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1.
为全面了解我国黄渤海鳗草(Zostera marina L.)床重金属污染水平, 本研究以大连林阳北海、葫芦岛兴城、唐山乐亭-曹妃甸和青岛湾四处鳗草床为研究对象。于夏季采集鳗草、海水和沉积物样品并分析其重金属(Cu、Zn、Pb和Cd)含量。以此分析海草的重金属富集特征, 并对比评估不同鳗草床重金属潜在生态风险。结果表明, 夏季四处鳗草床海水重金属含量由高到低依次为: Zn > Cu > Pb > Cd, 均低于国家一级水质标准; 对沉积物来说, 重金属含量由高到低依次为: Zn > Pb > Cu > Cd, 均低于国家一级沉积物质量标准。鳗草对重金属的富集因重金属种类和海草积累部位而异, 其地上组织对Cu、Zn、Cd的富集能力高于地下组织。研究区域海水中Cu、Zn、Pb和Cd潜在风险等级均处于低风险水平。而对沉积物而言, 葫芦岛兴城鳗草床Cd的潜在风险等级处于较高风险水平(Ei值为156.9)。唐山乐亭-曹妃甸和青岛湾鳗草床的地质累积指数(Igeo)由大到小依次为: Cd > Pb > Zn > Cu。综合所有元素的潜在生态风险指数(IR), 葫芦岛兴城鳗草床的潜在生态风险值最高。 相似文献
2.
威海荣成桑沟湾海域海草床分布现状及其生态特征 总被引：1，自引：0，他引：1
海草床是生物圈最高产的生态系统之一，在氮捕获、碳封存、水质净化及维持生物多样性等方面发挥关键作用。2016年8月通过对威海荣成桑沟湾海域的现场调查，发现分布总面积约为471.72 ha的海草床，种类为鳗草（Zostera marina）、红纤维虾形草（Phyllospadix iwatensis）、日本鳗草（Zostera japonica）和丛生鳗草（Zostera caespitosa），分布面积分别为395.33 ha、37.28 ha、32.74 ha和6.37 ha。鳗草分布范围较广，平均茎枝密度817.0±27.6 shoots/m2，平均生物量646.6±41.8 g DW/m2；红纤维虾形草主要分布于桑沟湾北部养殖池和南部楮岛海域，平均茎枝密度2 649.0±29.8 shoots/m2，平均生物量2 381.3±27.3 g DW/m2；日本鳗草主要分布于桑沟湾西部八亩地海域，平均茎枝密度506.0±26.2 shoots/m2，平均生物量118.3±12.5 g DW/m2；丛生鳗草主要分布于桑沟湾南部楮岛海域，其平均密度为513.0±17.9 shoots/m2，平均生物量为479.1±28.1 g DW/m2。结合历史资料，发现桑沟湾海域海草床严重退化，分析了海草床的退化原因并提出了相应的建议和对策，以期为海草资源及滨海生境修复提供参考。 相似文献
3.
工业革命以来，二氧化碳排放导致了海洋酸化。海水pH下降对无脊椎动物的生长发育、繁殖、代谢和免疫等多个生命过程产生重要影响，但海洋无脊椎动物如何感知和响应酸性pH胁迫的分子机制还很不清楚。本研究以团队建立的海洋线虫Litoditis marina品系为模型，对其在不同酸性pH条件下的表型特征及转录组数据进行了分析。结果表明，当pH从实验室最佳生长条件5.92下降到5.33时，L. marina生长发育的速度明显减慢，但依然可以产卵繁殖；但当pH下降到4.33时，L. marina的生长受到严重影响，表现为不能长成成体且不能产卵繁殖。通过转录组数据分析，发现当pH从5.92下降到4.33时，海洋线虫L. marina脂肪酸β-氧化通路基因和不饱和脂肪酸合成相关基因表达上调；表皮相关基因表达则呈现差异变化，2个nas基因和6个ptr基因表达显著上调，表皮胶原基因col类基因的表达没有发生显著变化；细胞色素P450通路相关基因、凝集素C基因和HSP70家族基因的表达量显著上调。当pH从5.92下降到5.33时，上述提到的这些上调基因中的大多数没有发生显著变化。我们发现的海洋线虫应答酸化胁迫的主要调控模式，为理解生物体能够在低pH环境中生存的分子机制提供了参考，为筛选和识别生物体响应和适应酸化胁迫的关键基因奠定了基础。 相似文献
4.
本研究采集了分布于中国东海的前肛鳗(Dysomma anguillaris)、短尾蛇鳗(Ophichthus brevicaudatus)、艾氏蛇鳗(Ophichthus evermanni)、海鳗(Muraenesox cinereus)、黑尾吻鳗(Rhynchoconger ectenurus)、微鳍新鳗(Neenchelys parvipectoralis)、大头蚓鳗(Moringua macrocephalus)、梅氏美体鳗(Ariosoma meeki)和星康吉鳗(Conger myriaster)9种鳗鲡目(Anguilliformes)鱼类,采用PCR技术扩增了线粒体COI基因片段序列, 结合GenBank数据库中下载的5种鳗鲡目鱼类同源序列, 分析比较了序列组成和差异, 并以光海鳝(Muraena argus)和细点海鳝(Muraena augusti)为外群, 基于最大似然法构建了鳗鲡目中6科11属14种鱼类的系统发育树, 探讨了该类群鱼类的系统进化关系。结果显示:72条序列共检测到43种单倍型, 4种碱基含量分别为27.4%(T)、28.2%(C)、25.8%(A)、18.6%(G), 平均A+T含量(53.2%)高于G+C含量(46.8%), 表现出明显的碱基组成偏好性。基于K2P(Kimura 2-parameter)模型计算得出不同种间的平均遗传距离为0.218 8, 不同属间的平均遗传距离为0.225 0, 不同科间的平均遗传距离为0.232 7, 分类阶元越高, 遗传距离越大。系统进化树显示蛇鳗科物种都能够形成独立的分支, 并得到有效的区分, 而其他类群存在混杂现象。以上结果表明, 由于鳗鲡目鱼类种类多且分布广,线粒体COI基因只适用于较低分类阶元(如科内属间、属内种间)间的物种鉴定, 该类群鱼类系统发育关系还有待于结合多种DNA条形码进行深入探讨。 相似文献
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采用实验生态学方法，通过分析摄食喜好系数、平均个体摄食量等参数，研究香螺（Neptunea arthritica cumingii）摄食选择性，以及温度、饵料状态对香螺摄食量的影响。结果表明，香螺成螺对不同的饵料具有明显的摄食选择性，喜食程度的顺序依次为缢蛏（Sinonovacula constricta）、菲律宾蛤仔（Ruditapes philippinarum）和毛蚶（Scapharca subcrenata）。随着温度的升高，不同规格香螺摄食量先升高后降低，摄食高峰出现在15℃，香螺对于已开壳饵料的摄食量显著高于未开壳饵料。 相似文献
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泥螺(Bullacta exarata)作为黄河三角洲区域成功引入的滩涂养殖种类, 为当地获得了巨大的经济效益, 但对其生态影响还了解不多。为了解该区域泥螺体内重金属含量并评价其生物质量, 于2012年8月对该区域进行泥螺和沉积物样品采集调查和分析。采用富集系数K、残留量指数I以及金属污染指数IMP进行分析。结果表明, 黄河三角洲沉积物及泥螺体内6种重金属含量均相对较低, 多数符合国家海洋沉积物质量标准第一类。泥螺对不同重金属的富集系数K有明显差别, 其中对Cu 和Cd 的富集能力最强。残留量指数I富集系数K及金属污染指数IMP均表明, 黄河三角洲潮间带泥螺对重金属的富集程度均较低, 说明该海域泥螺未受到重金属离子的污染。根据国家生物质量标准分析, 黄河三角洲潮间带泥螺的生物质量总体较好, 生物体内重金属含量总体上与海水中重金属含量无显著的相关性。 相似文献
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作为重要的免疫基因, NK-lysin参与了鱼类非特异性免疫系统对抗病原感染的免疫应答过程。在之前的研究中, 我们已经发现重要经济鱼类大黄鱼(Larimichthys crocea)体内存在2种类型的NK-lysin基因。在本文中我们报道了1种新型大黄鱼NK-lysin基因Lcnkl3, 并对基因序列、表达特征及其多肽片段的抗菌活性进行了分析。Lcnkl3基因的开放阅读框长度为435 bp, 编码144个氨基酸残基, 其多肽序列Lcnkl3中包含Saposin B结构域及6个高度保守的半胱氨酸残基。系统进化分析表明Lcnkl3与大黄鱼Lcnkl2最为相似, 与其他鱼类NK-lysin多肽则差异较大。Lcnkl3基因在未受感染的大黄鱼各组织中具有不同的基础表达量, 表达水平最高的组织为心脏。在病原诱导的免疫应答过程中, Lcnkl3基因在各组织不同感染阶段的表达模式存在差异。源于Lcnkl3成熟肽序列的多肽片段对不同细菌的抑制和杀灭效果差异显著。以上结果表明Lcnkl3属于大黄鱼NK-lysin基因家族, 并参与了大黄鱼对抗病原感染的免疫过程。 相似文献
8.
壳色是影响商品贝类经济价值的重要性状。本研究以不同壳色的硬壳蛤（Mercenaria mercenaria）群体为繁殖亲贝，采用个体间随机交配的方法，成功选育了白、红和杂3种壳色的子代群体，并在池塘培育至360日时测量了其壳长（X1）、壳高（X2）、壳宽（X3）及活体质量（Y），并使用相关性分析、主成分分析和通径分析等方法，探究了不同壳色硬壳蛤在幼虫期和稚贝期的生长性状差异及壳形态性状（壳长、壳高、壳宽）对活体质量的影响。研究结果表明：在幼虫期，与白色和红色群体相比，杂色群体生长速度更快、变态率更高，但存活率低（P<0.05）；在稚贝期，白色群体表现出显著的生长优势（P<0.05）。相关性分析结果显示，3种壳色硬壳蛤的壳形态性状（X1、X2、X3）与活体质量（Y）的相关系数均达极显著水平（P<0.01）。主成分分析和通径分析结果表明，硬壳蛤的壳长（X1）是影响其活体质量（Y）的主要因素。本研究结果能够为不同壳色硬壳蛤良种选育提供重要理论依据和基础数据。 相似文献
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全球气候和环境变化影响海洋动物的生长发育和繁殖等生命过程,探究环境因子调控发育的分子机制,需要深入了解海洋动物早期发育的生理和分子特征。以实验室驯化的潜在模式动物海洋线虫Litoditis marina为研究对象,对其胚胎期和孵化后发育早期2h、4h和6h的L1幼虫样品进行了转录组测序和分析。结果表明,2h、4h和6h的L1幼虫间差异较小,而三个L1幼虫样品与胚胎期相比,基因表达发生了显著变化。通过KEGG富集分析,发现与胚胎期相比,三个L1幼虫样品的多个通路如核糖体、核糖体生物发生、糖酵解/糖原异生、TCA循环和氧化磷酸化通路相关基因发生了显著上调。另外还发现多个神经递质和神经肽受体基因如dop-和npr-等在L1期转录水平显著上调。与胚胎期相比,L1幼虫的多个DNA复制和修复相关、Notch、Hippo和Hedgehog信号和剪切体等通路相关基因发生了显著下调。发现的L. marina早期发育转录组变化模式与已经发表的陆生模式生物秀丽线虫Caenorhabditis elegans从胚胎期到L1幼虫的转录组变化特征非常相似,但同一上调或下调通路中具体发生表达变化的基因有些不同。另外,L1幼虫显著上调的核糖体生物发生通路相关基因在秀丽线虫中发生了显著下调。进一步通过基因编辑等技术和方法深入研究发育调控关键基因的功能将为海陆近缘线虫间的发育进化机制、海洋线虫对潮间带环境适应以及全球气候变化应答的分子机制研究提供新认知。 相似文献
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CD55蛋白在哺乳动物中是一种补体调控因子,但其在鱼类中的功能未知。本研究探索了大菱鲆(Scophthalmus maximus) CD55(SmCD55)蛋白的功能。结果表明,SmCD55蛋白由344个氨基酸残基构成,含有一个N端信号肽和3个补体调控蛋白(CCP)功能域。SmCD55基因在大菱鲆多种组织中均有表达,其中,在肌肉中表达量最低,在脑组织的表达量最高。通过原核表达获得了重组的SmCD55(rSmCD55)蛋白,发现rSmCD55蛋白能够抑制大菱鲆血清的溶血活性和杀菌活性,表明其负调控补体系统的激活。此外,本研究还发现rSmCD55蛋白可以结合包括重要水产病原菌迟缓爱德华氏菌(Edwardsiella tarda)、荧光假单胞杆菌(Pseudomonas fluorescens)、鳗弧菌(Vibrio anguillarum)、哈维氏弧菌(Vibrio harveyi)和海豚链球菌(Streptococcus iniae)在内的多种细菌,其中与哈维氏弧菌的结合能力最强。以上这些研究结果丰富了鱼类补体系统的理论知识,加深了对鱼类补体激活调控的了解。 相似文献
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对实验室培养的两株海洋微藻海洋卡盾藻和中肋骨条藻的可培养细菌进行了分离鉴定，分别在海洋卡盾藻和硅藻中肋骨条藻不同生长时期分离得到48株和34株可培养细菌，去除重复序列后得到12株不同的菌株。这些菌株分属α-变形杆菌纲、γ-变形杆菌纲、拟杆菌和放线菌。α-变形杆菌纲在两种藻的藻际环境中占据优势，其中红杆菌科是最为常见的科，中肋骨条藻的藻际细菌比海洋卡盾藻更为多样化。海洋卡盾藻生长后期细菌密度大幅度上升，可能导致了藻细胞的衰亡。中肋骨条藻相关细菌中有一株对旋链角毛藻的生长具有明显抑制作用，而大部分海洋卡盾藻相关细菌对角毛藻的生长具有抑制作用。本研究结果说明海洋卡盾藻的藻际细菌也许对其与硅藻的种间竞争中具有一定作用。 相似文献
12.
The effects of temperature and different forms of nutrients on Chattonella marina growth have been investigated in strains isolated from the Daya Bay,the South China Sea.The strain of C.marina preferred high temperatures, with an optimal temperature of 25°C,and 18 °C was the minimum for its survival.Higher cell number and growth rate were obtained in high nitrogen and phosphorus concentrations (500 μ g/L, 74 μ g/L) than under nutrient limitation.Nitrogen influenced the growth most, as the specific growth rate and maximum cell density were lower in nitrogen-limited cultures than noted under phosphorus limitation or under limitation from both.C.marina was capable of using many kinds of organic nitrogen sources including L-serine (L-Ser),glycine (Gly),alanine (Ala),L-threonine (L-Thr), glutamic acid (Glu) and urea, but could not utilize uric acid.Various forms of organic phosphorus compound such as glucose-6-phosphate (G6P),sodium glycerophosphate (GYP),adenosine triphosphate (ATP),adenosine monophosphate (AMP),cytidine monophosphate (CMP),guanosine monophosphate (GMP),uridine monophosphate (UMP),4-nitrophenylphosphate (NPP) and triethyl phosphate (TEP) supported the growth as well. Algal cells had the ability to sustain growth under nitrogen-and/or phosphorus-free conditions particularly under phosphorus depleted condition.These results led to the hypothesis that high loading of nitrogen has played an important role in frequent C.marina blooms in the past decade,and its capability for utilization of diverse forms of organic nutrients and growth in low nutrient conditions make this species a likely recurrent dominant in the Daya Bay phytoplankton assemblages,visible as 相似文献
13.
本研究以海洋微藻——赤潮藻海洋卡盾藻(Chattonella marina)与饵料藻青岛大扁藻(Platymonas helgolandica var.tsingtaoensis)为研究对象,采用单培养和共培养的方法,研究二者间的竞争关系,并在此基础上研究海洋卡盾藻去藻过滤液和藻细胞裂解液对青岛大扁藻的化感作用,同时进一步探讨两种海洋微藻间的化感作用对UV-B辐射增强的响应。结果显示:共培养条件下,海洋卡盾藻在2个高浓度下对青岛大扁藻的生长产生显著抑制(P0.05);海洋卡盾藻去藻过滤液和藻细胞裂解液对青岛大扁藻的生长也具有显著抑制作用(P0.05),且藻细胞裂解液的抑制作用更强,说明海洋卡盾藻对青岛大扁藻产生化感作用,且通过细胞间直接接触传递的化感物质多于通过介质传递的。不同密度比例的2种藻共培养组用UV-B辐射(2.16J/m2)处理后,海洋卡盾藻对青岛大扁藻生长的化感作用有所减弱。 相似文献
14.
全球气候变化导致海洋氧含量降低,海水低氧胁迫对海洋无脊椎动物的生长、发育和繁殖造成了严重的威胁。以海洋线虫Litoditis marina为实验对象,观察了其在不同氧浓度(21%、3%、1%和0.5%)条件下的生长发育速率,并对不同氧浓度条件下的L1幼虫样品进行了转录组测序和分析。实验结果表明,当环境氧浓度从21%下降至3%时, L. marina的发育成熟速度明显加快,进一步下降至1%时,产卵时间延长并和21%氧浓度接近,但当氧浓度为0.5%时,L.marina的产卵时间显著延迟。比较转录组分析表明,相比于21%氧浓度环境, 3%、1%和0.5%低氧条件下L. marina的糖酵解、糖异生、硫代谢和线粒体碳代谢等通路相关基因的表达显著上调;而寿命调控通路、细胞色素P450代谢通路和ABC转运蛋白相关基因的表达显著下调。研究结果发现的海洋线虫应对氧浓度胁迫的基因表达变化模式,为深入理解海洋无脊椎动物应答低氧胁迫分子机制提供了重要参考。 相似文献
15.
The neritid Smaragdia viridis represents the only known native marine mollusc that feeds on seagrass tissues in the European coasts, displaying a strong association with the seagrasses Cymodocea nodosa and Zostera marina in southern Spain. Seasonal dynamics, shell and radular morphology, growth and feeding of this gastropod have been studied in relation to each seagrass species for contrasting trends resulting from a different type of substrate and food source. In both seagrass species, stable populations of this gastropod occur at similar densities and displaying similar growth rates. Nevertheless shells of individuals from C. nodosa are narrower than those from Z. marina and some differences, possibly a consequence of increased wearing on C. nodosa, were noted amongst the radulae. In C. nodosa, a pre-ingestive selection for young epidermal tissues occurs as it was previously observed in Z. marina. The ingestion rate is higher in C. nodosa than in Z. marina but the absorption of ingested tissues is lower in the former. If both seagrasses are present, most individuals ingested preferentially Z. marina rather than C. nodosa, probably due to the lower digestibility of the epidermal tissues in the latter. Seagrass beds, especially those of Z. marina, are suffering a strong regression in southern Spain and the presence of stable populations of this neritid may be restricted to other declining seagrass species in the area. 相似文献
16.
We have previously shown that largemouth bass (Micropterus salmoides) has a remarkable ability to conjugate 4-hydroxy-2-nonenal (4HNE), a mutagenic and cytotoxic α,β-unsaturated aldehyde produced during the peroxidation of lipids. In addition, we have isolated a glutathione S-transferase cDNA (bass GSTA) that encodes a recombinant protein which is highly active in 4HNE conjugation and structurally similar to plaice (Pleuronectes platessa) GSTA. In the present study, HPLC-GST subunit analysis revealed the presence of at least two major GST isoforms in bass liver, with one peak constituting 80% of the total bass liver GST protein. Liquid chromatography mass spectrometry (LC–MS) and electrospray ionization analysis of the major bass GST subunit yielded a molecular weight of 26,396 kDa. Endo-proteinase Lys-C digestion and Edman degradation protein sequencing of this GST peak demonstrated that this protein was encoded by bass GSTA. Analysis of genomic DNA fragments isolated by nested PCR indicated the presence of a GST gene cluster in bass liver that contained GSTA, and was similar to a GST gene cluster characterized by Leaver et al., in plaice. Collectively, our data indicates the presence of a major GST in bass liver involved in the protection against oxidative stress. This GST is part of a gene cluster that may be conserved in certain freshwater and marine fish. 相似文献
17.
Vast declines in Zostera marina seagrass beds demand effective methods of rehabilitation. In this study, we developed a practical method by reducing salinity to induce seed germination followed with recovering salinity to facilitate seedling production of Z. marina. The results showed that Z. marina seeds collected from natural seawater(salinity 30) were induced to germinate at reduced salinities. Percent germination(GR) was higher and mean-time-to-germinate(MTG) was shorter at lower salinities. The highest GR and shortest MTG occurred at salinity 0(deionized freshwater). After germination in freshwater, seeds could develop into seedlings at salinities5–30 and continue the growth. Viability or development of germinated seeds was not significantly different during the 40 d of post-germination incubation at salinities 5–15 after 1–20 d of germination in freshwater. However,during the process of translating germinated seeds from salinity 0 and 5 to salinity 30, reducing the gradients of post-germination acclimation facilitated more seeds forming seedlings in less time. On average, after 60 d of static incubation, including 20 d in freshwater for germination followed with immediate shift to salinity 5 and increasing to salinity 30 at increment of 5 every two days until cultivation at constant salinity 30, 33% of Z. marina seeds produced healthy seedlings. The results indicate that the salinity-manipulation based method of artificial germination and seedling production is practical and effective in supporting rehabilitation of Z. marina bed. 相似文献
18.
以海水青鳉(Oryzias melastigma)胚胎为研究对象,比较了120#燃料油分散液(water-accommodated fractions,WAFs)与乳化液(biologically enhanced water-accommodated fractions,BE-WAFs)的急性毒性效应,并研究了不同浓度(40、100、250 mg/L)下WAFs、BE-WAFs对胚胎内超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽硫转移酶(GST)活性的影响。结果表明:在受到石油烃的氧化胁迫后,海水青鳉胚胎内3种抗氧化酶活性变化明显。随着石油烃浓度的升高和暴露时间的延长,3种酶表现出程度不同的诱导效应和抑制效应。其中受石油烃污染影响最为明显的为SOD酶;而GST酶则对消油剂单独暴露表现较为敏感。实验证明,海水青鳉体内SOD酶活性对石油烃污染反应最为敏感,适合作为监测石油烃污染程度的生物标志物。 相似文献
19.
A comparison of growth patterns between non‐indigenous Halophila nipponica and the native sympatric Zostera marina on the southern coast of the Korean peninsula 
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下载免费PDF全文 The growth dynamics of two co‐occurring seagrass species, Zostera marina and Halophila nipponica, were examined on the southern coast of the Korean peninsula. Zostera marina is a native dominant seagrass species in Korean coastal waters, whereas H. nipponica is a non‐native tropical and subtropical species that has extended its distributional range to the temperate coastal areas of Korea. To examine the differences in the growth dynamics of H. nipponica and Z. marina, their morphology, density, productivity and biomass, as well as local environmental conditions, were monitored monthly from January 2008 to July 2009. Underwater irradiance at the study site was the highest in April 2009 and the lowest in January 2008. Water temperature ranged from 10.4°C in January 2009 to 24.8°C in September 2008. Significant differences in growth dynamics were observed between the species, due to the effect of water temperature at the study site. Density and areal productivity were the highest in April 2008 and June 2008, respectively, for Z. marina but the highest in July 2008 for H. nipponica. Leaf size, shoot height and shoot weight were the highest in July 2008 for Z. marina but the highest in August 2008 or September 2008 for H. nipponica. The productivity of both species was strongly correlated with water temperature at the study site. However, the productivity of these species was not strongly correlated with underwater irradiance or the nutrient availability of either the water column or sediment pore water. Zostera marina exhibited the ecological characteristics of a temperate seagrass, whereas H. nipponica retained the features of a subtropical/tropical seagrass, even after adapting to the temperate coastal waters of Korea. 相似文献