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1.
《Marine pollution bulletin》2014,78(1-2):325-332
Ratios of sucrose-negative to sucrose-positive vibrios on TCBS agar (suc−/suc+) indicate the abundance of potential human pathogenic non-cholera vibrios in coastal mariculture environments of the Lingayen Gulf (Philippines. In guts of adult maricultured milkfish (Chanos chanos) of suc− vibrios reached extreme peak values ranging between 2 and 545 million per g wet weight. Suc− vibrios outnumbered suc+ vibrios in anoxic sediments, too, and were rarely predominant in coastal waters or in oxidized sediments. Suc−/suc+ ratios in sediments increased toward the mariculture areas with distance from the open sea at decreasing redox potentials. There is circumstantial evidence that suc− vibrios can be dispersed from mariculture areas to adjacent environments including coral reefs. An immediate human health risk by pathogenic Vibrio species is discounted, since milkfish guts contained mainly members of the Enterovibrio group. A representative isolate of these contained proteolytic and other virulence factors, but no genes encoding toxins characteristic of clinical Vibrio species.  相似文献   

2.
Colonial auk (Alcid) populations can be used as indicators of the effects of oil pollution on the seabirds of Canada's coastal zones. Of approximately 11 million breeding colonial alcids in Canada and in adjacent West Greenland waters, 87% are murres. Common Eiders may serve as the best indicators of the effects of oil pollution in Canada's western Arctic where colonial alcids are scarce.  相似文献   

3.
In the marine environment, vibrios adhere to a number of substrates including chitin-rich organisms such as crustaceans. Their wide diffusion in coastal waters and pathogenic potential require knowledge of the lifestyle and environmental reservoirs of these bacteria. To test the presence of culturable vibrios in coastal areas and their association with benthic crustaceans, vibrios were isolated from water, sediments and crustaceans (copepods and anphipods) at three stations placed in front of heavily used tourist beaches of the Adriatic Sea. We observed significant correlations between vibrios and temperature. Benthic and planktonic copepods harboured vibrios in summer, while benthic amphipods harboured these bacteria in spring and autumn. Vibrio alginolyticus and Vibrio parahaemolyticus strains gave positive results using primers for Vibrio cholerae toxR and toxS. Sedimentary crustaceans may extend Vibrio persistence in seawater and may represent an additional aquatic reservoir of these bacteria.  相似文献   

4.
Water levels and flows in the Singapore coastal waters are driven by the complex interactions of the Indian and Pacific Ocean tides, seasonal monsoon-driven contributions and also forced by local winds. The Singapore Regional Model was developed to simulate hydrodynamics in the Strait of Singapore which produces representative sea level variation in this region. However, resolution and alignment of the grid system of the model with respect to depth contours in some of its subregions, i.e., the Johor Estuary area require further improvement. For this, the grid system of the model was modified and compared the simulated results with field measurements. The computed flow velocities agreed better with field observations when the grid resolution was increased. However, improving the alignment of the grid with the channel boundary (with a much lower increase in grid resolution) provided a substantially larger improvement of the model performance. The grid modification greatly influenced the computed salinity in the estuary, while water levels are slightly affected. Further analysis of model results showed a pronounced ebb tidal asymmetry generated by the O1–K1–M2 tidal constituents in the estuary.  相似文献   

5.
Radiocaesium, introduced into coastal waters in the effluent from the B.N.F.L. nuclear fuel reprocessing plant at Windscale, is present at significant levels throughout the Clyde Sea Area. Concentrations reached maximum in April, 1977, and have recently declined. Around 30% of Windscale radiocaesium output passes through the Clyde Sea Area but less than 0.3% remains in sediments. There appears to be no major radiological safety hazard. The radiocaesium is, however, an excellent tracer species for both waters and sediments. The Irish Sea-derived component comprises over 90% of Clyde seawater and may well introduce major inventories of pollutants. The average water residence time in the Clyde system is 4.5 months, although significantly longer entrainment is evident in northern sea lochs. Study of radiocaesium variations has enabled improved assessment of the Clyde's response to marine pollution.  相似文献   

6.
The status report on metal pollution in tropical estuaries and coastal waters is important to understand potential environmental health hazards. Detailed baseline measurements were made on physicochemical parameters (pH, temperature, redox potential, electrical conductivity, salinity, dissolved oxygen, total dissolved solid), major ions (Na, Ca, Mg, K, HCO3, Cl, SO4 and NO3) and metals concentrations (27Al, 75As, 138Ba, 9Be, 111Cd, 59Co, 63Cu, 52Cr, 57Fe, 55Mn, 60Ni, 208Pb, 80Se, 66Zn) at estuaries and coastal waters along the Straits of Malacca. Principal component analysis (PCA) was employed to reveal potential pollution sources. Seven principal components were extracted with relation to pollution contribution from minerals-related parameters, natural and anthropogenic sources. The output from this study will generate a profound understanding on the metal pollution status and pollution risk of the estuaries and coastal system.  相似文献   

7.
Currents, coastal winds, coastal sea level, and coastal ocean temperatures were observed at a number of northern Baja California Pacific sites between October 1978 and October 1979. Coastal winds were weakly southward on average and fluctuated north-south throughout the year. Fluctuations were uncorrelated over alongshore separations of 200 km. Coastal winds differed considerably from the large-scale offshore wind estimate (Bakun's Index) both in strength and in variability. At 30°50′N the mean currents were weakly equatorward at 25 m depth and weakly poleward at 42 and 60 m in a water depth of 75 m. The seasonal mean flow was equatorward from October to April and poleward from April to October at the shallower level but poleward all year near bottom. The fluctuations on a time scale of days to weeks were about an order of magnitude stronger than the seasonal variation, were oriented predominantly alongshore, and were quasi-barotropic in nature. Empirical orthogonal analyses showed that almost 90% of the variability could be represented by a single empirical mode. The alongshore fluctuations were significantly correlated with coastal sea level from October to July but during the rest of the year correlation was insignificant, possibly as a result of offshore eddies approaching the shelf.Observations at 25- and 60-m depth at a second mooring 100 km south of the first indicated a mean alongshore divergence from April to July 1979, consistent with long-term mean geostrophic flow patterns for the area. In general, currents were correlated alongshore but a two-week event in May, which manifested itself differently at the two sites, was suggestive of the impingement of an eddy onto the continental shelf. Currents and winds were poorly correlated in general.Temperature variation at sites along 700 km of coast showed a strong seasonal variation with the winter cool period extended by spring upwelling. Days-to-weeks scale fluctuations were similar at the five northernmost sites and correlations alongshore were significant for separations of up to 400 km. No evidence of propagating events was found in coastal temperatures or in currents.  相似文献   

8.
The use of antifouling paints to the boats and ships is one among the threats facing coastal resources including coral reefs in recent decades. This study reports the current contamination status of diuron and its behaviour in the coastal waters of Malaysia. The maximum concentration of diuron was 285 ng/L detected at Johor port. All samples from Redang and Bidong coral reef islands were contaminated with diuron. Temporal variation showed relatively high concentrations but no significant difference (P > 0.05) during November and January (North-East monsoon) in Klang ports (North, South and West), while higher levels of diuron were detected during April, 2012 (Inter monsoon) in Kemaman, and Johor port. Although no site has shown concentration above maximum permissible concentration (430 ng/L) as restricted by the Dutch Authorities, however, long term exposure studies for environmental relevance levels of diuron around coastal areas should be given a priority in the future.  相似文献   

9.
Sources of pollution discharges and water quality samples at 27 stations in 2006 in the coastal waters of Hebei Province, western Bohai Sea, have been analyzed in this study. Pollutant loads from industrial sewages have shown stronger impact on the water environment than those from the general sewages. Analysis indicates that pollution of COD is mainly resulted from land-based point pollutant sources. For phosphate concentration, non-point source pollution from coastal ocean (fishing and harbor areas) plays an important role. To assess the water quality conditions, Organic Pollution Index and Eutrophication Index have been used to quantify the level of water pollution and eutrophication conditions. Results show that pollution was much heavier in the dry season than flood season in 2006. Based on COD and phosphate concentrations, results show that waters near Shahe River, Douhe River, Yanghe River, and Luanhe River were heavily polluted. Water quality in the Qinhuangdao area was better than those in the Tangshan and Cangzhou areas.  相似文献   

10.
A brief analysis of the current situation pertaining to marine pollution prevention and management in the East Asian Seas is outlined, particularly focusing on pollution arising from both land and sea-based sources. This paper highlights the results of a Regional Programme supported by the Global Environment Facility (GEF) in addressing some of the key marine pollution management problems of the region. The Programme has made significant progress in the following areas: (a) successfully developed and tested working models on the application of integrated coastal management (ICM) in addressing land-based sources of pollution; (b) tested risk assessment and risk management methodologies for addressing pollution in the Straits of Malacca; (c) attained commendable records in the ratification of marine pollution-related conventions; (d) developed an operational modality for stronger public and private sector partnerships; (e) demonstrated the cost-effectiveness of marine pollution monitoring programs; (f) focused on capacity building at the local level, and (g) with the above achievements, it has illustrated a paradigm shift in concept, approach and methodology in addressing the mounting environmental pressure caused by increasing marine pollution loads.  相似文献   

11.
The Sulitjelma Gabbro situated at 67.2°N, 15.4°E was intruded close to the Late Ordovician climax of regional metamorphism in the northern Scandinavian Caledonides. Magnetic properties have been examined from samples collected at seven localities in the south western part of this body. Total NRM directions show a tendency to be aligned near the present earth's magnetic field direction in this region. Stability to a.f. demagnetisation is low and commensurate with low Koenigsberger ratios (0.001–0.16) and the presence of unoxidised magnetite as the principal remanence carrier. After cleaning the site mean directions no longer show an alignment near the present earth's field and of six statistically significant sites three are approximately reversed with respect to remainder. The combined mean direction after cleaning isD = 195°,I = 15° (precision parameterk = 6) and the derived virtual geomagnetic pole is at 0°E, 14°S (α95 = 23°). This pole is close to poles of comparable age from the British Isles and suggests that Britain and Norway were part of the same crustal plate in Ordovician times. Discrepancies between Siluro-Devonian results from the two regions may be due to inadequate age coverage of present results.  相似文献   

12.
In 2011, northern fulmars (Fulmarus glacialis) from Iceland were used to test the hypothesis that plastic debris decreases at northern latitudes in the Atlantic when moving away from major human centres of coastal and marine activities. Stomach analyses of Icelandic fulmars confirm that plastic pollution levels in the North Atlantic tend to decrease towards higher latitudes. Levels of pollution thus appear to link to regions of intense human coastal and marine activities, suggesting substantial current inputs in those areas.  相似文献   

13.
The extent of the effect of technogenic sources in the Baikal Natural Territory on Lake Baikal water area and coastal zone is assessed. Regional pollution from sources remote from the lake migrates over tens of kilometers in accordance with wind rose and transforms into local in the water protection zone of Lake Baikal. Snow pollution in lake water area has been recorded near the coastal populated localities Listvyanka, Kultuk, Baikal’sk, Slyudyanka, Ust’-Barguzin, Severobaikal’sk, Nizhneangarsk, and at Selenga R. mouth and found to have a local character. The southern depression ranks first in terms of the input of NO2, NO3, NH4, PO4, F, Al, Na, Ba, Mo, Mn, Pb, Cu, Zn, Sr, Hg, and oil products onto lake water area through the atmosphere. However, larger amounts of SO4, H2CO3, Cl, Ca, Mg, and K falls onto the northern depression, and more Be, V, Cr, and Co falls onto the middle part, because of the operation of coastal enterprises, boiler-houses, TPPs, stove heating, motor-car emissions, and natural transport of dust in low-snow areas. Data on the past 15 years show the pollution to drop by half in the late 1990s and early 2000s because of industrial decline. However, a small increase in regional pollution by individual components could be seen in the recent 5 years.  相似文献   

14.
Due to increasing development Southeast Asia’s coastlines are undergoing massive changes, but the associated impacts on marine habitats are poorly known. Singapore, a densely populated island city–state, is a quintessential example of coastal modification that has resulted in the (hitherto undocumented) loss of seagrass. We reconstructed the historic extent and diversity of local seagrass meadows through herbarium records and backwards extrapolation from contemporary seagrass locations. We also determined the current status of seagrass meadows using long-term monitoring data and identified the main threats to their presence in Singapore. Results show that, even though ∼45% of seagrass has been lost during the last five decades, species diversity remains stable. The main cause of seagrass loss was, and continues to be, land reclamation. We conclude that strict controls on terrestrial runoff and pollution have made it possible for seagrass to persist adjacent to this highly urbanised city–state.  相似文献   

15.
The characteristic magnetization of redbed samples from the upper part of the Série d'Abadla (probably Early Permian 31°N, 2.7°W) has a mean direction derived from 13 sites of D=129°, I=11°, k=59, α95=6° and a corresponding south paleopole at 29°S, 60°E, A95=5°. All directions have reversed polarity. The paleolatitude of the northern fringe of the Saharan craton was 6°±3°S, which is in excellent agreement with that for the Moroccan Meseta. Therefore, in all probability, there has been no paleolatitudinal displacement greater than about 500 km of the Moroccan Meseta relative to Africa since Permian time. Comparison of results from sedimentary rocks shows no evidence for relative rotation of the Moroccan Meseta since Permian time. Small apparent rotations are indicated by evidence from massive trachyandesite lavas from Morocco, but we argue that these could have arisen from the incomplete averaging of secular variation and uncertainties in estimates of paleohorizontal, rather than from true tectonic rotations. The combined latest Carboniferous/Early Permian paleopole for the Saharan craton and the Meseta differs form the path of apparent polar wandering for North America when the continents are assembled in Wegener's Pangea (Pangea A, in which northwest Africa is opposite North America). It is in reasonable agreement when the continents are assembled in the Pangea B configuration (northwest Africa opposite Europe).  相似文献   

16.
The Straits of Malacca is subjected to a great variety of environmental stresses due to its strategic location as a major international shipping lane and the concentration of agriculture, industry and urbanisation which predominate on the west coast of Peninsular Malaysia. This paper gives an overview of the study conducted in the Malacca Straits as part of the GEF/UNDP/IMO Regional Programme on the Prevention and Management of Marine Pollution in the East Asian Seas, in particular pertaining to the identification of land and sea-based sources of pollution in Malaysia which contributes to the pollution load in the Straits, as well as the assessment of the relative contribution of each source.  相似文献   

17.
The pollution mechanisms affecting the protected wetland of the river Evros delta, were investigated during an one year survey (1992–1993). The eastern part of the wetland was mainly influenced by river transported pollution which is generated in the greater catchment basin of the river Evros, in Bulgaria, Turkey and Greece. In this part of the wetland, the highest concentrations of organic matter were found during summer, but nutrients concentrations increased during the early winter months. Nitrogen concentrations remained high throughout spring but SRP concentrations decreased considerably during the same period. In the western part of the wetland, the watercourses were mainly influenced by local activities (agriculture and animal breeding) but pollutant concentrations were lower than in the river stations. These preliminary results indicate that river transported pollution is the major factor for the quality degradation of the wetland's waters.  相似文献   

18.
To understand the coastal water quality of San Andrès Island, and provide tools for the management of its marine resources, we present the historical analysis of the island monitoring, which includes ammonia, nitrites, nitrate, phosphates, fecal and total coliforms. The anthropogenic pressure on the coastal system is heavy, with water nutrification, posing at risk seagrass and coral ecosystems. During dry season, biologically available nitrogen is 3-9 times higher than the maximum recommended for coral reefs, while during wet season values are 2-6.4 times the maximum. Biologically available phosphorous is also high, 1-8 times the maximum during dry season, 2-13 times during wet season. In some sites the concentration of pathogenic bacteria is above the limits set by law for primary and secondary contact. It is urgent to improve the management of sewage discharge, the main polluting source of San Andres coastal waters.  相似文献   

19.
Cluster analysis (CA), discriminant analysis (DA) and principal component analysis (PCA) were comprehensively coupled to explore and identify the spatial and temporal variation and potential pollution sources in coastal water quality along Macau peninsula. The results show that the 12 months could be grouped into two periods, June–September and the remaining months, and the entire area divided into two clusters, one located at the western sides, and the other on the southeast and southern sides of the Macau peninsula. Through backward stepwise DA, pH, Cl−, TSS, Color and TP, Chloride, Color, NH4 +, DO, COD were discriminant variables of spatial and temporal variation, with 84.82 and 76.54% correct assignments, respectively. Fecal pollution, organic pollution and soil weathering are among the major sources for coastal water quality deterioration along Macau peninsula. This study illustrates that application of multivariate statistical techniques was beneficial to gain knowledge for further optimizing the monitoring network and controlling coastal water quality along Macau peninsula.  相似文献   

20.
Traditional and molecular methods (PCR) were used to detect, quantify and identify the source of fecal pollution in coastal sites of Puerto Rico and Trinidad. Enterococci and Escherichia coli standard plate counts were used as a general indicator of fecal contamination while the PCR detection of Bifidobacteria adolescentis and human or bovine specific Bacteroidales were used to examine potential sources. Seven of 14 sites in Trinidad including Maracas Bay which is a major public beach contained significant fecal contamination based on enterococci numbers counts exceeding established thresholds for areas of direct contact. Forty six percent of the 27 stations in Puerto Rico were over the established thresholds for enterococci and 49% according to E. coli counts. About 31% of the stations examined in Puerto Rico had evidence of human derived fecal contamination. Human fecal pollution was detected in only one station from Trinidad. Bovine derived contamination was detected only once.  相似文献   

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