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底栖生物是海洋环境质量的重要指标。2016年夏季对舟山近岸海域37个站位的底栖生物进行调查，此次调查共鉴定出底栖生物45种，平均栖息密度为41 ind/m2，平均生物量为3.92 g/m2，底栖生物的栖息密度和生物量基本上由西向东逐渐升高。底栖生物的种类、密度、生物量、多样性指数与水深及水质中的盐度、pH、悬浮物、总磷、总氮呈弱或中等程度相关，与沉积物中重金属（铜、锌、铅、镉、铬、总汞）、砷、有机碳呈弱或中等程度的相关性，尤其与镉含量的相关性最为明显。由ABC曲线分析可知，该调查海域底栖生物受到一定程度的扰动。与2005年该海域调查结果比较表明，该海域底栖生物的多样性指数平均值较2005年略有降低，平均生物量较2005年降低，但平均密度较2005年升高。此次调查出现无底栖生物站位所占的比例较2005年上升。研究表明，2016年舟山海域海洋环境质量状况劣于2005年，应加强海洋环境监测与治理。 相似文献
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In this study the biotransference of selenium copper, cadmium, zinc, arsenic and lead was measured in a contaminated seagrass ecosystem in Lake Macquarie, NSW, Australia, to determine if biomagnification of these trace metals is occurring and if they reach concentrations that pose a threat to the resident organisms or human consumers. Selenium was found to biomagnify, exceeding maximum permitted concentrations for human consumption within carnivorous fish tissue, the highest trophic level examined. Selenium concentrations measured within carnivorous fish were also above those shown to elicit sub-lethal effects in freshwater fish. As comparisons are made to selenium concentrations known to effect freshwater fish, inferences must be made with caution. There was no evidence of copper, cadmium, zinc or lead biomagnification within the food web examined. Copper, cadmium, zinc and lead concentrations were below concentrations shown to elicit adverse responses in biota. Copper concentrations within crustaceans M. bennettae and P. palagicus were found to exceed maximum permitted concentrations for human consumption. It is likely that copper concentrations within these species were accumulated due to the essential nature of this trace metal for many species of molluscs and crustaceans. Arsenic showed some evidence of biomagnification. Total arsenic concentrations are similar to those found in other uncontaminated marine ecosystems, thus arsenic concentrations are unlikely to cause adverse effects to aquatic organisms. Inorganic arsenic concentrations are below maximum permitted concentrations for human consumption. 相似文献
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James G. Sanders 《Marine environmental research》1980,3(4):257-266
The arsenic cycle in productive, near-shore marine systems is complex, involving both geochemical inputs and outflows and biological mediation. The major input to the Georgia Bight is intrusion of subsurface Gulf Stream water; in other marine systems, river run-off and atmospheric deposition may provide a large percentage of the arsenic input. Indiscriminate biological uptake is responsible for changes in arsenic speciation, involving approximately 20% of the dissolved arsenate pool and resulting in measurable concentrations of reduced and methylated arsenic species. The overall cycle is similar to the phosphate cycle; however, regeneration time for arsenic is much slower. 相似文献
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Nicolai Mirlean Paulo Baisch Marcelo P. Travassos Cristina Nassar 《Geo-Marine Letters》2011,31(1):65-73
Arsenic levels (up to 130 mg kg−1) substantially exceeding the official threshold have recently been documented in beach and nearshore sediments along more
than 50 km of coastline in the Brazilian state of Espírito Santo between 19°50′ and 20°12′S. In an attempt to assess the sources
of this enrichment, we performed a study on arsenic distribution in the main mineral substances and living organisms in the
beach environment. Laboratory tests on arsenic retention by beach carbonate debris have also been carried out. The data suggest
that sedimentary arsenic occurs largely bound to particles of the calcareous red alga Corallina panizzoi, whereby live specimens contained much smaller amounts of this metalloid than was the case for nonliving material (2.4 and
20.3 mg kg−1, respectively). Experimental tests confirmed the ability of C. panizzoi detritus to retain arsenic at pH intervals and ionic strength characteristic of seawater. There are two potential sources
of that metalloid for calcareous debris in sediments: brown macroalgae, which were found to contain high levels of As (up
to 66.3 mg kg−1), and ferruginized sandstones (up to 23.0 mg kg−1). We argue that any contribution of brown algae to beach sediment enrichment by As would be minor, and consider the ferrous
sandstones from coastal sedimentary rocks of the Barreiras Group as the principal large-scale source of arsenic in the marine
environment of Espírito Santo. The experimental data, together with field studies, corroborate the interpretation that arsenic
anomalies in sediments with calcareous debris can form when weathered continental rocks even only slightly enriched in As
are leached by marine waters, and the As is at least partially retained by biogenic calcareous detritus in nearshore sediments.
Considering that rocks of the Barreiras Group are exposed to marine erosion far to the north of Espírito Santo, we estimate
that marine sediments containing calcareous material are “anomalously” enriched in As along approximately 2,000 km of the
Brazilian tropical coastline. 相似文献
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The chemical forms and distribution of dissolved arsenic species in the estuary of the River Beaulieu (Hampshire, U.K.) are reported. ‘Inorganic arsenic (V)’ in both the marine and riverine estuary inputs are in true solution, passing through ultrafiltration membranes having a nominal molecular weight cut-off of 500 daltons. Extensive removal of dissolved ‘inorganic arsenic (V)’ is apparent from the distribution of arsenic in the estuary, with laboratory mixing experiments indicating that removal is favoured in the low salinity region. ‘Inorganic arsenic (III)’ and methylated arsenic species account for up to 41% and 70% of the dissolved arsenic, respectively, but are only found during the warmer months when water temperatures exceed ca. 12°C. 相似文献
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In this study, 36 fish species were collected from three coastal cities in Korea to investigate levels and patterns of six arsenicals (arsenite: As (III), arsenate: As (V), arsenocholine: AsC, arsenobetaine: AsB, monomethylarsonic acid: MMA, and dimethylarsinic acid: DMA). The levels of ∑6 As in the different fish species varied substantially, ranging from 0.02 μg As/g ww (Islaeli carp) to 9.65 μg As/g ww (Skate ray) with a median of 0.40 μg As/g ww. All the arsenicals in marine fishes showed higher levels than those in freshwater fishes due to fish feed living in saline water. Overall, marine carnivorous fishes seem to be more contaminated with arsenic. For all the fish samples, AsB (mean fraction: 90.6%) was dominant among the six arsenicals, indicating biomethylation of inorganic arsenic and accumulation of AsB. Fish species with high water contents showed elevated levels of As (III), but there was no further significant correlations between arsenicals and water/lipid contents. Concentrations of As (V) were significantly lower than those of As (III), which implies that As (V) is reduced during biomethylation of inorganic arsenic. Consequently, we hypothesize that the toxicity of arsenic (mainly derived from As (III)) can be increased by the reduction of As (V), especially for the fish species with higher water contents. 相似文献
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Replicate portions of a Delaware salt marsh were enclosed in cylindrical microcosms and exposed to elevated levels of inorganic arsenic (arsenate). All biotic and abiotic components in dosed cylinders rapidly incorporated arsenic. Spartina blades showed the greatest arsenic enrichment, with dosed plants incorporating arsenic concentrations an order of magnitude higher than controls. Spartina detritus and sediments also exhibited greatly elevated arsenic concentrations. Virtually all of the arsenic was incorporated into plant tissue or strongly sorbed to cell surfaces. Thus, elevated arsenic concentrations in estuarine waters will be reflected in living and non-living components of a salt marsh ecosystem, implying that increased arsenic will be available to organisms within the marsh ecosystem. 相似文献
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Anita E Geiszinger Walter Goessler Kevin A Francesconi 《Marine environmental research》2002,53(1):37-50
Arsenic compounds in the marine polychaete Arenicola marina collected from Odense Fjord, Denmark were determined by HPLC-ICPMS. In contrast to most other marine animals, A. marina contained most of its water soluble arsenic as inorganic forms, arsenite (58%) and arsenate (16%), and arsenobetaine was present as a minor constituent (6%) only. Other arsenic compounds detected in A. marina were dimethylarsinate (4%), two arsenosugars (1 and 3%), tetramethylarsonium ion (1.5%), and arsenocholine (<1%). A new arsenobetaine -trimethylarsoniopropionate-previously only reported in fish, was also present at trace levels (<1%), and an unknown anionic arsenical (approximately 10%) remains unidentified. When A. marina was exposed in laboratory experiments to different concentrations of arsenate in seawater (10, 50. 100, 500 and 1000 microg As 1(-1)) the polychaetes accumulated arsenic in a dose dependent. non-linear manner. Most of the accumulated arsenic was biotransformed to arsenite and dimethylarsinate. with the remainder being accumulated as unchanged arsenate. None of the other arsenic compounds naturally present in A. marina increased in concentration following arsenate exposure. 相似文献
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福建闽南沿海养殖贝类体中砷含量的分布 总被引：9，自引：0，他引：9
通过2003~2004年对福建闽南沿海5种养殖贝类体砷含量的调查监测,对养殖贝类体中砷含量的分布进行了探讨.福建闽南沿海5种养殖贝类体总砷含量为0.65×10-6~4.80×10-6,总平均值为2.09×10-6,其中有机砷和无机砷占总砷含量的百分比分别为61.6%~98.2%和2.3%~38.4%,平均值分别为88.8%和11.2%.在相同养殖区,养殖贝类体总砷平均含量的种间分布差异较小.滩涂养殖底栖贝类体内总砷平均含量总体上高于浅海筏式养殖贝类体的平均含量.福建闽南沿海5种养殖贝类体内总砷含量在泉州湾、湄州湾、东山湾和九龙江口高,在诏安湾和围头湾低,在其余各湾相近.5种养殖贝类体内无机砷的污染指数和总平均值分别为0.05~0.76和0.23,总砷的污染指数和总平均值分别为0.06~0.48和0.21,总体符合国家食品卫生质量标准.养殖贝类体中砷含量与体长之间总体成正相关. 相似文献
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With the rising cost of oil the electric power generating companies are turning to coal as a fuel source. Large amounts of fly ash are produced as a by product of coal combustion. This fly ash must then be disposed of, with the oceans being considered an alternative to land fill disposal. This research investigated the sorptive behavior of the surface-associated arsenic and utilized the results to project arsenic's impact on the water column during the ocean disposal of fly ash.Several acid digests were investigated to determine an effective method of arsenic recovery from fly ash. Of these, the HCl digest was the most effective technique, yielding 100% arsenic recoveries from fly-ash particles. The arsenic content of the fly ashes studied varied from 69 ± 11 μg g−1 to 323 ± 24 μg g−1, reflecting differences in the arsenic content of the source coal. In both seawater and freshwater there is an increase in arsenic desorption with increasing pH. The greatest release of arsenic occurred at pH 12 with generally over 80% of the surface arsenic released.Fly ash in contact with seawater and freshwater can exhibit either acidic or alkaline tendencies depending upon the soluble elemental composition on the surface of the flyash particle. The acidic ashes were shown to leach a greater percentage of arsenic (16.9%) than the more alkaline ashes (8.2%). During these leaching studies in seawater, arsenic was found to leach in both the pentavalent and trivalent oxidation state. The pentavalent state was predominant, comprising 77% of the arsenic initially desorbed.The dissolution in seawater of arsenic was utilized to assess the possible impact of the ocean disposal of fly ash. Based upon these data it appears that the natural levels of arsenic in the water column would not be significantly increased. Further research is needed on the fate of fly-ash particles in marine sediments. 相似文献
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This study assessed whether trace elements present at Deception Island, an active submarine volcano in the Antarctic Peninsula, show enhanced biological availability to the local marine community. Using a weak acid extraction method to dissolve organic material and leach associated but not constitutive trace elements of sediments, fifteen elements were measured from seafloor sediment, seawater particulates, and tissues of benthic (bivalves, brittlestars, sea urchins) and pelagic (demersal and pelagic fishes, krill) organisms collected in the flooded caldera. The highest element concentrations were associated with seafloor sediment, the lowest with seawater particulates and organism tissues. In the case of Ag and Se, concentrations were highest in organism tissue, indicating contamination through the food chain and biomagnification of those elements. The elements Al, Fe, Mn, Sr, Ti, and to a lesser extent Zn, were the most concentrated of the trace elements for all sample types. This indicates that the whole ecosystem of Deception Island is contaminated with trace elements from local geothermal activity, which is also reflected in the pattern of element contamination in organisms. Accordingly, element concentrations were higher in organisms collected at Deception Island compared to those from the neighboring non-active volcanic King George Island, suggesting that volcanic activity enhances bioavailability of trace elements to marine organisms. Trace element concentrations were highest in digestive tissue of organisms, suggesting that elements at Deception Island are incorporated into the marine food web mainly through a dietary route. 相似文献
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Total arsenic, arsenate and arsenite concentration profiles for the water column of Saanich Inlet, an intermittently anoxic fjord located on Vancouver Island, B.C., Canada, were measured using independent analytical techniques for total arsenic and arsenic speciation to evaluate the accuracy of the speciation technique in both oxic and anoxic marine environments. Total arsenic profiles indicate a mid-depth minimum of about 1.0 ppb above the oxic—anoxic interface and an enrichment in the anoxic zone to about 2.0 ppb. This minimum may be due to either advection of arsenic-poor water into Saanich Inlet at mid-depth or arsenic incorporation onto solid phases within a bacteria- and manganese-rich particulate layer located immediately above the oxic—anoxic interface and subsequent removal via sinking particulate material. Ratios of total arsenic to phosphorus in the deep, anoxic waters of the basin are similar to those reported for marine algae, suggesting that the enrichment of total arsenic within the anoxic bottom layer may be due to its release upon organic matter decomposition.Arsenate and arsenite concentration versus depth profiles indicate a rapid (but incomplete in a thermodynamic sense) response to the oxic—anoxic interface. The arsenate/ arsenite concentration ratio is 15/1 in the oxic region of the water column and 1/12 in the anoxic zone. Arsenate—arsenite interconversion occurs at a depth shallower than ferric-ferrous but deeper than MnO2 —Mn2+ interconversions.Measurements of arsenite oxidation rates at near-ambient arsenite concentrations and temperatures using an 74As3+ radioactive tracer technique indicate that arsenite oxidation is initially ten times faster in seawater taken from the manganese-rich particulate layer at 165 m depth than in seawater collected near the surface at 50 m depth. Addition of antibiotics to seawater from 165 m depth initially suppressed the rate of arsenite oxidation, indicating that it may be partially microbially mediated. 相似文献
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于1987年和1988年春、秋两季分析测定了胶州湾24种经济生物体内的重金属铜、铅、镉、锌和铬含量。结果表明,受周围污染环境的影响,该湾经济生物体内的锌、铬、铅和铜含量明显高于受排污影响较小的黄海中部海域同种生物体内的含量;不同种类、体长和不同季节生物体内的重金属含量都有较显著差异。本调查还采用在湾内广泛分布且游动能力差的菲律宾蛤仔探讨了不同地点生物体内重金属含量,未发现潮下带蛤仔与距污染源远近有明显关系。鉴于该湾生物体内重金属含量均低于“海洋生物污染评价标准”和“人体消费标准”,可以认为,胶州湾经济生物体的可食部分对人类食用还是安全的。 相似文献
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海洋活性多肽的研究进展 总被引：17，自引：0，他引：17
根据海洋活性多肽是近年来新药研究热点的现状 ,本文对天然存在的海洋活性多肽和海洋蛋白酶解活性肽的研究进展进行了综述。为进一步开展海洋活性多肽的研究提供参考。 相似文献
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《African Journal of Marine Science》2013,35(3):449-464
The SEAChange programme, instituted in 2007 under the auspices of the South African Network for Coastal and Oceanic Research (SANCOR), included four interdependent research themes, one of which was Marine Biotechnology. Marine biotechnology is a discipline that involves both basic and applied research, and is aimed at the commercial exploitation of marine organisms. This paper reviews the progress made in three key areas of the SEAChange programme over the first five years, namely marine aquaculture, omics of marine organisms and marine bioprospecting, and discusses these accomplishments in context to marine biotechnology internationally. 相似文献
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为减少重金属污染和保护海洋生态环境,文章基于2014年10月博贺湾海域的调查数据,分析海水和生物的重金属污染情况,并采用内梅罗指数和目标危险系数评价海水质量和人类食用海产品而摄入重金属的潜在健康风险。研究结果表明:博贺湾海域海水重金属含量总体较低,大部分符合一类海水水质标准;Pb的空间分布不均匀,高值区主要分布于莲头岭附近站位,很有可能是受港口区和产业园区排污的影响;水质等级为较清洁和清洁,海水重金属污染的整体程度较低;生物重金属含量大部分符合一类海洋生物质量标准,生物质量总体较高,其中软体类的重金属含量整体较高且Pb和Cd含量较高,鱼类的重金属含量整体较低但Hg含量较高,所有生物的Cu和Zn含量均较高;各生物重金属污染的目标危险系数均小于1,人类食用生物样品的海产品而摄入重金属没有潜在健康风险。 相似文献