroscopy and capillary gas chromatography. The sediment and mussel samples have also been analysed for specific aliphatic and aromatic hydrocarbons by computerized capillary gas chromatography-mass spectrometry. The highest hydrocarbon concentrations in all samples occurred either inshore (particularly in Gdansk Bay) or in deep offshore basins where fine sediment accumulates.  相似文献   

15.
The shallow-water hydrothermal system in Tutum Bay on the west side of Ambitle Island, Papua New Guinea provides us with an exceptional opportunity to study isotope systematics in a near shore setting. Compared to seawater, the hydrothermal fluids in Tutum Bay have lower values for δD, δ18O, δ13C, and 87Sr and higher values for 3H, δ34S(SO4) and δ18O(SO4). The δ18O and δD records for vents 1 and 4 indicate that fluid compositions remained stable over an extended period. Interpretation of isotope data clearly demonstrates the predominantly meteoric origin of Tutum Bay hydrothermal fluids, despite their location in a marine environment. δ18O and δD values are identical to mean average annual precipitation in eastern Papua New Guinea. The hypothesis that these fluids are a simple product of mixing between seawater and onshore hydrothermal fluids from the Waramung (W-1) and Kapkai (W-2) thermal areas has been rejected, because the observed δ37Cl, 3H, δ34S(SO4) and δ18O(SO4) values cannot be explained by a simple mixing model. The application of δ18O(SO4) and δ13C thermometers in combination with 3H values corroborates the three-step model of Pichler et al. [Pichler, T., Veizer, J., Hall, G.E.M., 1999. The chemical composition of shallow-water hydrothermal fluids in Tutum Bay, Ambitle Island, Papua New Guinea and their effect on ambient seawater. Marine Chemistry 64 (3) 229–252], where (1) phase separation in the deep reservoir beneath Ambitle Island produces a high temperature vapor that rises upward and subsequently reacts with cooler ground water to form a low pH, CO2-rich water of approximately 150–160 °C, (2) caused by the steep topography, this CO2-rich fluid moves laterally towards the margin of the hydrothermal system where it mixes with the marginal upflow of the deep reservoir fluid. This produces a dilute chloride water of approximately 165 °C, and (3) possibly the entrainment of minor amounts of ground or seawater during its final ascent.  相似文献   

16.
《Marine pollution bulletin》1999,38(11):1005-1010
Studies of butyltin compounds in soil, benthic sediments and the Asian clam Potamocorbula amurensis were conducted at the former Mare Island Naval Shipyard, and nearby Mare Island and Carquinez Straits in San Francisco Bay, California. Soils from a sandblast abrasives dump site at the shipyard contained low concentrations of mono-, di- and tributyltin (0.3–52 ng/g, total butyltin). Similarly, concentrations of total butyltin in benthic sediments from nearby Mare Island and Carquinez Straits ranged from 1.3 to 8.1 ng/g. In contrast, clams accumulated much greater concentrations (152–307 ng/g, total butyltin). Tributyltin (TBT) and dibutyltin (DBT) made up from 54–85% to 15–46%, respectively, of the total butyltin body burden of the clams. Biota Sediment Accumulation Factors (BSAFs) for butyltins in Potamocorbula were in reasonable agreement with literature values; they are greater than those of neutral hydrophobic compounds, suggesting that partitioning and binding processes may be involved in bioaccumulation. Tributyltin is a potent endocrine disrupting chemical. There is potential for long-term chronic effects of TBT in San Francisco Bay.  相似文献   

17.
In this study, we report results concerning the accumulation of heavy metals in seawater from Izmit Bay. The bay was divided into the three parts: the eastern, the central and the western basins. The goal of this study was to determine levels of heavy metals at various depths in the bay between April 2008 and May 2010. Liquid–liquid extractions were performed on seawater samples. An atomic absorption spectrophotometer was used to measure levels of six metals: lead, cadmium, chromium, iron, manganese and zinc. We applied our results to evaluate the status of pollution in the Gulf of Izmit. Significant seasonal differences in metal concentrations and higher concentrations of many metals in water near the shore are evidence for uncontrolled release of pollutants in the water.  相似文献   

18.
The concentrations of 129I in seawater samples from two sites (off Sekine and the Toyama Bay) in the Japan Sea were determined by accelerator mass spectrometry. The observed concentrations exceed amounts expected from natural origin and globally distributed fallout due to nuclear weapons testing. Because the fraction of natural origin and global fallout is 2% and 8.9–13.8%, respectively, the residual more than 80% of the concentration must come primarily from nuclear fuel reprocessing plants. This result indicates a rapid distribution of 129I through atmospheric transport on a global scale. The depth distribution of 129I at the Toyama Bay in the Japan Sea shows that the 129I maximum is in the mixed layer and that concentrations decrease with depth. The inventory of 129I in water column is four times higher than that measured in the Gulf of Mexico which has almost the same depth at the Toyama Bay. This higher inventory probably reflects: (1) the rapid water sinking in the Japan Sea, (2) the difference of distance in sampling locations with respect to major 129I releasing plants and (3) the strong increase in emissions from nuclear fuel reprocessing plants after the profile of the Gulf of Mexico was taken.  相似文献   

19.
Seventeen whole-rock samples, generally taken at 25–50 m intervals from 5 to 560 m sub-basement in Hole 504B, drilled in 6.2 m.y. old crust, were analysed for87Sr/86Sr ratios, Sr and Rb concentrations, and18O/16O ratios. Sr isotope ratios for 8 samples from the upper 260 m of the hole range from 0.70287 to 0.70377, with a mean of 0.70320. In the 330–560 m interval, 5 samples have a restricted range of 0.70255–0.70279, with a mean of 0.70266, the average value for fresh mid-ocean ridge basalts (MORB). In the 260–330 m interval, approximately intermediate Sr isotopic ratios are found.δ18O values (‰) range from 6.4 to 7.8 in the upper 260 m, 6.2–6.4 in the 270–320 m interval, and 5.8–6.2 in the 320–560 m interval. The values in the upper 260 m are typical for basalts which have undergone low-temperature seawater alteration, whereas the values for the 320–560 m interval correspond to MORB which have experienced essentially no oxygen isotopic alteration.The higher87Sr/86Sr and18O/16O ratios in the upper part of the hole can be interpreted as the result of a greater overall water/rock ratio in the upper part of the Hole 504B crust than in the lower part. Interaction of basalt with seawater(87Sr/86Sr=0.7091) increased basalt87Sr/86Sr ratios and produced smectitic alteration products which raised whole-rock δ18O values. Seawater circulation in the lower basalts may have been partly restricted by the greater number of relatively impermeable massive lava flows below about 230 m sub-basement. These flows may have helped to seal off lower basalts from through-flowing seawater.  相似文献   

20.
Organotin compounds (OTs) have caused widespread adverse effects on marine organisms. As no local restrictions on OT-based antifouling paints have been implemented in China, high concentrations of OTs still occur in coastal environments. In this study, we measured the imposex status and tissue concentrations of OTs in the whelk Reishia clavigera collected along the coast of Dapeng Bay and Daya Bay of Shenzhen, China in 2013. Our results showed that all female whelks suffered from the onset of imposex. The highest concentration of total OTs was 27,756 μg kg−1 dry weight in the samples collected from Shuitousha. Triphenyltin was the most predominant residue, accounting for more than 97.8% of total OTs across all sites. Compared with the results from previous studies, the marine environment of this region is still heavily contaminated with OTs. Therefore, a tightened control is necessary to regulate the use and release of OTs in China.  相似文献   

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