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1.
In a survey in Greece from 1987 to 2000 hepatotoxic cyanobacterial blooms were observed in 9 out of 33 freshwaters. Microcystins (MCYSTs) were detected by HPLC in 7 of these lakes, and the total MCYST concentration per scum dry weight ranged from 50.3 to 1638 ± 464 μg g—1. Cyanobacterial genera (Microcystis, Anabaena, Anabaenopsis, Aphanizomenon, Cylindrospermopsis) with known toxin producing taxa were present in 31 freshwaters. From our data and a review of the literature, it would appear that Mediterranean countries are more likely 1) to have toxic cyanobacterial blooms consisting of Microcystis spp. and 2) to have higher intracellular MCYST concentrations. A case study in Lake Kastoria is used to highlight seasonal patterns of cyanobacterial and MCYST‐LR occurrence and to assess cyanotoxin risk. Cyanobacterial biovolume was high (> 11 μL L—1) throughout the year and was in excess of Guidance Level 2 (10 μL L—1) proposed by WHO for recreational waters and Alert Level 2 for drinking water. Further, surface water samples from April to November exceeded Guidance Level 3, with the potential for acute cyanobacterial poisoning. Intracellular MCYST‐LR concentrations (max 3186 μg L—1) exceeded the WHO guideline for drinking water (1 μg L—1) from September to November with a high risk of adverse health effects. Preliminary evidence indicates that in 3 lakes microcystins are accumulated in some aquatic organisms. Generally, a high risk level can be deduced from the data for the Mediterranean region.  相似文献   

2.
This study reports the analysis of polycyclic aromatic compound (PAC) metabolites, as biomarkers of exposure to PACs in marine environment. PAC metabolites were measured in bile samples from 14 species of demersal fish caught in the São Sebastião Channel (SSC), SE Brazilian coastline. Naphthalene (NPH) equivalents, phenanthrene (PHN) equivalents, and benzo[a]pyrene (BaP) equivalents were quantified using a reverse-phase high-performance liquid chromatography coupled with fluorescence detection method. For all samples, the means (±standard deviation, n = 37) of concentrations obtained for NPH, PHN, and BaP equivalents were, respectively, 290,000 ± 200,000 ng/g, 18,000 ± 14,000 ng/g, and 970 ± 1900 ng/g. These results indicate recent exposure of these fish to PACs in their environment. In addition, two species (Cyclichthys spinosus and Prionotus nudigula) of fish were analyzed in order to investigate local sources of PAC contamination in the SSC and the influence of the petroleum terminal in fish caught in remote areas. The results showed that these fish species potentially migrate along the channel, especially P. nudigula. Correlations among groups of PAC metabolites indicate the same petrogenic source for NPH and PHN equivalents and a combustion source (e.g., automobile, ships) for BaP equivalents. The ratio BaP/PHN equivalents (0.05 ± 0.07, n = 37) confirms the predominance of petrogenic PACs for contamination by these chemicals in this region.  相似文献   

3.
Green-lipped mussels (Perna viridis) were collected from seven fish culture zones (FCZs) in Hong Kong and analyzed for okadaic acid (OA). A conventional HPLC method was modified by incorporating a proteinase K digestion step. Results suggest that a higher recovery (2.5 times higher) of OA was obtained from spiked samples after the addition of 1.08 mg proteinase K in comparison with samples incubated without the proteolytic enzyme. For the hepatopancreas (HP) of individual field-collected mussels, the additional digestion step can enhance OA extraction by 3.1 times. Spatial and temporal variations in OA concentrations in the mussels from various FCZs were investigated. The highest concentration of OA in mussel HP samples was 1164.9 ng/g HP wet wt. With respect to OA concentrations in whole mussel tissues from seven sites and four seasonal samplings, the concentrations were between 70.0 and 131.0 ng/g wet wt., which did not exceed the generally recognized international regulatory criteria (>200 ng/g) for OA.  相似文献   

4.
The accumulation of crimidin in total samples and in some organs of five fish species was studied under experimental conditions. The species were Cyprinus carpio, Carassius carassius, Tinca tinca, Scardinus erythrophthalmus and Leucaspius delineatus. Fish were exposed to concentrations of 10 mg · l?l and 50 mg · l?1. During short-term experiments water and fish samples were taken at intervals of t = 0, 6, 12, 24, 48 and 72 hours, during the long-term experiment sampling was performed weekly for six weeks. Total samples were analysed for C. carassius, T. tinca, S. erythrophthalmus and L. delineatus. Samples of individual organs and tissues were taken as follows: C. carpio – gills, digestive tract, muscular tissue, kidneys, gonads; C. carassius – gills, digestive tract, muscular tissue, ovaries, testes. Crimidin was determined by gas chromatography. In samples from the short-term experiments at a concentration of 10 mg · l?1 in the water the amount was roughly 101–10 mg · kg?1, at a concentration of 50 mg · l?1 in the water roughly 101 mg · kg?1. In most cases the accumulation coefficient was lower than 1.0. The accumulation capacity of individual fish species did not differ greatly. Of the internal organs only the kidneys had a high accumulation capacity, otherwise the highest values were found in muscular tissue and the gills. After one – three weeks the amount of crimidin in most organs falls, and after transfer to clean water there is a general sharp decline. Thus crimidin is not firmly bound in the body.  相似文献   

5.
千岛湖(新安江水库)是我国大水面生态渔业发展的典型湖库,其渔业主要以鲢、鳙等滤食性鱼类增殖为主,对鱼食性鱼类资源的研究和关注相对匮乏。而鱼食性鱼类是水生食物网的顶级捕食者,对维持水生态系统结构和功能具有重要作用。近年来,受过度捕捞、生境退化等影响,千岛湖鱼食性鱼类资源下降明显。鉴于此,2021年3月—2022年12月,逐月在千岛湖收集4种同域共存的鱼食性鱼类样品1032尾,包括翘嘴鲌(Culter alburnus)、蒙古鲌(Culter mongolicus)、大眼鳜(Siniperca knerii)和斑鳜(Siniperca scherzeri),系统研究并比较了4种鱼食性鱼类年龄、生长、繁殖等生活史策略的分化特征。结果表明,千岛湖4种鱼食性鱼类优势年龄组均未超过3龄,说明其种群呈现低龄化现象。生长式型上,翘嘴鲌和蒙古鲌属正异速生长,而大眼鳜和斑鳜属负异速生长,说明4种鱼食性鱼类具有不同的生长策略。条件系数(CF)的变化趋势与繁殖活动密切相关,其中大眼鳜的条件系数最高(1.92%±0.03%),其次为斑鳜(1.72%±0.02%)和蒙古鲌(1.14%±0.01%),翘嘴鲌的条件系...  相似文献   

6.
The objective of this paper is to compare the trend of polychlorinated biphenyls (PCBs) bioaccumulation in three species of Lake Ontario salmonids with similar diet patterns and habitat. The concept of bioenergetics, which relates the growth and energy expenditure of a fish directly to its food consumption, is integrated into the study of pollutant accumulation. The resulting bioaccumulation model is a comprehensive approach that combines the physiological information of the fish, such as diet, metabolism, respiration, habitat, age and species, with the environmental conditions in the lake. The three species of salmonids studied are Lake Trout (Salvelinus namaycush), Brown Trout (Salmo trutta), and Chinook Salmon (Oncorhynchus tshawytscha). The model, which relies on a lakewide water quality and fish sampling database from the Ontario Ministry of Environment and Energy, is applied to study the pattern of total body burden of PCBs over the life span of the fish. Results from the model compare favorably to the data, and the observations clearly demonstrate the relative effects of food and water contamination on the time-dependent accumulation of PCBs in the bodies of fish. It is observed that different species sharing the same habitat and exposed to similar water contaminant concentrations are exhibiting marked difference in the body accumulation of PCBs. This difference is successfully reproduced with the model through judicious representation of their diet preferences and generically-governed metabolisms.  相似文献   

7.
The fish Cyprinus carpio (HAM.) and Channa punctatus (BL.) of the size ranging between 6.0 ± 1.2 cm and 28.0 ± 1.6 cm were exposed to different concentrations of industrial effluents from M/s Punjab Tannery Ltd. (Jalandhar), M/s Spinning Mill Ltd. (Hoshiarpur) and M/s Food Specialist Ltd. (Moga) for evaluating the influence of fish size on the acute toxicity of these effluents. Results indicate that the relative toxicity of the effluents decreased with the increase in fish size from 6.0 ± 1.2 cm to 20.6 ± 1.5 cm. However, for specimens of the size of 28.0 ± 1.6 cm and more, the toxicity of the effluents increased with an increase in fish size. On the basis of the relative toxicity to fish, effluent from Punjab Tannery was found highly toxic and from Food Specialist Industry, the least toxic.  相似文献   

8.
鄱阳湖产银鱼的繁殖生物学   总被引:7,自引:1,他引:6  
陈国华  张本 《湖泊科学》1990,2(1):59-67
本文记述了鄱阳湖产太湖短吻银鱼(Neosalanx tangkahkeii taihuensis)、乔氏短吻银鱼(Neosalanx jordani)、雷氏银鱼(Reganisalanx brachyrostralis)等三种银鱼的成熟年龄、繁殖时期、生殖群体的体长、性比、生殖力、卵的特征等繁殖生物学资料,并记述了太湖短吻银鱼性腺成熟系数的周年变化、太湖短吻银鱼和乔氏短吻银鱼的产卵生态条件等。近二十年来鄱阳湖银鱼产量急剧下降的主要原因是产卵场遭到了严重破坏。银鱼生命周期仅一年,繁殖力强,认为加强繁殖保护、合理安排捕捞时间是恢复鄱阳湖银鱼资源的关键措施。  相似文献   

9.
10.
Unionid mussels are highly imperiled and the survival of their local populations is linked to the availability and dispersal potential of their host fish. We examined the displacement distance of logperch (Percina caprodes), which are obligate host fish for endangered snuffbox mussels (Epioblasma triquetra), to determine the dispersal potential by fish. Logperch in the Sydenham River, Ontario, Canada, were electrofished and marked with visible implant elastomer on five sampling dates during the gravid period of E. triquetra. The majority of all recaptures (82%) of P. caprodes occurred within 30 m of their original capture location, with a mean displacement distance of 13 ± 3 m (mean ± standard error, n = 28). These results were consistent with a review of movement studies of small benthic host fish (i.e., darters and sculpins), which revealed average fish displacement distances of 37 ± 19 m (n = 14 species; range: 4–275 m). However, significantly greater movement distances were also found and the maximum displacement distance increased significantly with the spatial extent of the study and with the duration of the study. These results indicate that many P. caprodes remain in a small area, which could restrict the dispersal and (re)colonization potential of E. triquetra. Further studies are needed to determine the dispersal potential of mussels via host fish, which may be important for maintaining the connectivity among unionid populations.  相似文献   

11.
2009年8月采集了巢湖河流及湖泊表层水体共15个样点,利用固相萃取-气相色谱-电子捕获检测器(SPE-GC-ECD)方法测定滴滴涕类(DDTs)农药的含量,分析了其残留特征、来源及风险.结果表明:1)巢湖丰水期DDTs含量范围为1.52-21.79ng/L,平均含量为9.98±4.73ng/L.2)DDT残留主要来自...  相似文献   

12.
Data on the occurrence and accumulation profiles of butyltins (BTs), including tributyltin (TBT), in marine mammals are scarce. This is the first study to investigate residue levels and accumulation patterns of BTs in cetaceans from Korean coastal waters. The total concentrations of BTs (sum of mono- to tri-butyltins) in minke whales (Balaenoptera acutorostrata) and long-beaked common dolphins (Delphinus capensis) ranged from 15.7 to 297 ng/g wet weight (mean: 100 ng/g wet weight) and from 59.0 to 412 ng/g wet weight (mean: 228 ng/g wet weight), respectively. Dibutyltin (DBT) accounted for 63% of the total BTs in all cetacean samples. Significant species-specific differences in BT concentrations, possibly due to the differences in their habitat and diet, were found between the two cetacean species. The concentrations of DBT and TBT in most cetacean samples exceeded the threshold value for cytotoxic effects in cetaceans, implying potentially adverse health risks from exposure to BTs.  相似文献   

13.
三峡水库调度运行改变了库区江段的水文情势,影响漂流性卵苗在库区江段内的时空分布特征。在水库低水位运行时,具有流水生境特征的库中和库尾江段是产漂流性卵鱼类在整个三峡库区内重要的产卵江段。了解三峡库中和库尾江段产漂流性卵鱼类的早期资源状况及其对水文和水温特征的响应关系,对于采取适宜的保护措施促进鱼类早期资源的恢复具有重要的意义。本文通过2017—2020年5—7月在库中涪陵断面进行的逐日早期资源监测,了解三峡库中和库尾江段产漂流性卵鱼类早期资源的种类组成、产卵规模、产卵场分布及其年际变动特征,并采用随机森林(RF)模型,分析鱼类逐日产卵规模变动与水文、水温格局及其过程的关系,辨识影响不同种类产卵规模变动的关键水文及水温要素。结果表明:2017—2020年共采集到漂流性鱼卵21种,包括长江上游特有鱼类鱼卵3种;以圆筒吻鮈Rhinagobio cylindricus、蒙古鲌Chanodichthys mongolicus、贝氏(?)Hemiculter bleekeri等6种鱼类的鱼卵为主,占总采集鱼卵数的88.76%;各年的鱼卵规模分别为83.04×108、14.29×...  相似文献   

14.
Monocrotophos (0,0-dimethyl-0-(1-methyl-2-N-methyl-carbamoyl)-cis-vinylphosphate) as an active component of some insecticides is highly soluble in water at a low hydrolysis rate: half-time at 2 mg/l, pH = 7.0 and 38 °C 23 d. Individuals of the following fish species (individual weight in g) were kept during the static bioassay for 6… 72 h at 40 mg/l monocrotophos in the medium: Cyprinus carpio (70), Carassius carassius (45) and Leucaspius delineatus (1.5), and then the concentration of monocrotophos was gas-chromatographically determined in different tissues. Initially, till the 24th hour a high accumulation in the gills took place (in mg/kg fresh weight: Cyprinus 0.49, Carassius 3.88), then the concentration remained uniform or slightly falling here, whereas in the other organs (digestive organs, muscle, gonads) a further accumulation up to 1 mg/kg occurred. Leucaspius was investigated only as whole individuals, and after 72 h their fresh weight had increased to 6.96 mg/kg. The rates of accumulation decrease in the following order: Cyprinus: digestive organs, gills, muscle; Carassius: gills, digestive organs, gonads, muscle.  相似文献   

15.
水体生态环境中的微塑料与重金属污染问题正日益受到热切关注为探讨微塑料与重金属对水产品的复合生态效应,选择鄱阳湖饶河段优势淡水鱼为研究对象,对鱼体内微塑料及重金属Cu、Cd、Pb、Zn、Cr等元素的生物累积作用进行分析与评价结果表明:调查区域水环境中微塑料的丰度范围10~64 items/L,平均值38.56 items/L. 8种淡水鱼消化道微塑料丰度范围为1.21~9.11 items/g,平均丰度为5.40 items/g;鳃部丰度范围0.61~5.00 items/g,平均丰度为2.87 items/g;微塑料类型主要有碎片类、纤维类、薄膜类和颗粒类4种,其聚合物成分主要为聚乙烯(PE)、低密度聚乙烯(LDPE)、聚丙烯(PP)和聚苯乙烯(PS);颜色以透明及彩色为主;微塑料粒径范围为0.01~9.5 mm,粒径0.5 mm的微塑料所占比例为79.07%,鱼体内与其生存水环境中微塑料的丰度特征(形态、粒径、颜色和聚合物类型组分比例)具有一定相似性各鱼类对微塑料的累积系数(BAF)平均值为178.29,不同鱼类累积微塑料的能力大小次序为:乌鳢(Channa argus)、黄颡鱼(Pelteobagrus fulvidraco)鲦鱼(Hemicculter leuciclus)、草鱼(Ctenopharyngodon idellus)、鲶鱼(Silurus asotus)鲤鱼(Cyprinus carpio)、刀鱼(Coilia ectenes)、鲫鱼(Carassius auratus)鱼体肌肉组织内重金属Cu、Cd、Pb、Zn、Cr的平均含量分别为4.27、0.13、0.28、11.73、0.53 mg/kg,均符合无公害水产品的要求且低于人体消费卫生标准,属于安全食用范围;鱼类对5种不同重金属的累积能力大小次序为ZnCuCdPbCr,不同鱼类对不同重金属的累积能力具有差异性通过扫描电镜(SEM)与能谱分析(EDS)检测到各类型微塑料表面均有上述5种重金属元素,证实微塑料可能成为重金属的附着载体,相关性分析表明微塑料与Cu呈极显著相关,与Cd、Pb均呈显著相关;微塑料的存在一定程度上会增强Cu、Cd与Pb的累积效应,并可能产生复合污染效应.  相似文献   

16.
17.
Persistent organochlorine pollutants (POPs) are analyzed for the dropping-amended soils from the habitats of Antarctic seabirds and seals in Fildes Peninsula and Ardley Island. The concentration ranges are 0.21 to 3.85 ng/g for polychlorinated biphenyls (ΣPCBs),0.09 to 2.01 ng/g for organochlorine pesticides (ΣDDT),and 0.06 to 0.76 ng/g for hexachlorocyclohexanes (HCHs). Among these,hepata-chlorobiphenyls,hexachlorobiphenyls,p,p′-DDE and α-HCH compounds are dominant. The concentra-tion ranges of ΣPCB,DDT and HCH in the eggs of skuas were 91.9―515.5 ng/g,56.6―304.4 ng/g and 0.5―2.0 ng/g respectively; those in the eggs of penguins were 0.4―0.9 ng/g,2.4―10.3 ng/g and 0.1― 0.4 ng/g; and those in the eggs of giant petrel were 38.1―81.7 ng/g,12.7―53.7 ng/g and 0.5―1.5 ng/g respectively. The dominant POP compounds in the eggs are PCB180,PCB153,p,p′-DDE and hexa-chlorobenzene (HCB). The present study shows that the concentration of POPs in the sea-bird-inhabited-dropping-amended soil varies with the extent of predation and nest occupancy of dif-ferent seabird populations. Statistical analysis on the POP concentrations from the different seabird eggs implies that the difference in the bio-concentration levels of the birds depends on the bio-habits of the species,such as the range of activity,distance of immigration,feeding pattern,and nest occupation. Among these,the most important factor is the location of the seabirds in the food chain and their feeding pattern. This shows that POPs accumulated in the seabirds resulted from the bio-concentration through the food chain. In addtion,210Pb dating for the dropping-amended soils (AD1-a and AD2) was performed,which provided the POP accumulation rate and the historic record for the soil profile. It indicates that POP will continuously affect the Antarctic ecosystem for a long time.  相似文献   

18.
Trace organic (chlorinated pesticides, PCBs, PAHs and dioxins/furans) and trace metal concentrations were measured in surficial sediment and biological tissues (i.e., worms, crustaceans, bivalve molluscs, and fish livers) collected from the Russian Arctic. Total DDT, chlordane, PCB and PAH concentrations ranged from ND to 1.2, ND to <0.1, ND to 1.5 and <20-810 ng g(-1), respectively, in a suite of 40 surficial sediment samples from the Kara Sea and the adjacent Ob and Yenisey Rivers. High sedimentary concentrations of contaminants were found in the lower part of the Yenisey River below the salt wedge. Total dioxins/furans were analysed in a subset of 20 sediment samples and ranged from 1.4 to 410 pg g(-1). The highest trace organic contaminant concentrations were found in organisms, particularly fish livers. Concentrations as high as 89 ng g(-1) chlordane; 1010 ng g(-1) total DDTs; 460 ng g(-1) total PCBs; and 1110 ng g(-1) total PAH, were detected. A subset of 11 tissue samples was analysed for dioxins and furans with total concentrations ranging from 12 to 61 pg g(-1). Concentrations of many trace organic and metal contaminants in the Kara Sea appear to originate from riverine sources and atmospheric transport from more temperate areas. Most organic contaminant concentrations in sediments were low; however, contaminants are being concentrated in organisms and may pose a health hazard for inhabitants of coastal villages.  相似文献   

19.
Fish, Cyprinus carpio and Channa punctatus in four sizes (6.0 ± 1.2; 12.5 ± 1.6; 20.6 ± 1.5 and 28.0 ± 1.8 cm in total length) were exposed to industrial effluents from the Sangam Dyeing Factory (Ludhiana), the Sterling Steel and ABC Paper Mills (Hoshiarpur) to evaluate the acute toxicity of these effluents at different fish sizes. Results reveal that the toxicity of industrial effluents decreased with the increased fish size from 6.0 ± 1.2 to 20.6 ± 1.5 cm in length. However, for specimens of the size of 28.0 ± 1.6 cm and more, the toxicity of the effluents increased with an increase in fish size. On the basis of the relative toxicity to fish, effluent from the Sterling Steel Mill was found to be highly toxic to fish and effluent from the Dyeing Factory least toxic except for the fish of 6.0 ± 1.2 cm at which dyeing factory effluent was most toxic and ABC paper mill effluent the least toxic.  相似文献   

20.
Perfluorinated alkyl compounds (PFCs) including perfluorooctane sulphonate (PFOS) and perfluorooctanoate (PFOA) were measured in environmental samples collected from around Homebush Bay, an urban/industrial area in the upper reaches of Sydney Harbour and Parramatta River estuary. Water, surface sediment, Sea Mullet (Mugil cephalus), Sydney Rock Oyster (Saccostrea commercialis) and eggs of two bird species; White Ibis (Threskiornis molucca), and Silver Gull (Larus novaehollandiae) were analysed. In most samples PFOS was the dominant PFC. Geometric mean PFOS concentrations were 33 ng/g ww (wet weight) in gull eggs, 34 ng/g ww in ibis eggs, and 1.8 ng/g ww and 66 ng/g ww in Sea Mullet muscle and liver, respectively. In sediment the PFOS geometric mean was 1.5 ng/g, in water average PFOS and PFOA concentrations ranged from 7.5 to 21 ng/L and 4.2 to 6.4 ng/L, respectively. In oysters perfluorododecanoic acid was most abundant, with a geometric mean of 2.5 ng/g ww.  相似文献   

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