Dinoflagellate cyst stratigraphy and palaeoenvironment of the marginal marine Middle and Upper Miocene of the eastern Campine area,northern Belgium (southern North Sea Basin)     

Stephen Louwye  Pieter Laga 《Geological Journal》2008,43(1):75-94

A stratigraphical and palaeoenvironmental analysis with organic‐walled palynomorphs of the Bolderberg and Diest formations provides new insights in the depositional history during Miocene times at the southern border of the North Sea Basin. The Neogene transgression invaded Belgium from a north–northwestern direction and fully marine sediments were deposited in the northern part of Belgium. The age and the palaeoenvironment of the deposits at the very border of the southern North Sea Basin remained till a few decades ago incomplete. The recovered dinoflagellate cysts, acritarchs and green algae from the Bolderberg Formation in the Wijshagen Borehole indicate a marginal marine depositional environment during late Burdigalian and Langhian times in the eastern Campine area, in contrast to the deeper marine conditions prevailing to the north–northwest. The relative dating of the Bolderberg Formation confirms that maximum flooding occurred during Langhian to early Serravallian times. Deposition apparently took place during the Middle Miocene Climatic Optimum, and ended when the climatic deterioration set in at around 14 Ma. A hiatus spanning ca. 2 Ma separates the Middle Miocene Bolderberg Formation from the Upper Miocene Diest Formation in the eastern Campine area at the border of the North Sea Basin. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

Correlation of Barremian-Aptian (mid-Cretaceous) dinoflagellate cyst assemblages between the Tethyan and Austral realms     

A.M. Oosting  H. Leereveld  G.R. Dickens  R.A. Henderson  H. Brinkhuis 《Cretaceous Research》2006,27(6):792-813

Quantified organic-walled dinoflagellate cyst (dinocyst) assemblages are presented for two sedimentary successions deposited in neritic environments of the Tethys Ocean during the Barremian and Aptian in an attempt to reconcile established dinocyst biostratigraphic schemes for Tethyan and Austral regions. One section is at Angles, southeast France (the Barremian stratotype section); the other is at Deep Sea Drilling Project Site 263, off northwest Australia. We also construct a carbon isotope record for Site 263 using bulk organic carbon.Both sections contain abundant, well-preserved dinocyst assemblages. These are diverse, with 89 taxa identified at Angles and 103 taxa identified at Site 263. Of these, more than 93% are cosmopolitan. When combined with other work at Angles and Site 263, we found that nine dinocysts have their first occurrence (FO) or last occurrence (LO) at both locations. These dinocyst events are, in alphabetical order: LO of Cassiculosphaeridia magna, FO of Criboperidinium? tenuiceras, LO of Kleithriasphaeridium fasciatum, LO of Muderongia staurota, FO of Odontochitina operculata, LO of Phoberocysta neocomica, FO of Prolixosphaeridium parvispinum, FO of Pseudoceratium retusum var. securigerum, and FO of Tehamadinium sousense. Although these events support a Barremian–Aptian age for both sections, their stratigraphic order is not the same in the sections. The δ¹³C_org record at Site 263 displays a characteristic series of changes that have also been recorded in other carbon isotope curves spanning the Late Barremian–Early Aptian. Such independent dating (along with ammonite zones at Angles) suggests that three of the nine dinocyst events are approximately isochronous at Angles and Site 263: the LO of K. fasciatum in the mid Barremian, the FO of P. retusum var. securigerum and the FO of C.? tenuiceras in the earliest Aptian; the other six dinocyst events are diachronous. Dinocyst assemblages at Site 263 can be loosely placed within existing Australian zonation schemes, providing much-needed calibration. Our data suggest that the Muderongia testudinaria Zone ends in sediments of mid Barremian age, the succeeding Muderongia australis Zone extends into the Early Aptian, and the younger Odontochitina operculata Zone begins in Early Aptian deposits. The boundary between the M. australis and O. operculata zones, and the Ovoidinium cinctum (as Ascodinium) Subzone, positioned at the top of the M. australis Zone when present, could not be recognized incontrovertibly. Interestingly, however, this horizon broadly correlates with the onset and extent of the Selli Event, a time of major biogeochemical change.  相似文献   

中国沿海寄生性病原血卵涡鞭虫(Hematodinium sp.)的遗传多样性研究     

肖洁  张学雷  刘瑞娟  李才文 《海洋与湖沼》2015,46(3):481-488

血卵涡鞭虫是一类感染海洋甲壳类动物的寄生性甲藻。本研究通过对我国山东、浙江和广东三地的血卵涡鞭虫群体进行r DNA基因(包括5.8S,ITS1和ITS2)的测序和遗传分析,研究了我国沿海养殖蟹类中血卵涡鞭虫群体的遗传多样性以及与美国和欧洲群体的亲缘关系。结果表明,流行于我国沿海地区养殖蟹类中的血卵涡鞭虫群体存在一定的遗传多态性,共发现14个单倍型,其中单倍型ST041a在各个群体中均有出现,且发生频率较高;而三个地理群体之间无明显遗传差异,侵染不同宿主(三疣梭子蟹和拟穴青蟹)的株系间也无显著遗传差异。另外,我国的上述群体在遗传上是不同于国际上其他地区的独立分支,属于Hematodinium perezi基因型Ⅱ;其亲缘关系与美国兰蟹中的株系较近(遗传距离D=0.027),而与欧洲冷水株系稍远(D=0.236)。本研究肯定了血卵涡鞕虫是一类"泛宿主"型病原生物,即在同一地区可侵染不同的甲壳类宿主。我国沿海地区的蟹类养殖应避免不同种类间的混养,以及不同地区间的引种交换,以防止血卵涡鞕虫流行病的进一步扩散。  相似文献   

1998年春季珠江口海域大规模赤潮原因生物的形态分类和生物学特征Ⅲ   总被引：12，自引：8，他引：12  

黄长江  董巧香 《海洋与湖沼》2001,32(1):1-6

对1998年4月22—24日采集于广东珠江口大规模赤潮海域之一的深圳湾的活体水样和福尔马林固定水样进行赤潮原因生物的形态分类和群落构成研究。结果发现，深圳湾赤潮水样里仍以甲藻为主，但硅藻也具相当的数量。其中，最占优种为无纹螺沟藻(Gyrodiniuminstriatum),其最高密度为3.6×10  相似文献   

Preliminary study on taxonomy of dinoflagellate cysts from major estuary and bays of Fujian Province, China     

Dongzhao Lan  Chao Li  Qi Fang  Haifeng Gu 《海洋学报(英文版)》2003,22(3):395-406

According to the morphology, wall structure, color, ornamentation, etc. , 25 speciesbelonging to 9 genera are identified and described from 144 sediment samples of the Xiamen Harbor, the mouth of the Minjiang River and the Sansha Bay. Among them there are 2 toxic species: Alexandrium minutun, A. tamarenes, 4 harmful species: Alexandrium affine, Lingulodinium polyedrum , Scrippsiella trochoide, Gonyaulax spinifera. It shows that 11 species of dinoflagellate cysts (Alexandrium affine, A. minutum , Diplopelta cf. parva , Polykrikos cf. schwartzii, protoceratium reticulatum ,Protoperidinium minutum ,P. cf. minutum,P. cf americanum and Alexandrium sp. , Protoperidinium sp. 1, P . sp. 2) are first recorded along the coast of Fujian Province, China. These newly discovered species might be transported to the coastal sea of Fujian Province by ballast water of international trade vessels.  相似文献   

有毒亚历山大藻(Alexandrium spp.)和链状裸甲藻(Gymnodinium catenatum)孢囊在中国沿海的分布   总被引：4，自引：1，他引：4       下载免费PDF全文

王朝晖  MATSUOKA Kazumi  齐雨藻  吕颂辉 《海洋与湖沼》2003,34(4):422-430

于 2 0 0 0— 2 0 0 1年采集了中国沿海 1 0个采样点的表层沉积物样品 ,研究了有毒亚历山大藻 (Alexandriumspp .)和链状裸甲藻 (Gymnodiniumcatenatum)孢囊的分布。结果表明 ,这两类孢囊几乎在所有采样点都检测到。链状裸甲藻孢囊虽分布广泛 ,但含量较低 ,在样品中的浓度和百分比含量分别为 0— 71 .1cysts/gDW和 0 %— 1 4.3%。亚历山大藻孢囊在大部分海域含量较低 ,而在PSP毒素中毒事件高发区和贝类PSP毒素高含量区的大亚湾大鹏澳海域却高密度、高频率地出现 ,最高密度为 366cysts/gDW。研究结果显示 ,大亚湾大鹏澳海域表层沉积物中高密度的亚历山大藻孢囊也许是该海域贝类体内冬季PSP毒素积累及高含量的重要原因之一。  相似文献   

罗源湾口柱状沉积物中的甲藻孢囊   总被引：3，自引：0，他引：3  

孙爱梅  李超  蓝东兆  官宝聪 《台湾海峡》2006,25(1):10-18

通过时福建罗源湾口海域KMZK5柱状沉积物中甲藻孢囊的分析，共鉴定出15属30种甲藻孢囊，对比发现这30种甲藻孢囊是该湾以前未被记录的种类．其中12种是附近海域也未曾发现的种类，6种为有毒种类：缘亚历山大藻、小型亚历山大藻、塔玛亚历山大藻、具剌膝沟藻、链状裸甲藻、锥状斯氏藻，同时对甲藻孢囊的主要属种和有毒种类的丰度、分布在垂直方向上的变化特征进行了初步研究。  相似文献   

基于支持向量机分类的嘉陵江草街水库甲藻水华预警     

刘朔孺  杨敏  张方辉  张晟 《湖泊科学》2015,27(1):38-43

嘉陵江草街水库自建成后2011-2013年连续3年发生甲藻水华现象,给当地经济发展和生态安全带来影响.根据2011年5月至2013年7月草街水库大坝上、下游8个断面的逐月调查数据,利用支持向量机在处理小样本问题、非线性分类问题和泛化推广方面的优势,构建了基于支持向量机分类的草街水库甲藻水华预警模型.结果表明,利用本月理化数据和本月倪氏拟多甲藻(Peridiniopsis niei)密度数据建立的模型,对测试样本取得了80%以上的判别正确率,且对甲藻水华样本的判别正确率为100%.因此,支持向量机作为新兴的机器学习方法,可以为环境管理部门发布水华预警信息提供科学依据,并在环境保护领域具有广阔的应用前景.  相似文献   

新疆艾比湖卤虫休眠卵发育的温度因子分析   总被引：4，自引：0，他引：4  

柳光宇  黄诚  何舒宁  曾令珂  吴岷 《湖泊科学》2001,13(4):351-355

在不同的温度下对新疆艾比湖卤虫休眠卵进行了孵化试验 ,研究了卤虫发育速度与温度之间的关系 ,提出了相应的数学模型 ;V(T) =(k·T +c)·(1-exp(- (T -TH) /rH) ) ;并以此求算了该种群休眠卵孵化的最低临界温度为 5 .5 6℃ ,平均临界温度为 5 .96℃ ,最低有效积温为 342 .4 7℃×h ,平均有效积温为 4 13.6 3℃×h ;同时还就最适温度、耐温上限比较了高能卵与均能卵在适温能力上的差异 ,并最后讨论了这些参数在集约化养殖中的实践意义 .  相似文献   

Acute Toxicity of Formalin to the Red-tide Dinoflagellate Prorocentrum minimum Schiller (Protozoa, Mastigophora)     

XU Henglong)  )  SONG Weibo)  ZHU Mingzhuang)  QIU Yantao)  and MA Honggang ) The Lab of Protozoology  KLMEM  Ocean University of China  Qingdao  P.R.China ) Department of Biology  Liaocheng University  Liaocheng  P.R.China 《中国海洋大学学报(英文版)》2005,4(1)

1Introduction Red tides occur in recorded history,but in recentyears there is a global increase in the number of theseevents due to coastal pollution and other unclear fac-tors.Some kinds of red tides cause mass deaths of cul-tured animals and thus cause heavy economic losses forcoastwise mariculture(Nakanishi et al.,1996;Changet al.,1998;Zhu et al.,1998;Tada et al.,2001).The investigation on red tide control,however,rem-ains insufficient(Burkholder,1998;Edwards and Clark,1999).Although man…  相似文献