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1.
Meso-scale spatial distribution of large tintinnids in early summer in southern Yellow Sea 总被引：2，自引：0，他引：2
The spatial distribution of some large tintinnid species （nominally〉76 μm） was investigated according to samples collected by vertical towing in cruises to the southern Yellow Sea in summer 2000-2002 and 2004. Eight species were identified： Codonellopsis mobilis, Leprotintinnus netritus, Tintinnopsis karajacensis, T. japonica, T. kiaochowensis, T. butschlii, T. radix, and Parafavella sp. With maximum abundance of 158.2 ind/L in June 2004, C. mobilis was the dominant species, lasting from May to July 2004. Tintinnid communities were patchy and distributed mainly in shallow waters along the shore. 相似文献
2.
Wintertime meso-scale horizontal distribution of large tintinnids in the southern Yellow Sea 总被引：1，自引：0，他引：1
Spatial distribution of some large tintinnid species (nominally > 76 μm) is investigated on samples vertically towed in the southern Yellow Sea in winters of 2001 to 2004. Nine tintinnid species are recorded: Codonellopsis morchella, Stenosemella pacifica, S. steini, Tintinnopsis schotti, T. radix, T. karajacensis, Eutintinnus tenuis, Parafavella sp., Leprotintinnus neriticus, of which C. morchella and T. radix dominated in the warm tongue-shaped zone of the Yellow Sea Warm Current (YSWC), and S. pacifica i... 相似文献
3.
Coastal region on the Antarctic continent, where it is under the influences both of ocean and ice sheet, as well as frequent human activities, could be considered as a fragile zone in Antarctic ecological environment. There are many lakes in coastal region, showing much differences from each other in physical-chemical features because of individual evolutionary history in their geographical environments, and suffering from different outside factors, such as climate changes and precipitation. Thus, it results in respective biological distribution and ecological structure in lakes. The present paper reports the results from the studies of chemical components, species distributions and community structures, which mainly consisted of planktons in lakes in the Vestfold Hills (68°38＇S, 78°06＇E), and the Larsemann Hills (69°30＇S, 76°20＇E), East Antarctica. It also treats the biological diversities and nutrient relationships of these different types of lakes. So as to provide more scientific basis for monitoring of climate changes and environmental protection in Antarctica. 相似文献
4.
石界河群小寨组主要为砂、泥质碎屑沉积,按岩性可分为四个组合,下部黑云母石英片岩与变质杂砂岩组合及变质副砾岩与变质杂砂岩组合为浊流及碎屑流沉积,上部的变质砾岩与变质含砾砂岩组合及变质杂砂岩、千枚岩组合为扇三角洲沉积。综合上述沉积相组合,提出小寨组并非大洋或深海盆地,而应为靠近陆源地的断陷盆地中的碎屑沉积。 相似文献
5.
Glaciogene sedimentary rocks have been found in modem tills of the Grove Mountains, east Antarctica during the 1998 - 1999 Chinese National Antarctic Research Expedition （CHNARE）. Based on the lithilogic and sedimentary features, these sedimentary rocks are correlated with Cenozoic sedimentary strata of the Pagodroma Group in the neighboring Prince Charles Mountains and the Sorsdal Formation in VestFold Hills. Sedimentary clasts contain sparsely Late Tertiary spores and pollens, including ： Toroisporis （ Lygodiaceae）, Osmunda, Granulatisporites （ Pteridaceae？） , Polypodiaceae, Podocarpus , Araucariaceae, Artemisia , Rhus , Nothofagidites , Proteacidites （Proteaceae） , Quercus , Fraxinoipollenites （ Oleaceae ） , Oleoidearumpollenites（ Oleaceae ）, Operculumpollis, and Tricolpopollenites. Most of the pollen and spores contained in these samples originate from local sources according to the conditions of their preservations as well as correlations with the microfossil assemblages found in the neighboring areas. The majority of the pollen assemblages, as represented by Podocarpus and Nothofagus, belong to the Weddellian biogeocenose, however some exotic components from the old sedimentary basement rocks may have been included during erosion of the proximal ice sheet. If the source areas of glaciogenic sedimentary rocks that bear the pollen and spores are assumed to be local, or in the up glacier areas, the pollen assemblages in these samples might represent an inland flora during a warmer period of the ice-sheet evolutionary history. The finding of the Artemisia and Chenopodiaceae in the pollen assemblages implies that they may belong to late Tertiary （most probably Pliocene）. The absence of diatoms in the samples analyzed may indicate that there are no Cenozoic marine strata in the interior of the east Antarctica beyond the Grove Mountains. The significances of the finding of the Nothofagus in these pollen assemblages are discussed on the basis of current knowledge about the age, distribution and ecological conditions of this kind of fossils found in Sirius Group or other strata outcropped in Antarctica. As a preliminary conclusion, we think that the existence of the Cenozoic glaciogenenic rocks and their pollen assemblages present new evidence for a large scale glacial retreat history in Grove Mountains of east Antarctica, and thus support a dynamic East Antarctic Ice Sheet （EAIS）. This is consistent with the interpretations of Webb et al. （1984）. 相似文献
6.
宁波盆地地下揭示的一套包含暗色膏硝质泥岩、泥质白云岩在内的紫红、灰紫色泥岩、棕褐色砂砾岩、细砂岩和玻屑凝灰岩的地层，均称方岩组，内含膏盐并具油色显示。对其时代有早、晚白垩世和早第三纪之认识，笔者从70～90年代地质工作中所获化石分析认为，虽然宁波盆地这一层位含化石不丰，但从分布及数量上比较，相对占优势的应该是孢粉和植物化石，其时代意见也较为一致，指示为早白垩世。 相似文献
7.
Population dynamics of four dominant Antarctic copepods, Calanoides acutus, Calanus propinquus, Metridia gerlachei and Rhincalanus gigas were studied based on zooplankton samples collected in the Prydz Bay during austral summer from 1999 to 2006. We found that C. acutus was the most abundant species among these four copepods, followed by C. propinquus, M. gerlachei and R. gigas. R. gigas occurred mainly in the warmer oceanic regions and showed distribution patterns discrete from the other three species, whose distribution in the whole survey area overlapped. By December 15th (about one month before our sampling) of the years 1999, 2003 and 2006, sea ice retreated earlier and polynyas existed in the neritic region one month before sampling. These periods were characterized by numerical dominance of C. acutus, C. propinquus and M. gerlachei, elevated proportions of Copepodite I and Copepodite II stages especially in the neritic region. While for the years 2000, 2002, and 2005, the ice edge located more northerly and polynyas did not exist in the neritic region, the copepods abundance was lower, indicating poor recruitment. Population structure of R. gigas was mainly composed of advanced stages Copepodite V and female during all cruises. Log10 (x+1) transformed densities of C. acutus, C. propinquus and M. gerlachei showed positive correlation with temperature and chlorophyll a concentration, while mean population stages of these copopods were negatively correlated with these environmental variables. Younger copepodite stages of C. acutus, C. propinquus and M. gerlachei appeared more often in neritic regions. We confirmed that the polynyas had a great contribution to phytoplankton blooms, which promote copepods reproduction and recruitment success. The study suggested that population dynamics of the four copepods have good correspondence with sea ice and polynya variations during all cruises of the Prydz Bay. 相似文献
8.
9.
辽河群主要由石英片岩,板岩-千枚岩、浅粒岩-变粒岩、斜长片麻岩组成。其中石英片岩、板岩-千枚岩和斜长片麻岩具有Si、Al,K相对偏高的特点,为Au、Pb、Zn、Ag、F等元素的主要荷载岩石。浅粒岩-变粒岩富集B、As、S、Zr、La、Pb、Ag、Ba等元素,为B的矿源体。这几种岩石稀土元素组成具有变质沉积岩的稀土分配特征。片岩、浅粒岩和变粒岩的原岩,主体为沉积岩,个别为火山岩,前者主要来源于大陆上部地壳;后者属上地幔或接近于大陆溢流玄武岩的物质经部分熔融的产物。其微量元素均可分为二大群,组合形式多不相同。 相似文献
10.
Ecological end palaeoecological studies were carried out in a series of lakes in the Vestfold Hills (68°38＇S, 78°06＇E) on eastern Antarctic continent. Dynamics types of the lakes in environmental geomorphology and physic-chemistry, as well as features of biological community structures in different lakes were analyzed. Marine macro- and micro-fossils collected from the terraces and beaches surrounding these lakes and determined in 14C radiocarbon ages to be the Late Pleistocene, were used as evidences tc show the evolutionary processes of the lakes after sea level changes and transgressions since 18000 a B.P.. Basic modals of evolution for the lakes given in the paper could be regarded as not only explaining the history of environmental and ecological changes in VH lakes, and also reflecting of local environmental evolution in Antarctic region and global climate changes from past to present time. 相似文献
11.
2002、2005和2006年7~8月,对广东省湛江市高桥红树林区的鱼类进行了调查,共采集到鱼类75种,隶属于13目38科,其中鲈形目有40种,占53.3%,是高桥红树林区鱼类主要种类。测定了主要鱼类的体重、数量、大小、分析了其食性。 相似文献
12.
The species composition and abundance of microzooplankton at 10 marine and five coastal stations(Hongdao,Daguhe,Haibohe,Huangdao and Hangxiao) in the Jiaozhou Bay(Qingdao,China) were studied in 2001.The microzooplankton community was found to be dominated by Tintinnopsis beroidea,Tintinnopsis urnula,Tintinnopsis brevicollis and Codonellopsis sp.The average abundance of microzooplankton was highly variable among stations.Specifically,the abundance of microzooplankton was higher at inshore stations and lower ... 相似文献
13.
湛江高桥红树林区鱼类调查 总被引：1，自引：0，他引：1
2002、2005和2006年7～8月，对广东省湛江市高桥红树林区的鱼类进行了调查，共采集到鱼类75种，隶属于13目38科，其中鲈形目有40种，占53．3％，是高桥红树林区鱼类主要种类。测定了主要鱼类的体重、数量、大小，分析了其食性。 相似文献
14.
Parametamorphic rocks from Arong County in southeastern Inner Mongolia-Daxinganling district are regarded as Proterozoic in age,belonging to the Wolegen Group and composed of volcanoclastic and sandstone in origin,and have been disputed in tectonic setting.Because of the stability in metamorphism,the rare earth dements indicate the features of their protoliths.The authors integrated the petrologic methods with the geochemical parameters which include ∑REE,∑LREE/∑HREE,δCe,δEu,La/Yb,Sm/Nd,Th/Sc and the standard values of chondrite.The results show that the protoliths of Wolengen Group may be a group of voleanoclastic and continental margin elastic rocks,and their tectonic setting is the continent island arc. 相似文献
15.
郭安林 《地球科学与环境学报》1988,(2)
河南临汝安沟地区前嵩山群变质矿物、变质矿物组合以及变质温压条件研究表明,前嵩山群分属不同的变质建造,其中安沟群属中压相系绿片岩相变质作用,登封群头道河组为中压相系角闪岩相。同时,两套地层变质作用之间缺少钠长—绿帘角闪岩相,这一变质作用的间断,从一个侧面反映了地层的间断。 相似文献
16.
Seagrass research in China is still in its infancy. Even though there has been progress recently, there is still a great deal
of research needed to gain a better understanding of seagrass. In this article we review and discuss the advances in seagrass
research in China from two aspects: (1) seagrass species and their distribution; (2) seagrass research in China, including
studies on their taxonomy, ecology, photosynthesis, applications in aquaculture, salt-tolerance mechanisms and other research
topics. A total of 18 seagrass species belonging to 8 genera are distributed in nine provinces and regions in China (including
Hong Kong and Taiwan), as well as the Xisha and Nansha Archipelagos. They can be divided into two groups: a North China Group
and a South China Group. Based on the seagrass distribution, the Chinese mainland coast can be divided into three sections:
North China Seagrass Coast, Middle China Seagrass Coast, and South China Seagrass Coast. Ecological studies include research
on seagrass communities, nutrient cycling in seagrass ecosystems, genetic diversity, pollution ecology and research in the
key regions of Shandong, Guangdong, Guangxi, and Hainan. Seagrass species and their locations, community structure, ecological
evaluation, epiphytes, ecological functions and threats in the key regions are also summarized. Other studies have focused
on remote sensing of seagrass, threatened seagrass species of China, and pollen morphology of Halophila ovalis. 相似文献
17.
Xue Chen Haibo Li Yuan Zhao Li Zhao Yi Dong Wuchang Zhang Tian Xiao 《中国海洋大学学报(英文版)》2018,17(2):371-384
There were different biogeographical tintinnids in the oceans. Knowledge of their distribution pattern and mixing was important to the understanding of ecosystem functions. Yellow Sea (YS) and Bohai Sea (BS) were semi-enclosed seas influenced by warm water intrusion and YS cold bottom water. The occurrence of tintinnids in YS and BS during two cruises (summer and winter) were investigated to find out: i) whether warm-water tintinnids appeared in YS and BS; ii) whether boreal tintinnids appeared in high summer; iii) the core area of neritic tintinnids and iv) how these different biogeographical tintinnids mixed. Our results showed that tintinnid community was dominated by neritic tintinnid. We confirmed the occurrence of warm-water tintinnids in summer and winter. In summer, they intruded into BS and mainly distributed in the upper 20 m where Yellow Sea Surface Warm Water (YSSWW) developed. In winter, they were limited in the surface water of central deep region (bottom depth >50 m) of YS where were affected by Yellow Sea Warm Water (YSWW). Boreal tintinnids occurred in YS in high summer (August) and in winter, while they were not observed in BS. In summer, the highest abundance of boreal tintinnids occurred in Yellow Sea Bottom Cold Water, indicating the presence of an oversummering stock. In winter, they were concentrated in the north of YSWW. Vertically, neritic tintinnids abundance was high in the bottom layers. Horizontally, high neritic tintinnids abundance in bottom layers occurred along the 50 m isobath coinciding with the position of front systems. Front systems were the core distribution area of neritic tintinnids. High abundance areas of warm-water and boreal tintinnids were clearly separated vertically in summer, and horizontally in winter. High abundance of neritic tintinnids rarely overlapped with that of warm-water or boreal tintinnids. 相似文献
18.
Decreasing fish resources in estuaries is a subject of anthropogenic activities.Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery.As the fifth largest river estuary in the world,the Huanghe(Yellow)River estuary(HRE)is a typical estuary that has been seriously affected by human activities.Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated influencing factors.A total of 23 and 20 species of eggs and larvae,respectively,were collected.The dominant orders were Perciformes(51.2%)and Clupeiformes(25.6%).The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m~3,respectively.The dominant species were mainly low-commercial-value small-sized fishes,such as Clupanodon punctatus,Hare,ngula zutnasi,and Acanthogobius,whereas certain traditional commercial fishes,such as Trichiurus lepturus,and Clupea pallasii,were not seen.Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages.Salinity was the main factor on the spatial distribution of ichthyoplankton communities,the species number and Shannon-Weiner diversity index(H')of the fish egg and larval community near the river mouth with lower salinity were significantly lower than the community far away from the river mouth with higher salinity.In addition,increases of water temperature promoted the number and abundance of fish species eggs,and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species.In overall,overfishing,dam construction,and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE. 相似文献
19.
Variations in physical-chemical factors, species composition, abundance and biomass of nano- and micro-phytoplankton assemblages,
as well as their responses to environmental factors, were investigated over a complete cycle (6 months) in a semi-enclosed
shrimp-farming pond near Qingdao, northern China. The aim was to establish the temporal patterns of phytoplankton communities
and to evaluate protists as suitable bioindicators to water quality in mariculture systems. A total of 34 taxa with nine dominant
species were identified, belonging to six taxonomic groups (dinoflagellates, diatoms, cryptophyceans, chlorophyceans, euglenophyceans
and chrysophyceans). A single peak of protist abundance occurred in October, mainly due to chlorophyceans, diatoms and chrysophyceans.
Two biomass peaks in July and October were primarily due to dinoflagellates and diatoms. Temporal patterns of the phytoplankton
communities significantly correlated with the changes in nutrients, temperature and pH, especially phosphate, either alone
or in combination with NO3-N and NH3-N. Species diversity, evenness and richness indices were clearly correlated with water temperature and/or salinity, whereas
the biomass/abundance ratio showed a significant correlation with NO3-N. The results suggest that phytoplankton are potentially useful bioindicators to water quality in semi-enclosed mariculture
systems. 相似文献
20.
Cheng Shaohua Zhang Xia Zhu Jiangang Zhao Weiquan Ling Xiaoliang Li Shenggui Fang Binxian Zhao Huili 《极地研究(英文版)》2000,11(1)
Based on the general framework of ADDS (Antarctic Data Directory System) established by SCAR-COMNAP ad hoc Planning Group on Antarctic data management, the CN—ADDS (Chinese Antarctic Data Directory System ) project is going on, of which the research and activity keeps to the available method and technique in ADDS development and allows for the Chinese specific status in Antarctic data management as well. At present, authoring and submitting timely Antarctic data directory in China is one of the key issues that is to be dealt with necessarily. This paper aims at studying the technical procedure in collecting, processing, examining and submitting data directory. In additional, it also discusses the efficient collection of data directory, which needs the effort of administrative and technical support 相似文献