Holocene environmental change according to lake core in Fildes Peninsula of King George Island,Antarctica     

李小梅  袁宝印  赵俊琳 《极地研究(英文版)》2002,13(2)

Lake core sampled from Xihu in Fildes Peninsula of King Gorge Island, Antarctica could reveal the environmental change of the district. The lake core( GA7) , 9.28 meters long , was sectioned at an interval of 2 cm. Through measuring the organic carbon, magnetic susceptibility, granularity and organic carbon isotope of GA7, by use of 14C age it was estimated that there were four periods of high temperature in Fildes Peninsula; 4800-4400 aB. P. , 3600-3350 aB. P. ,2100 - 1800 aB. P. and 900 aB. P. - present. Meanwhile, results showed that there was a strikingly positive correlation between the content of organic carbon and that of organic carbon isotope (δC01213 ) which could be the substitute indicators of environmental temperature.  相似文献   

Glacial Lake Victoria,a high‐level Antarctic Lake inferred from lacustrine deposits in Victoria Valley     

Brenda L. Hall  George H. Denton  Bret Overturf  Chris H. Hendy 《第四纪科学杂志》2002,17(7):697-706

We present evidence of a large lake (Glacial Lake Victoria) that existed in Victoria Valley in the dry valleys region of Antarctica between at least 20 000 and 8600 ¹⁴C yr BP. At its highstands, Glacial Lake Victoria covered 100 km² and was ca. 200 m deep. The chronology for lake‐level changes comes from 87 AMS radiocarbon dates of lacustrine algae preserved in deltas and glaciolacustrine deposits that extend up to 185 m above present‐day lakes on the valley floor. The existence of Glacial Lake Victoria, as well as other large lakes in the dry valleys, indicates a climate regime significantly different from that of today at the last glacial maximum and in the early Holocene. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

A preliminary application GIS in glaciological research along the traverse route from Zhongshan Station to Dome A, Antarctica   总被引：1，自引：0，他引：1  

温家洪  孙波  康建成  李院生 《极地研究(英文版)》2003,14(1)

1　IntroductionGeographicalinformationsystem (GIS)isanefficientwayandimportanttechniquetomanage,displayandanalyzeAntarcticspatialdata.GIScanbeusedtomakeandre newmapproductsquickly ,evaluateenvironment,supportlogisticmanagementandfieldoperation,providechancetoextractnewknowledge,andtopromoteinformationex changeamongnationsunderthedemandoftheMadridProtocol(AADC 2 0 0 1 ;MAGIC1 998;1 999) .WorkingGroupofGeodesyandGeographicInformation (WG GGI)ofScientificCommitteeonAntarcticResearch (…  相似文献   

Preliminary study on the spore-pollen assemblages found in the Cenozoic sedimentary rocks in Grove Mountains, east Antarctica and its climatic implications     

方爱民刘小汉  王伟铭李潇丽俞良军  黄费新 《极地研究(英文版)》2005,16(1):23-32

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   

南极长城站酸雨监测的样品采集与分析   总被引：4，自引：0，他引：4       下载免费PDF全文

王国贵 《极地研究》1999,11(1):64-71

进行南极酸性湿沉降（降水ｐＨ值＜５．６）的监测研究是为开展全球环境大气化学动态监测、评价区域环境质量、制定环境标准,研究环境中化学元素的迁移、转化、富集规律,以及南极资源的保护和合理开发利用提供第一手的科学依据。利用１９９８年１～９月在中国南极长城站采集监测的酸雨资料综合分析得出,南极确有酸雨存在,在１０４个水样中,有１９个样品的ｐＨ值小于５．６,占总样品的１８．３％。根据南极环境背景值和出现酸雨时的风向,认为由于大气环流把远离南极的污染源传输到南极上空,遇降水即冲刷降至地面形成酸雨  相似文献   

南极海豹类生态学   总被引：1，自引：0，他引：1       下载免费PDF全文

董金海  王广洁  冯洁 《极地研究》1999,11(2):59-65

描述了南极海豹的种类组成、资源量和种类状况等一般性生态学问题,着重讲述了这些海豹在研究全球变化中所起的作用等科学前沿问题;同时,就海豹研究在各国际组织中的地位阐述了意见。  相似文献   

西南极利文斯顿岛含砾泥岩层的发现及其地质意义   总被引：1，自引：0，他引：1       下载免费PDF全文

邓希光  郑祥身  刘小汉 《极地研究》1999,11(3):169-178

西南极南设得兰群岛利文斯顿岛赫德半岛中分布的一套主要由复理石相岩石组成的低级变质沉积岩（迈尔斯陡崖组）被认为是中－ 新生代火山岩的基底（晚古生代－ 早中生代？）。以前含砾泥岩在迈尔斯陡崖组局部地点曾有零星报道,但详细的地质填图确认此地有四层含砾泥岩分布。研究表明,这些含砾泥岩可能是水下碎屑流沉积,其生成环境可能是海底扇中扇的水道。对比在南极半岛所发现有大量的含砾泥岩,则进一步表明利文斯顿岛早期地质特征可与南极半岛相比,两者在中－ 新生代岩浆弧形成之前处于相同的构造环境。  相似文献   

南极长城站和中山站辐射特征的研究   总被引：9，自引：1，他引：8       下载免费PDF全文

卞林根  陆龙骅 《应用气象学报》1998,9(2):160-168

对南极长城站和中山站1993～1994年辐射资料的分析表明:两站辐射分量的季节变化特征基本相似。但由于气候状况的差异,长城站到达地面的总辐射和吸收辐射分别为中山站的51%和42%。极昼期间（11～1月）中山站总辐射和紫外辐射总量均超过了青藏高原夏季（6～8月）的总量,两站净辐射夏半年为正,冬半年为负,显示出南极绿洲的辐射气候特点。  相似文献   

First evidence of Pentoxylales in Antarctica     

S.N. Césari  C.A. Parica  M.B. Remesal  F.M. Salani 《Cretaceous Research》1998,19(6):733-743

Plant remains from the Byers Peninsula, South Shetlands Islands, are described. These are leaves referred toTaeniopterissp. and female fructifications referred toCarnoconites llambiasiiCésari sp. nov. They are considered to belong to the Pentoxylales, originally described from India, Australia and New Zealand. This is the first record of this group of gymnosperms from Antarctica. The occurrence contributes to further differentiation between floras of this part of Gondwana and Laurasia.  相似文献   

Ice-core records of global climate and environment changes     

Robert J. Delmas 《Journal of Earth System Science》1998,107(4):307-319

Precipitation accumulating on the Greenland and Antarctic ice sheets records several key parameters (temperature, accumulation, composition of atmospheric gases and aerosols) of primary interest for documenting the past global environment over recent climatic cycles and the chemistry of the preindustrial atmosphere. Several deep ice cores from Antarctica and Greenland have been studied over the last fifteen years. In both hemispheres, temperature records (based on stable isotope measurements in water) show the succession of glacial and interglacial periods. However, detailed features of the climatic stages are not identical in Antarctica and in Greenland. A tight link between global climate and greenhouse gas concentrations was discovered, CO₂ and CH₄ concentrations being lower in glacial conditions by about 80 and 0.3 ppmv, respectively, with respect to their pre-industrial levels of 280 and 0.65 ppmv. Coldest stages are also characterized by higher sea-salt and crustal aerosol concentrations. In Greenland, contrary to Antarctica, ice-age ice is alkaline. Gas-derived aerosol (in particular, sulfate) concentrations are generally higher for glacial periods, but not similar in both the hemispheres. Marine and continental biomass-related species are significant in Antarctica and Greenland ice, respectively. Finally, the growing impact of anthropogenic activities on the atmospheric composition is well recorded in both polar regions for long-lived compounds (in particular greenhouse gases), but mostly in Greenland for short-lived pollutants.  相似文献