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1.
珊瑚荧光的古降水记录 总被引：3，自引：0，他引：3
珊瑚作为热带海洋气候环境的信息载体，不仅记录了过去海洋信息，也记录了陆源环境信息。Isdale于1984年在《Nature》杂志上发表论文阐明珊瑚的黄绿荧光记录了Burdekin河的径流量变化以后，国际上对珊瑚荧光的研究逐渐发展起来，并取得了不少成果。研究表明，利用珊瑚荧光所提供的信息，可以重现过去大陆沿海的降雨变化情况、干旱或洪涝的变化旋回及入海河流的径流量变化。这对研究并重建过去气候环境、预报未来的气候变化趋势有着重要的意义。本文评述了国外对珊瑚荧光的研究进展、报道了本实验室进行了初步工作，同时，对珊瑚荧光作为环境地球化学新的代用指标所潜在的应用前景进行了讨论。 相似文献
2.
盐胁迫对塔胞藻生长及叶绿素荧光动力学的影响 总被引：12，自引：2，他引：12
利用调制式叶绿素荧光仪(Water-PAM)研究了盐度(1~120)胁迫不同时间(12,24,48 h)后,塔胞藻生长及叶绿素荧光动力学的变化。测定的主要参数有:PSⅡ的最大光能转化效率(Fv/Fm)、PSⅡ的潜在活性(Fv/Fo)、PSⅡ的实际光能转化效率(ΦPSⅡ=yield)、光合电子传递效率(ETR)、光化学淬灭(qP)和非光化学淬灭(NPQ)。结果表明:在本实验条件下,塔胞藻生长和进行光合作用的最适盐度为20。高盐胁迫使塔胞藻的荧光参数Fv/Fm,Fv/Fo,ΦPSⅡ,ETR,qP均明显降低,NPQ则先升高后降低,叶绿素含量和细胞密度也显著降低。还对盐胁迫下塔胞藻的响应机制以及叶绿素荧光技术在筛选耐盐微藻品种中的应用进行了初步探讨。 相似文献
3.
4.
造血激素(astakine)是一种具有促进造血组织细胞分化和增殖作用的甲壳动物细胞因子,参与甲壳动物的造血活动,对于只依赖于非特异性免疫的甲壳动物抗感染能力有重要的意义。本实验室前期成功克隆凡纳滨对虾造血激素(LvAST)的基因Lvast。为了进一步了解其功能,本文通过实时荧光定量PCR技术检测了Lvast表达的组织分布,同时还用Dlight标记抗LvAST抗体进行了LvAST在对虾细胞和组织中的免疫荧光定位分析。荧光定量PCR测定结果说明,Lvast主要在肝胰腺、鳃和肌肉中大量表达,而淋巴器官和血淋巴细胞中表达量较低;免疫荧光结果显示,LvAST可同时存在于血淋巴细胞内和血淋巴细胞膜表面,不同的血淋巴细胞表面的LvAST分布呈现出明显差异,可能具有重要的血细胞分类意义。LvAST蛋白在肝胰腺、鳃、肌肉、淋巴器官等组织中均有分布,并且肝胰腺组织中分布较多,淋巴器官组织中分布较少。 相似文献
5.
高温胁迫对三角褐指藻和纤细角毛藻叶绿素荧光动力学的影响 总被引：6，自引：2，他引：6
研究高温胁迫(35~50℃)对三角褐指藻和纤细角毛藻叶绿素荧光动力学的影响。利用调制式叶绿素荧光仪(Wa-ter-PAM)测定了:PSⅡ的最大光能转化效率(Fv/Fm);PSⅡ的潜在活性(Fv/Fo);PSⅡ的实际光能转化效率(ΦPSⅡ=yield);光合电子传递效率(ETR);光化学淬灭(qP)和非光化学淬灭(NPQ)等主要参数。结果表明,与对照组相比,高温胁迫下2种硅藻的叶绿素荧光参数Fv/Fm,Fv/Fo,ΦPSⅡ,ETR和qP均明显降低,并且随着胁迫温度的升高,胁迫时间的延长,下降幅度也逐步增大;NPQ则先升高后下降。另外,还对高温胁迫下2种硅藻的响应机制以及叶绿素荧光技术在筛选耐高温微藻品系中的应用进行了初步探讨。 相似文献
6.
锦鲤疱疹病毒实时荧光定量PCR检测方法的建立及应用 总被引：2，自引：0，他引：2
研究建立并完善了Taqman实时荧光定量PCR检测锦鲤疱疹病毒（KHV）的方法。首先通过选取KHV病毒TK基因的保守序列（GenBank AB182940）,利用PRIMER EXPRESS 2.0设计引物和探针。其中Taqman探针的5’端标记FAM,3’端标记TAMRA。然后利用梯度稀释的阳性样品克隆质粒进行定量PCR反应,制作标准曲线,得到病毒拷贝数与Ct值的关系为：Ct=-3.45 lgX＋42.73（相关系数R2=0.989）。通过试验检测得到实时荧光定量PCR对KHV的灵敏度为32个病毒核酸拷贝数,同时,设计的引物和探针对于鱼类细胞系和其它鱼类病毒没有扩增反应,表现出较好的特异性。实验结果表明,实时荧光定量PCR检测KHV的方法,具有特异性好、灵敏度高的特点,可以缩短检测时间,提高检测速度,非常适合口岸进出口检验检疫的要求。 相似文献
7.
中国对虾肝胰脏细小病毒（ｈｅｐａｔｏｐａｎｃｒｅａｔｉｃｐａｒｖｏｖｉｒｕｓｄｉｓｅａｓｅ,ＨＰＶＤ）是一种广泛流行于中国对虾中的危害性较大的疾病。由于该病没有特异的肉眼症状,因此早期、快速诊断方法的研究就十分重要。作者曾完成了ＳＰＡ协同凝集试验法和免疫金银染色法的诊断研究。本文用直接荧光抗体法进行研究,观察其诊断效果。结果是,将抗ＨＰＶ的荧光抗体滴加到对虾肝胰脏组织涂片以后,在某些样品的肝胰脏上皮细胞中出现了圆形、椭圆形,大小６～１３μｍ的黄绿色荧光物。经比较,该荧光物的大小和形状与同一样品病理组织切片上经Ｈ－Ｅ染色后上皮细胞中出现的ＨＰＶ包涵体是一致的。由此认为,这些存在于肝胰脏上皮细胞内的荧光物是ＨＰＶ包涵体,而直接荧光抗体法用于诊断中国对虾ＨＰＶ是有效可行的。 相似文献
8.
三维荧光光谱及平行因子分析法在CDOM研究中的应用 总被引：7，自引：0，他引：7
文章对有色可溶性有机物(Chromophoric dissolved organic matter:CDOM)三维荧光特性的研究进行了综述,指出了三维荧光光谱分析在水体CDOM特性研究中存在的优缺点;阐述了平行因子分析法在水体CDOM研究中的具体应用程序及运用此方法识别得到的水体组分;汇总了当前表征CDOM荧光特性的常用指标;总结了国内外在三维荧光光谱研究水体CDOM特性方面的进展,详述了不同类型水体中CDOM的组分特性、生物地球化学循环的研究热点以及影响CDOM三维荧光光谱特性的一些主要因素;最后,对三维荧光光谱技术在未来的发展及应用进行了展望。 相似文献
9.
造血激素（astakine）是一种具有促进造血组织细胞分化和增殖作用的甲壳动物细胞因子,参与甲壳动物的造血活动,对于只依赖于非特异性免疫的甲壳动物抗感染能力有重要的意义。本实验室前期成功克隆凡纳滨对虾造血激素（LvAST）的基因Lvast。为了进一步了解其功能,本文通过实时荧光定量PCR技术检测了Lvast表达的组织分布,同时还用Dlight标记抗LvAST抗体进行了LvAST在对虾细胞和组织中的免疫荧光定位分析。荧光定量PCR测定结果说明,Lvast主要在肝胰腺、鳃和肌肉中大量表达,而淋巴器官和血淋巴细胞中表达量较低;免疫荧光结果显示,LvAST可同时存在于血淋巴细胞内和血淋巴细胞膜表面,不同的血淋巴细胞表面的LvAST分布呈现出明显差异,可能具有重要的血细胞分类意义。LvAST的蛋白在肝胰腺、鳃、肌肉、淋巴器官等组织中均有分布,并且肝胰腺组织中分布较多,淋巴器官组织中分布较少。 相似文献
10.
利用SYBR荧光定量PCR技术，制备用于花鲈（Lateolabrax japonicus）PPARα基因实时荧光定量PCR检测的质粒标准品．通过PCR扩增出目的片断344-bp，纯化后连接至pMDI8-T载体，转化宿主菌E．coli DH5α．通过PCR鉴定、双酶切鉴定和测序分析后抽提重组质粒，测定其拷贝浓度，10倍梯度稀释成标准品模板10^8～10^4 copy／mm^3，进行荧光定量PCR分析．结果显示，循环阈值（Ct）与起始模板量的对数值之间有着良好的线性关系． 相似文献
11.
《African Journal of Marine Science》2013,35(4):439-447
Coral cell aggregates (tissue balls) from four species (Acropora muricata, Fungia repanda, Pavona cactus and Pocillopora damicornis) were used as an indicator to investigate the effects on the corals of thermal stress and of chemical extracts from three sponges (Adocia sp., Haliclona sp. and Lissodendoryx sp.) and one ascidian (Didemnum molle). The formation and disintegration of tissue balls were studied through exposure to a temperature range of 23–30 °C at time intervals of 0–90 min, and to sponge and ascidian crude extracts at concentrations of 50–200 µg ml?1 at temperatures of 23 and 30 °C and at time intervals of 10, 60 and 120 min. The negative effect of temperature on overall tissue ball density (number per cm2 of coral surface) was greatest at higher temperatures (28 and 30 °C) but varied among coral species. Tissue balls of P. damicornis were the most robust whereas those of A. muricata were the most sensitive. High concentrations of extracts of Adocia sp., Haliclona sp. and Lissodendoryx sp. generally inhibited the formation of tissue balls or caused their disintegration, or both, most markedly at 30 °C. Adocia sp. induced the least negative effects and Haliclona sp. the most. No tissue balls were formed in the presence of D. molle extracts (50 and 100 µg ml?1), indicating a high level of interference with tissue ball formation. The differential susceptibility to thermal and chemical stressors exhibited by the corals under study have possible implications for the interactions of the corals with other sedentary reef organisms under climate change-driven ocean warming. 相似文献
12.
Kaori Ohki 《Journal of Oceanography》2008,64(2):211-216
The nitrogenase activities of cyanobacteria of the genus Trichodesmium are strictly light-dependent, although they do not develop heterocysts. Recently, the development of heterocyst-equivalent
cells (diazocytes) was suggested in Trichodesmium spp. However, no cells with a similar appearance to diazocytes could be found in Trichodesmium sp. NIBB1067. An immunocytochemical analysis of nitrogenase in individual cells was performed using polyclonal antibodies
generated from DNA fragments of genes encoding the Fe-protein and the α-and the β-subunit of the MoFe-protein of nitrogenase of Trichodesmium sp. NIBB1067. Visualization of the antibody binding was carried out using a horseradish peroxidase-conjugated secondary antibody
and a chromogenic substrate, 3,3′-diaminobenzidine, to avoid the masking effects caused by the bright autofluorescence emitted
by Trichodesmium cells. Nitrogenase proteins were detected in almost all the cells (always higher than 95% of total cells) grown under nitrogen-limited
conditions. These results indicate that Trichodesmium sp. NIBB1067 does not differentiate heterocyst-equivalent cells. 相似文献
13.
采用电感耦合等离子体质谱仪测定了厦金海域8种珊瑚中Cr、Mn、Co、Ni、Cu、Zn、As、Cd、Sn、Sb、Pb重金属的含量,通过数据处理、主成分分析方法,分析了重金属分布特征和其主要来源。采用单因子污染指数法对珊瑚重金属的污染水平进行了评价。结果表明,其平均浓度水平从大到小依次为:ZnMnSnCrCuAsNiPbSbCdCo。在8种珊瑚中,星柳珊瑚(Astrogrogia sp.)、等柳珊瑚(Paris fruticosa)、Paraplexaura sp.的重金属含量较高,花柳珊瑚(Anthogorgia sp.)和Guaiagorgia anas的含量较低。台湾海域珊瑚中Cu、Zn、Pb、Ni的含量、委内瑞拉海域珊瑚中Zn、Pb、Ni的含量远高于厦金海域珊瑚体内相同重金属含量,大堡礁珊瑚中Cu含量较厦金海域的略高。通过相关性分析发现,Cr、Co、Ni、Zn和Sn的种间差异较为显著。根据主成分分析,厦金海域珊瑚体内重金属元素可能的污染来源有:农业污染、港口生活污水和工业污水的排放、船舶油漆、涂料侵蚀、电镀工业。单因子污染指数法评价结果表明,6种重金属元素中,大佰屿、白哈礁和角屿的主要污染物是Mn。白哈礁、大佰屿站位的珊瑚体内重金属Mn处于重度污染水平,角屿站位的处于中度污染水平。 相似文献
14.
海南岛西北部海域珊瑚礁造礁石珊瑚种类组成与分布 总被引：1，自引：0，他引：1
调查了海南岛西北部海域造礁石珊瑚种类的多样性及分布.结果表明:共发现50种造礁石珊瑚和1种多孔螅.海南岛西北部造礁石珊瑚优势种为澄黄滨珊瑚(Porites lutea)和丛生盔形珊瑚(Galaxea fascicularis),与历史资料相比优势种发生明显变化;海南岛西北部海域造礁石珊瑚覆盖率急剧下降,是由自然因素和人为活动共同造成;海南岛西北部海域是北部湾、琼州海峡和南海的重要交汇点,可能是造礁石珊瑚幼虫扩散的重要通道,对华南沿岸造礁石珊瑚资源自然恢复起到重要作用.因此,未来的海洋管理应该加强对珊瑚礁的保护力度,开发利用与环境保护并重,这样才能有效保护海南岛西北部海域的珊瑚礁. 相似文献
15.
Sven Zea 《Marine Ecology》2011,32(2):162-173
The Caribbean sponge Cliona delitrix is among the strongest reef space competitors; it is able to overpower entire coral heads by undermining coral polyps. It has become abundant in reefs exposed to organic pollution, such as San Andrés Island, Colombia, SW Caribbean. Forty‐four sponge‐colonized coral colonies were followed‐up for 13 months to establish the circumstances and the speed at which this sponge advances laterally into live coral tissue and the coral tissue retreats. Cliona delitrix presence and abundance was recorded at seven stations to interpret current reef space and coral species colonization trends. The spread of C. delitrix on a coral colony was preceded by a band of dead coral a few millimeters to several centimeters wide. However, the sponge was directly responsible for coral death only when live coral tissue was within about 2 cm distance; coral death became sponge advance‐independent at greater distances, being indirectly dependent on other conditions that tend to accelerate its retreat. Cliona delitrix advanced fastest into recently killed clean coral calices; however, sponge spread slowed down when these became colonized by algae. The lateral advance of C. delitrix was slower than other Cliona spp. encrusting excavating sponges, probably owing to the greater depth of its excavation into the substratum. Cliona delitrix prefers elevated portions of massive corals, apparently settling on recently dead areas. It currently inhabits 6–9% of colonies in reefs bordering San Andrés. It was found more frequently in Siderastrea siderea (the most abundant local massive coral), which is apparently more susceptible to tissue mortality than other corals. Current massive coral mortality caused by C. delitrix could initially change the relative proportions of coral species and in the long‐term favor foliose and branching corals. 相似文献
16.
在三亚湾环境下四种方法在五种造礁石珊瑚上移植效果的比较 总被引：2，自引：0，他引：2
珊瑚移植一直被认为是增加退化珊瑚礁上珊瑚数量的重要手段之一。为了调查多种珊瑚移植方法和不同珊瑚种类的移植效果,我们选择了已严重退化并仍面临着人类和自然环境胁迫的三亚鹿回头珊瑚礁作为移植地,对5种珊瑚共902个断枝利用4种方法进行了移植。在移植后的10个月,移植珊瑚的存活率为45.5%。移植方法对于不同珊瑚种类具有不同效果,但没有一种方法能够对所有珊瑚的移植效果产生促进作用。虽然对于叶状蔷薇珊瑚（Montipora foliosa）和风信子鹿角珊瑚（Acropora hyacinthus）来说,适合的移植方法能够减缓其死亡速率,但并不能改变其死亡趋势。叶状蔷薇珊瑚和风信子鹿角珊瑚的移植个体呈现出高死亡率和明显的存活组织面积下降,而扁枝滨珊瑚（Porites andrewsi）和丛生盔形珊瑚（Galaxea fascicularis）死亡率和组织部分死亡率则优于前两者。扁枝滨珊瑚和丛生盔形珊瑚仅在一种移植方法中出现了存活组织面积明显增长。鹿角杯形珊瑚（Pocillopora damicornis）是移植珊瑚中唯一一种在所有移植方法上都呈现珊瑚平均存活面积增长的种类。实验结果说明在受到高度胁迫的海域进行珊瑚移植很难取得满意效果,珊瑚种类的选择对胁迫环境下的珊瑚移植效果具有决定性影响,而移植方法只能在部分程度上改善移植效果,但无法弥补鹿回头环境压力对敏感种类胁迫造成的影响。在鹿回头珊瑚礁需首先治理对珊瑚造成胁迫的因子,再进行珊瑚移植,并应优先考虑移植环境耐受性高的珊瑚种类。 相似文献
17.
Assessment of the effectiveness of natural coral fragmentation as a dispersal mechanism for coral reef‐boring sponges 
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下载免费PDF全文 Eastern Pacific reefs are mostly made up of interlocking coral branches of Pocillopora, which are easily broken by physical forces associated with heavy swells and winds. In this study we investigated the potential of these coral fragments to enable propagation of boring sponges. For this, we quantified the frequency of occurrence and diversity of boring sponges in fragments of corals recently trapped among the branches of live colonies, and later tested the hypothesis that these sponges colonize new branches of corals. Nearly 80% of the coral colonies investigated had coral fragments among their branches, and 69% of these coral fragments contained boring sponges (11 species), some of these sponges in reproduction (23% of them carried oocytes). To test whether sponges inhabiting coral fragments could colonize new branching corals we transplanted them to healthy branches, and to branches whose living tissue was mechanically eliminated to simulate damage produced by grazing and death after bleaching and other causes of coral tissue mortality. All the transplanted coral fragments cemented to each new colony by means of calcification, and of the three sponge species tested (Cliona vermifera, Cliona tropicalis and Thoosa mismalolli) only C. vermifera was able to colonize both new living branches (26.9%) and cleaned branches (65.5%). The apparent capability of C. vermifera to colonize by direct contact may be another key ability of this species to maintain high frequency of occurrence in Pacific coral reefs. However, although C. tropicalis and T. mismalolli were not able to colonize new coral substrata by direct contact, coral fragments have the potential to contribute to local persistence of these sponges and to their dispersal, both by asexual (fragments) and sexual means (transport of sexual products). The present findings may partly explain the current increase of excavating sponges on deteriorating reefs with a large availability of dead branching corals. 相似文献
18.
Pollution, turbidity and coral bleaching history, as well as coral diversity, vary along the Tanzanian coastline. Prior to this study, it was not known whether exposure to such environmental variation might have influenced the diversity and distribution of Symbiodinium along this coastline. Such information can provide insight into whether Tanzanian reef-building corals develop adaptation to current trends of climate change. Here, 10 reef-building coral samples were collected from different reefs along the Tanzanian coast with different micro-environments and bleaching histories. The ITS-2 region of ribosomal DNA was employed in the characterisation of Symbiodinium harboured by reef-building corals. DGGE fingerprints and DNA sequences showed that most coral species host a single Symbiodinium type, which is maintained throughout the coast regardless of local environmental differences. We present polymorphic symbioses in Acropora spp., Millepora sp. and Galaxea fascicularis in mainly turbid and warm environments as a sign of adaptation to harsh conditions. However, such adaptation may not provide marked resistance to bleaching because Acropora is a bleaching-susceptible genus. 相似文献
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Concurrent imaging of chlorophyll fluorescence,Chlorophyll a content and green fluorescent proteins‐like proteins of symbiotic cnidarians 下载免费PDF全文
下载免费PDF全文 Miguel Costa Leal Bruno Jesus João Ezequiel Ricardo Calado Rui Jorge Miranda Rocha Paulo Cartaxana João Serôdio 《Marine Ecology》2015,36(3):572-584
Research on photosynthetic cnidarians has been mainly focused on the symbiosis established between the cnidarian host and its dinoflagellates endosymbionts from genus Symbiodinium. Despite the potential of imaging techniques for assessing the spatial distribution of key parameters of cnidarian photobiology, such as photochemical activity, chlorophyll a content or green fluorescent proteins (GFPs), to our best knowledge, no study has ever attempted to simultaneous map these three features. In this study, we developed a modified imaging pulse amplitude fluorometer by applying excitation light of different wavelengths and selectively detecting short spectral bands through bandpass filters. The imaging system was used to sequentially excite and quantify chlorophyll variable fluorescence (maximum quantum yield of photosystem II, Fv/Fm), Chl a content (normalized difference vegetation index) and relative content of GFPs. The spatial distribution of these photophysiological parameters was mapped both horizontally, across the surface of the soft corals Sarcophyton cf. glaucum and Sinularia flexibilis and the zoanthid Protopalythoa sp., and vertically, throughout a vertical section of S. cf. glaucum. Results showed bleached areas within each individual coral colony and registered photophysiological changes with S. cf. glaucum tissue depth. Analysis of Protopalythoa sp. polyps’ expansion revealed differential surface patterns of NDVI and GFP concentration, and a negative relation between these latter parameters within each polyp. This novel non‐invasive approach allowed a high‐resolution characterization of the spatial relationship between these key parameters through the analysis of image information on a pixel‐by‐pixel basis, which has great potential for investigating the physiological state of symbiotic associations. 相似文献
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Studying interactions between excavating sponges and massive corals by the use of hybrid cores 下载免费PDF全文
下载免费PDF全文 James K. H. Fang Robert A. B. Mason Christine H. L. Schönberg Ove Hoegh‐Guldberg Sophie Dove 《Marine Ecology》2017,38(1)
Excavating sponges often compete with reef‐building corals. To study sponge–coral interactions, we devised a design of hybrid cores that allows sponges and corals to be arranged side by side with similar size and shape, mimicking the situation of neighbouring organisms. Compared to earlier methods that attached sponge cores onto coral surfaces, hybrid cores provide an opportunity to study organism interactions under conditions more equal to the interacting partners. The use of hybrid cores was demonstrated for the excavating sponge Cliona orientalis and the massive coral Porites, which commonly interact on the Great Barrier Reef. Cliona orientalis and massive Porites were cut into half‐moon shaped explants and combined as hybrid cores under replicate conditions. After 90 days in an aquarium setting, positive growth of Cl. orientalis along with net bioerosion were observed in sponge control cores that combined Cl. orientalis with blank substrate. However, when Cl. orientalis and massive Porites were in contact in interaction cores, the sponge displayed negative growth and undetectable bioerosion, and was slightly overgrown by the coral. Cliona orientalis may have developed tissue extension beneath the living coral tissue, but growth and net calcification rates of massive Porites were apparently not affected by Cl. orientalis when comparing the interaction cores to coral control cores that combined massive Porites with blank substrate. Overall, the present work demonstrated that hybrid cores can be used to generate conditions suitable for studying sponge–coral interactions in the laboratory, which can also be applied in the field. 相似文献