用于单一藻细胞PCR扩增反应的样品保存方法比较     

李萍  于仁成  唐祥海  周名江 《海洋科学》2008,32(6):41-45

用室内培养的塔玛亚历山大藻(Alexandrium tamarense ATHK藻株)作为实验对象,分别选择了5%福尔马林固定后常温保存、95%乙醇固定后常温保存、-20℃冷冻保存、鲁哥氏液(Lugols solution)固定后常温保存等方法,在5,15,30,60 d后对保存的样品进行单细胞PCR反应,并与新鲜样品进行比较。实验结果表明,用95%乙醇保存、-20℃冷冻保存、鲁哥氏液保存的样品在60 d后仍可扩增出目标条带,与新鲜样品没有差别,但是样品中的藻细胞形态有一些改变;而以5%福尔马林固定保存的样品只能在5 d后扩增出目标条带,但藻细胞形态比较完好。因此,对用于单细胞PCR实验的微藻样品,短期内(不多于5 d)可以采用福尔马林保存,而需要长期保存的样品,应当采用乙醇或鲁哥氏液固定,或者采用-20℃冷冻保存的方法。  相似文献   

Characteristics of phytoplankton community structure during and after a bloom of the dinoflagellate Scrippsiella trochoidea by HPLC pigment analysis     

Chun-kwan Wong  Chong-kim Wong 《中国海洋大学学报(英文版)》2009,8(2):141-149

A bloom of the dinoflagellate Scrippsiella trochoidea was detected for the first time in inner Tolo Harbor, Hong Kong in 2 000. Water samples were collected at eight stations along a transect passing through a red tide patch for microscopic analysis of phytoplankton composition and high-performance liquid chromatography (HPLC) analysis of phytoplankton pigments. During the bloom, the density of dinoflagellates was 1.1×10⁶ cells L⁻¹ within the patch and 8.6×10⁵ cells L⁻¹ outside the patch where the phytoplankton community was dominated by diatoms. After the bloom the S. trochoidea began to decrease in density and was replaced by diatoms as the dominating bloom-causing organisms at all stations, and the density of dinoflagellates at most stations was less than 1.0 × 10⁶ cells L⁻¹. The status of S. trochoidea as the causative species of the bloom was indicated by the presence of peridinin, the marker pigment for dinoflagellates. The shift from dinoflagellates to diatoms was marked by the decline of peridinin and the prevalence of fucoxanthin. Phytoplankton pigment markers also revealed the presence of other minor phytoplankton assemblages such as cryptomonads and blue-green algal.  相似文献   

Latitudinally different responses of Tethyan shoal‐water carbonate systems to the Early Aptian oceanic anoxic event (OAE 1a)     

STEFAN HUCK  NIELS RAMEIL  TVRTKO KORBAR  ULRICH HEIMHOFER  THOMAS D. WIECZOREK  ADRIAN IMMENHAUSER 《Sedimentology》2010,57(7):1585-1614

Ocean‐wide anoxic events represent intensively investigated anomalies in the global carbon cycle. Most previous research has focussed on hemipelagic and pelagic settings and on the relationship between black‐shale deposition and carbon‐isotope excursions. The study of ocean‐wide anoxic events and coeval shallow‐water settings is now increasingly seen as an interesting complementary approach, but one that is not without problems. Whereas platform drowning characterizes the Early Aptian of the northern Tethyan margin, Lithocodium–Bacinella‐rich facies and ongoing shoal‐water sedimentation at the southern Tethyan margin (Oman) bears important information on potential causes of carbon‐cycle perturbations. The present paper seeks to test the supra‐regional relevance of the Oman data by investigating coeval central Tethyan limestones. Three Lower Aptian shoal‐water sections in Istria (Croatia), deposited on the isolated Adriatic Carbonate Platform, are investigated applying chemostratigraphy (carbon and strontium) and detailed sedimentological analysis. The focus is on peritidal to lagoonal facies characterized by mass occurrences of Lithocodium–Bacinella, an enigmatic microencruster community. Lithocodium–Bacinella facies occurs predominantly in layers ranging from one to several centimetres in stratigraphic thickness, with several layers merging to metre‐thick packages. Growth fabrics within the layers include oncoidal morphotypes, lumps, interconnected patches and columns, layers and rare nodular to massive bindstone facies. These growth patterns show a remarkable regional extent and consistency over study sites distributed several kilometres apart. This widespread distribution suggests that specific Lithocodium–Bacinella morphotypes might serve as regional stratigraphic markers. The high‐resolution carbon‐isotope chemostratigraphy presented here is based on pristine rudist shells and matrix micrite samples and calibrated against strontium‐isotope data obtained from screened rudist low‐Mg calcite. The chemostratigraphic data are consistent with existing biostratigraphic data and place the studied strata at the onset of Early Aptian oceanic anoxic event 1a. Moreover, results indicate the near‐coeval nature of Lithocodium–Bacinella bloom facies in Istria and Oman. The outcomes of this study point to latitudinally different responses of Tethyan shoal‐water carbonate systems (platform drowning versus Lithocodium–Bacinella blooms) to the ocean‐wide anoxic event 1a.  相似文献   

不同温度下抑食金球藻、中肋骨条藻和海洋卡盾藻间的相互作用     

郑承志  左丽明  马旺  朱琴  王火火  吕颂辉  陈亨  黄凯旋 《热带海洋学报》2021,40(3):124-131

本文选取抑食金球藻(Aureococcus anophagefferens)、中肋骨条藻(Skeletonema costatum)和海洋卡盾藻(Chattonella marina)三种藻在20℃和25℃下进行单种、两种或三种藻间的培养实验, 探究在不同温度下藻种间的相互作用和竞争优势。单种培养结果显示抑食金球藻和中肋骨条藻对温度25℃敏感, 其环境容量(K)被显著降低; 而海洋卡盾藻的內禀增长率(r)在25℃下显著升高, 但K保持不变。在共培养中, 海洋卡盾藻在20℃下因抑食金球藻添加致死, 但在25℃处理下其K值上升120%。虽然中肋骨条藻的r在两个温度下均受海洋卡盾藻添加的促进, 但其K值从20℃下的上升43%转变为25℃下的降低48%。温度变化对于抑食金球藻和中肋骨条藻共培养的结果无明显影响, 中肋骨条藻的K均上升40%, 而抑食金球藻的K值均下降60%~70%。结果说明, 种间竞争除了共培养藻固有的相互作用关系因素外, 也受到微藻间温度适应性差异的影响。在20℃条件下三种藻混合, 抑食金球藻K的抑制率达到最高为79%, 而中肋骨条藻K的促进率达到最高为108%, 这可能表明三者之间的相互作用存在协同效应。  相似文献   

Vertical distribution of primary producers and zooplankton grazers during different phases of the Arctic spring bloom     

Fredrika Norrbin  Hans Chr. Eilertsen  Maria Degerlund 《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(21-22):1945

During a circumnavigation of the Svalbard archipelago in May 2006, simultaneous marine environmental (meteorology, heat flux, ocean turbulence, irradiance) and biological (phytoplankton and zooplankton biomass/species) data were sampled at selected stations. The zooplankton data were supplemented by high-resolution, high-speed VPR sampling down to 100 m depth at most stations. We were able to sample different phases of the phytoplankton spring bloom in Arctic as well as in Atlantic waters, and the stations represented different situations with respect to irradiance, turbulence and water-column stability. Phytoplankton growth and depth distribution were physically controlled, while zooplankton distributions were affected by biological parameters and turbulence. Development of the zooplankton followed the phytoplankton bloom phase, which was progressing in a direction from west to east in the waters north of Svalbard, and southwards in the Barents Sea. Our results also showed that the zooplankton did not avoid Phaeocystis pouchetii colonies, which have earlier been described as toxic. Despite an early retreat of the ice this year there was no apparent mismatch between the phytoplankton bloom and the dominant mesozooplankton, Calanus spp.  相似文献   

舟山渔场及其相邻赤潮高发区麻痹性贝类毒素研究   总被引：2，自引：0，他引：2       下载免费PDF全文

胡颢琰  唐静亮  黄备  毛宏跃  王婕妤  魏娜 《海洋与湖沼》2008,39(5):475-481

采用小白鼠生物检测法和高效液相色谱荧光检测法，对采自舟山渔场及其相邻赤潮高发区贝类的麻痹性贝毒素进行了调查分析与研究。结果表明，浙江舟山海域有毒贝类检出率为7．0％。利用高效液相色谱荧光检测法对2006年5月份采集的六横的西格织纹螺、岱山的毛蚶组织提取液进行麻痹性贝毒素测定，结果显示，六横的西格织纹螺体内麻痹性贝毒素含量为0．178Mu／g，毒力值为0．0356μg STXeq／g，其毒素成分由GTX2、GTX3、STX、dcSTX、C2组成：岱山的毛蚶体内麻痹性贝毒素含量为3．494Mu／g，毒力值为0．6987μg STXeq／g，其毒素成分由STX、NEO、C1、C2组成。浙江中、南部海域有毒贝类检出率为2．2％，利用高效液相色谱荧光检测法对2006年10月份在南麂列岛采集的棒锥螺的组织提取液进行麻痹性贝毒素的测定，结果显示棒锥螺体内麻痹性贝毒素含量为0．705Mu／g，毒力值为0．1409μg STXeq／g，其毒素成分有GTX1、GTX2、GTX3、NEO、C1、C2组成。  相似文献   

Effect of enclosure and nutrient enrichment on Microcystis blooms in Donghu Lake     

唐汇娟  谢平  谢丽强  陈非洲 《中国海洋湖沼学报》2006,24(3):278-284

1 INTRODUCTION Surface blooms of nuisance cyanobacteria are often a signal of eutrophication (Jacoby et al., 2000). They are generally favored by conditions of low nitrogen to phosphorus ratios, high total phosphorus content, high water temperature, high …  相似文献   

三峡水库澎溪河春季水华期p(CO₂)及影响因素分析   总被引：5，自引：0，他引：5  

郭劲松  蒋滔  李哲  陈永柏  孙志禹 《水科学进展》2011,22(6):829-838

在三峡水库澎溪河回水区春季水华连续暴发期间(2010年4月10日至5月25日),对渠马至河口总计5个采样断面进行监测。结果表明水华期间水体叶绿素a(Chla),溶解氧(DO)及CO₂分压(p(CO₂))分层现象明显,表层水体受浮游植物光合作用的影响p(CO₂)较低,并且日照充足时,水体为CO₂的汇。研究期间表层水体p(CO₂)最小值出现在4月25日双江断面,为4.3Pa,吸收通量为-0.28 mmol/(m2·h)。p(CO₂)随水深迅速增加,并在10～15m趋于稳定。偏最小二乘回归分析(PLS)表明澎溪河水华期间,浮游植物的生长代谢是控制p(CO₂)的关键因素,水温与p(CO₂)负相关,但并不构成对p(CO₂)的绝对影响。通过引用Ep(CO₂)/ADO参数,观测到了澎溪河水体水华暴发的3个阶段,期间澎溪河表层水体经历了从碳汇到碳源最后又回到碳汇的过程。  相似文献   

太湖水体水温垂向分层特征及其影响因素   总被引：8，自引：0，他引：8  

赵林林  朱广伟  陈元芳  李未  朱梦圆  姚昕  蔡琳琳 《水科学进展》2011,22(6):844-850

为揭示大型浅水湖泊水温分层特征及其影响因素,采用温度链,高频观测太湖水温分层的周年变化过程.结果表明:太湖水体水温的垂向温差绝大多数处在0～l℃,部分处于l ～4C,偶尔超过4℃;太湖水体水温垂向温差存在季度、月、日差异,相应的分层位置也不同;水温分层影响因素包含太阳辐射、气温、风速、水密度和比热、藻华堆积等.随着太阳...  相似文献   

Population dynamics of phytoplankton, heterotrophic bacteria, and viruses during the spring bloom in the western subarctic Pacific     

Koji Suzuki  Akira KuwataNaoki Yoshie  Akira Shibata  Kyoko KawanobeHiroaki Saito 《Deep Sea Research Part I: Oceanographic Research Papers》2011,58(5):575-589

We characterized the community composition of phytoplankton in the western subarctic Pacific from the pre-bloom to the decline phase of the spring bloom with special reference to decreases in the silicic acid concentration in surface waters as an index for diatom bloom development. Furthermore, responses of heterotrophic bacteria and viruses to the spring bloom were also concomitantly investigated. Under pre-bloom conditions when nutrients were abundant but the surface mixed layer depth was relatively deep, chlorophyll (Chl) a concentrations were consistently low and green algae (chlorophytes and prasinophytes), cryptophytes, and diatoms were predominant in the phytoplankton assemblages as estimated by algal pigment signatures. Together with the shallowing of the mixed layer depth and the decrease in silicic acid concentration, diatoms bloomed remarkably in the Oyashio region, though the magnitude of the bloom in the Kuroshio-Oyashio transition (hereafter Transition) region was relatively small. A total of 77 diatom species were identified, with the bloom-forming diatoms mainly consisting of Thalassiosira, Chaetoceros, and Fragilariopsis species. It has become evident that the carotenoid fucoxanthin can serve as a strong indicator of the diatom carbon biomass during the spring diatom bloom. Differences in the species richness of diatoms among stations generally enabled us to separate the Oyashio bloom stations from the Transition and the Oyashio pre-bloom stations. Relatively high values of the Shannon-Wiener index for the diatom species were also maintained during the Oyashio bloom, indicating that a wide variety of species then shared dominance. In the decline phase of the Oyashio bloom when surface nutrient concentrations decreased, senescent diatom cells increased, as inferred from the levels of chlorophyllide a. Although the cell density of heterotrophic bacteria changed little with the development of the diatom bloom, viral abundance increased toward the end of the bloom, suggesting an increased likelihood of mortality among organisms including diatoms resulting from viral infection. This is the first report on the microbial trophodynamics, including viruses, during the spring diatom bloom in the western subarctic Pacific.  相似文献