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甲基汞(MeHg)对鱼类多种生命过程存在极强的毒性作用,但有关其对海水鱼类免疫功能的毒性作用研究较少。本文利用实验毒理学方法研究了MeHg(暴露浓度0.0, 0.1, 1.0, 10.0, 20.0μg/L;暴露时间30天)在褐牙鲆(Paralichthys olivaceus)幼鱼组织(鳃、肝脏和脾脏)中的蓄积特征及其对幼鱼的四种免疫功能生物指示物(溶菌酶LZM、酸性磷酸酶ACP、碱性磷酸酶AKP和免疫球蛋白MIgM)和生长的毒性作用。结果表明,幼鱼体内MeHg蓄积量具有显著的浓度依赖性和组织特异性,各组织对MeHg的蓄积能力总体上呈现肝脏鳃脾脏的趋势;四种免疫功能生物指示物(活性或含量)对不同MeHg浓度暴露的响应方式各异,且具有显著的组织特异性; MeHg达到一定暴露浓度后显著抑制幼鱼的生长。总体而言,MeHg在褐牙鲆幼鱼体内蓄积,对其产生免疫毒性,并抑制幼鱼的生长。此外,ACP、AKP和LZM等免疫性指标能较好的反映对MeHg暴露的浓度依赖关系和组织特异性,可作为海水环境中MeHg污染风险评估和生物毒性分析的潜在生物指示物。 相似文献
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根据2009-04—2010-02对桑沟湾9个调查站位贝类养殖区重金属的调查资料,分析该海域海水、沉积物和养殖贝类体内铜(Cu)、铅(Pb)、锌(Zn)、镉(Cd)、汞(Hg)、甲基汞(MeHg)和砷(As)的含量水平,就重金属污染对海洋环境质量的影响进行综合评价和类别划分,并对食用贝类中重金属的暴露水平进行健康风险评估。结果表明,桑沟湾贝类养殖区海水质量、沉积物质量和养殖贝类质量水平范围为1~3级,平均分别为1级、3级和2级,养殖生态环境综合质量水平为2级;总体上,该海域海洋环境综合质量处于良好水平,贝类产区生态环境质量为1类区(清洁区)。这表明该海区重金属污染对海洋环境质量影响较小或无明显影响。另外,针对食用桑沟湾贝类水产品的消费人群进行了重金属污染的健康风险评估,结果表明调查人群食用贝类中Pb,Cd,Hg,MeHg和As的日摄入量(DI)值分别为15.67,62.02,0.001 8,0.001 6和0.188μg/(人·d),摄入量低于食品添加剂联合专家委员会(JECFA)的推荐限值,因此桑沟湾食用贝类中重金属污染的健康风险处于安全范围。 相似文献
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通过向水体中通入CO_2的方法模拟海洋酸化环境,测定青蛤(Cyclina sinensis)在酸化条件下各免疫指标的变化情况。结果显示:将青蛤置于酸化的海中(pH分别为7.4和7.7),并以自然海水做对照组(pH 8.1)后,血细胞总数随海水酸化胁迫时间的延长,表现为下降趋势,且差异显著(P0.05);海水pH降低抑制了溶菌酶的活性,但差异性不显著(P0.05);ACP活性总体呈下降趋势,对照组活性要高于酸化组,而ALP活性表现为上升趋势。酸化胁迫初期诱导SOD活性升高,后期SOD活性受到抑制,而CAT变化却截然相反;脂质过氧化产物MDA在酸化后期出现显著降低(P0.05)。 相似文献
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大气中二氧化碳浓度增加造成海洋酸化并改变海洋化学环境,可能对海洋生物造成不利影响。桡足类是海洋生态系统中重要的次级生产者,研究桡足类如何应对海洋酸化的影响对海洋生态风险评估具有重要作用。本文分别在自然海水(pH 8.1,对照)和二氧化碳酸化海水(pH 7.3)条件下培养日本虎斑猛水蚤(Tigriopus japonicus Mori,1938),研究海水酸化对其发育、繁殖以及ATP酶活性的影响效应。结果显示,海水酸化能使日本虎斑猛水蚤无节幼体发育时间显著延长并使雌体产生的无节幼体数量显著减少,Na~+/K~+-ATP酶和Ca~(2+)-ATP酶活性在酸化条件下均显著增强。研究结果表明,海水酸化胁迫下日本虎斑猛水蚤能量消耗增加,应用于发育和繁殖的能量可能减少,从而引起早期幼体发育延滞和雌体繁殖力下降的负面反应。 相似文献
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随着CO2的大量排放,海洋酸化效应不断加重,为探究未来海水酸化情况对菲律宾蛤仔产生的影响,设置对照组(pH为8.1)和酸化组(pH为7.7、7.1和6.4),研究周期为42 d,测定菲律宾蛤仔在酸化条件下组织结构、免疫和抗氧化酶活性的变化情况,以及在分子水平上产生的影响。结果表明：菲律宾蛤仔置于酸化海水环境中,鳃丝间距随pH的降低而扩大,鳃丝纤毛黏合,水管和外套膜外表皮褶皱逐渐加深;鳃组织中酸性磷酸酶(ACP)和超氧化物歧化酶(SOD)活性变化情况为先降后升,碱性磷酸酶(AKP)活性各组变化趋势不同,总抗氧化能力(T-AOC)、过氧化氢酶(CAT)和溶菌酶(LZM)活性趋势为先升后降;鳃和内脏团谷胱甘肽过氧化物酶(GSH-Px)活性变化规律皆为持续上升;内脏团组织中LZM活性变化趋势各不相同,ACP活性变动趋势为先降后升,AKP、SOD和CAT活性变化规律为先升后降,T-AOC趋势为持续下降;通过转录组的分析得到,鳃组织GO功能主要富集在DNA整合、膜的组成部分和RNA定向DNA聚合酶活性等条目中,KEGG通路主要富集在吞噬体和与蛋白合成的相关通路中。海水酸化使菲... 相似文献
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随着人类工业迅速发展, CO2大量排放,引起了海洋的酸化效应,不仅导致了全球气候变暖,也严重危害了海洋生物的生态健康。以菲律宾蛤仔(Ruditapes philippinarum)为研究对象,研究pH变化对菲律宾蛤仔耗氧率、排氨率、鳃组织结构以及鳃和内脏团的免疫、抗氧化酶活性的影响。将菲律宾蛤仔置于酸化海水(pH 6.4、7.1和7.7)中,以自然海水(pH 8.1)为对照。结果表明:耗氧率和排氨率随着pH的升高或降低而降低,在pH=8时达到最大值; 6.4酸化组蛤仔鳃组织结构损伤严重,鳃丝间距扩大,纤毛黏合;鳃组织碱性磷酸酶(AKP)第42天所有酸化组活性显著高于对照组(P<0.05),所有酸化组溶菌酶(LZM)和酸性磷酸酶(ACP)活性显著低于对照组(P<0.05), 7.7酸化组超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)活性和总抗氧化能力(T-AOC)显著高于对照组(P<0.05),所有酸化组丙二醛(MDA)含量显著低于对照组(P<0.05);内脏团7.1和7.7酸化组LZM活性显著高于对照组(P<0.05),... 相似文献
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栉孔扇贝是我国海水养殖业的重要品种之一,但养殖扇贝陆续暴发大规模细菌性疾病,造成了巨大的经济损失。深入研究扇贝的免疫防御机制,是改良种质、培育抗病品系的必要措施。近年来研究发现,Smad基因可以通过调控增强子结合蛋白(CEBP/ε)来促进中性粒细胞的成熟和功能极化,在引发脊椎动物的先天免疫调节中发挥着重要的作用。然而目前对于Smad及其在免疫中的作用的研究大都集中于脊椎动物中,在海洋贝类中的研究还较为匮乏。因此,对栉孔扇贝的Smad基因家族进行了系统发生、共表达网络的构建、以及鳗弧菌侵染的免疫应答分析,以解析贝类Smad基因家族的表达调控机制和在免疫应答中的作用。结果表明,Smad3和Smad6可能在两侧对称动物的共同祖先中位于同一染色体上;栉孔扇贝Smad5与Toll样受体信号通路的关键基因协同表达;受鳗弧菌侵染后,血淋巴中的Smad5显著上调,说明Smad5基因可能通过与Toll样受体信号通路相互作用,参与了机体的免疫应答。研究结果可为深入研究贝类Smad基因在天然免疫系统中的作用提供重要参考。 相似文献
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在人类的生产生活过程中,排出的各种废弃物通过各种途径进入并在海洋累积起来,使海 洋中的贝类生存环境日趋恶化.本文根据国内外关于环境污染因子在海洋贝类体内的生物累积方面的研究成果,介绍累积性环境污染因子(重金属、石油烃、典型有机物)在贝类体内的生物累积(包括吸收,转运,累积等生理过程)以及毒理危害的研究进展. 相似文献
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The aim of the present study was to investigate seasonal and spatial patterns of soil oxygen consumption, nitrification, denitrification and fluxes of dissolved inorganic nitrogen (DIN) in a tidal salt marsh of the Lagoon of Venice, Italy. In the salt marsh, intact soil cores including overlying water were collected monthly at high tide from April to October in salt marsh creeks and in areas covered by the dominant vegetation, Limonium serotinum. In May, cores were also collected in areas with vegetation dominated by Juncus maritimus and Halimione portulacoides. In laboratory incubations at in situ temperature in the dark, flux rates of oxygen and DIN were monitored in the overlying water of the intact cores. 15N-nitrate was added to the overlying water and nitrification and denitrification were measured using isotope-dilution and -pairing techniques. The results show that highest soil oxygen consumption coincided with the highest water temperature in June and July. The highest denitrification rates were recorded in spring and autumn coinciding with the highest nitrate concentrations. Soil oxygen consumption and nitrification rates differed between sampling sites, but denitrification rates were similar among the different vegetation types. The highest rates were recorded in areas covered with L. serotinum. Burrowing soil macrofauna enhanced oxygen consumption, nitrification and denitrification in April and May. The data presented in this study indicate high temporal as well as spatial variations in the flux of oxygen and DIN, and nitrogen transformations in the tidal salt marshes of the Venice lagoon during the growth season. The results identify the salt marshes of the Venice lagoon as being metabolically very active ecosystems with a high capacity to process nitrogen. 相似文献
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Caterina Casagranda Mohamed Sadok Dridi Charles Franois Boudouresque 《Estuarine, Coastal and Shelf Science》2006,66(3-4):437-446
Abundance, population structure and production of the macro-invertebrates belonging to the functional feeding group of the shredders were studied in the Ichkeul wetland, northern Tunisia, from July 1993 to April 1994. Mean above-ground macrophyte biomass was at a maximum in September followed by a complete breakdown of the Potamogeton pectinatus L. meadow from October onward due to high salinity following an exceptionally dry winter. Only the meadow of Ruppia cirrhosa (Petagna) Grande at Tinja remained in place. Abundance of Gammarus aequicauda (Martynov 1931), Idotea chelipes (Pallas 1766) and Sphaeroma hookeri Leach 1814 was significantly related to the R. cirrhosa biomass. Gammarus aequicauda presented two recruitment periods in spring and autumn, and S. hookeri a third one in winter. The population of I. chelipes was renewed during winter by continued reproduction without any spring generation. Recruitment of all three species was not very successful during the study period. Life span of all three species was between 12 and 15 months. Despite their relatively low biomass and production rate, the shredders have a key function in processing macrophyte matter to different trophic levels through fragmentation and accelerating the decomposition of macrophyte biomass accumulated at the end of the growth season in the Ichkeul lagoon. 相似文献
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Barik Tapan K. Swain Surya N. Sahu Bijayalaxmi Tripathy Bibarani Acharya Usha R. 《海洋学报(英文版)》2020,39(6):26-35
Marine ecosystems provide a wide variety of diverse habitats that frequently promote migration and ecological adaptation. The extent to which the geographic distribution of marine organism has reshaped by human activities remains underappreciated. The limitations intrinsic to morphology-based identification systems have engendered an urgent need for reliable genetic methods that enable the unequivocal recognition of fish species,particularly those that are prone to overexploitation and/or market substitution. In the present study, however, an attempt has been taken to identify two locally adapted fish species, Siganus sutor(Valenciennes, 1835) and Seriolina nigrofasciata(Rüppell, 1829) of order Perciformes, which happens to be the first record in Odisha coast,Bay of Bengal. The diagnostic characteristics of Siganus sutor are: dorsal fin XIII-10, anal fin VII-9, pectoral fin 15,pelvic fin II-3, while that of Seriolina nigrofasciata dorsal fin VI-I-35, anal fin I-17, pectoral fin 16, pelvic fin 5. All COI barcodes generated in this study were matched with reference sequences of expected species, according to morphological identification. Bayesian and likelihood phylogenetic trees were drawn based on DNA barcodes and all the specimens clustered in agreement with their taxonomic classification at the species level. The phylogeographic studies based on haplotype network and migration rates suggest that both the species were not panmitic and the high-frequency population distribution indicates successful migration. The result of this study provides an important validation of the use of DNA barcode sequences for monitoring species diversity and changes within a complex marine ecosystem. 相似文献
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Birds, seals and the suspension culture of mussels in Bantry Bay, a non-seaduck area in Southwest Ireland 总被引：1，自引：0，他引：1
Concerns about the environmental impacts of mariculture have grown in recent years in response to the rapid expansion of the industry. The blue mussel (Mytilus edulis) is the main product of shellfish mariculture in the Northeast Atlantic and Baltic Sea, with approximately one third of the harvest cultured using suspended longlines within sheltered marine areas. The main aim of this study was to examine the interactions, and assess the impacts (if any) of mussel suspension culture on the seabird and seal community, employing a simultaneous study of culture and control sites. The study spanned a 20-month period (from November 2001 to August 2003) and encompassed six sites in Bantry Bay (Southwest Ireland).There was no significant difference in species richness between mussel and control sites. Similarly, species diversity did not significantly differ between the mussel and control sites although control sites were generally more diverse than mussel sites, the latter particularly dominated by large numbers of Laridae.Significantly higher numbers of Phalacrocoracidae, Laridae and Alcidae were recorded in mussel sites than in control sites. However, no significant difference was found between Gaviidae or common seal (Phoca vitulina) numbers in mussel and control sites. Seasonal patterns of abundance were similar in mussel and control sites, with peak numbers of most species groups occurring in spring.Mussel suspension culture does not appear to have an adverse effect on the abundance of seabirds or common seals in this area. The safe perching platforms provided by suspension culture floats, combined with a number of other factors, contribute to an increased abundance of a number of seabird species, particularly Laridae. The possible interactions between vertebrate predators and mussel suspension aquaculture are discussed and possible explanations for the increased seabird abundance observed in these areas are offered. 相似文献
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Emmanuelle Buecher 《Journal of Sea Research》1999,41(4):95
The vertical and temporal distribution of two calycophoran siphonophores, Chelophyes appendiculata (Eschscholtz, 1829) and Abylopsis tetragona (Otto, 1823) in the Bay of Villefranche (northwestern Mediterranean) was investigated by an analysis of three different planktonic time series. A daily series (1993–1995) showed seasonal peaks of the nectophores of C. appendiculata during spring and particularly in late summer, while the abundance of A. tetragona remained similar throughout the year. A weekly series (1994–1995) showed that C. appendiculata (nectophores and eudoxids) became concentrated above the thermal discontinuity, in the most stratified and warm waters, whereas A. tetragona was collected in large numbers below this discontinuity. A 27-year survey (1966–1993) showed long-term fluctuations of these siphonophore populations, which became abundant in the Bay starting from 1980 and especially after 1984, when the water column grew warm and hypersaline, corresponding to a less rainy period. Temporal (seasonal and long-term) and bathymetric (between 10 and 60 m depth) successions of these two siphonophores were noted in this shallow coastal bay. 相似文献
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为了解广西北部湾海域钝缀锦蛤(Tapes conspersus)精巢周年发育情况、精子发生过程及成熟精子超微结构,本文采用组织切片、扫描电镜、透射电镜技术对钝缀锦蛤精巢发育过程、精子的发生及超微结构进行了研究。研究结果显示:目前广西北部湾钝缀锦蛤未见雌雄同体情况,观察的个体皆为雌雄异体。一周年的采样结果中,雌性个体138个、雄性个体102个,雌雄的性比约为1.35︰1。1年即为精巢发育的一个周期,发育时期可以划分为增殖期、生长期、成熟期、排放期、休止期共5个主要分期。精细胞的发育可以划分为5个主要分期,即精原细胞期、初级精母细胞期、次级精母细胞期、精细胞期、成熟精子期。精子全长约59.27 μm,属于鞭毛型,由头部、中部、尾部3个部分共同构成,精子头部呈圆锥型,由细胞核和顶体组成,顶体呈倒“V”型。电子在顶体的分布是不均匀的,顶体前部电子分布少,后部分布多。中部主要由两部分构成,即5个圆形排列的线粒体和一个中心粒复合体。轴丝与质膜两个部分共同构成了尾部,轴丝的双联体微管结构横切面表现为“9+2”型。此外,本实验观察到少部分精子尾部呈双尾结构。 相似文献
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经济海藻繁育、养殖及综合利用是海洋农牧业及工业的重要组成部分。20世纪经过几代人的努力，我国在海带、紫菜、裙带菜及龙须菜的繁育、养殖关键技术等方面成功取得突破，为这些海藻的产业化提供坚实的保障，为我国成为世界海藻大国奠定了基础。海藻养殖产业为人们提供了食品、藻胶及其它丰富的产品，这包括保健品、功能食品、化妆品及药物等。海藻养殖产业也对人类经济、社会的发展起到重要作用，通过吸收环境中的二氧化碳、氮和磷，为海洋生态环境的改善发挥了重要作用。本文对我国海藻繁育、养殖及综合开发的历程进行简要回顾，对当前我国、中国科学院海洋研究海藻研究与应用进行了总结，对海藻研究发展的未来进行了展望；适应海藻产业从量向质的方向转变，同时兼顾生态环境效益，为我国海藻研发及应用提供参考。 相似文献
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作者通过渗透压计分别测定各溶液的渗透压值,通过CASA精子分析系统,测定精子运动参数,分析、比较了渗透压、pH、葡萄糖及离子溶液对夏牙鲆(Paralichthys dentatus)精子激活及运动特征的影响。结果表明:夏牙鲆精子激活的渗透压范围为581~1260 mosm/kg;在特定的渗透压范围内(单位为mosm/kg),A组(581~650),B组(762~877),C组(931~1060),D组(1117~1260)中,与NaCl和KCl溶液相比较,葡萄糖溶液可以显著提高夏牙鲆精子激活后的运动率;在相对高渗条件下(1091~1180),经Ca Cl2400、EGTA400和无Ca~(2+)人工海水激活的夏牙鲆精子运动率存在显著差异;且夏牙鲆精子最适的激活p H范围是7~7.5。综上,激活剂的渗透压决定了夏牙鲆精子能否激活并显著影响了激活后精子的运动率,同时葡萄糖、外源Ca2+及p H均在一定程度上影响了精子的运动率。 相似文献