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1.
Guy Berthault 《大地测量与地球动力学》2003,23(Z1)
1 Situation1 .1 ThebasicassumptionNicolasStenonwasthefounderofstratigraphy .Itwasin 1 667,inhisworkCanisCalchariaethatheintroducedthepostulatethat:layersofsub soilare‘strata’(Fig .1 )ofancientsuccessive‘sediments’.Tobemoreprecise ,astratumisalayerofhomoge neousorsegregatedlithologicalcontent (e .g .sand stone ,limestone ,clay)betweentwosurfacelimitsofsuperposedadjacentstrata.Thesesurfacessometimescorrespondtoanerosion ,aninterruptionofsedi men tation ,characterisedbyabeddingplane,orali… 相似文献
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1 IntroductionSnowdensificationiscriticalforcalculationsinengineering glaciology,snowavalancheforecasting ,springflooding,andotherpracticalaspects.Itisalsoimportantforinterpretingicecoredataincludingthosetakenfromratherwarmsiteswheresurfacelay ersexperiencemelting ,sinceitwouldaffectthechangeofannuallayerthicknesswithtime.Whileextensivestudies(e.g .AndersonandBenson 1 963 ;Bader1 960 ,1 962 ;Koji ma 1 95 4,1 95 5 ,1 95 6,1 95 7,1 95 8,1 95 9,1 964;Keeler 1 967;Gow 1 975 ;MaenoandE binuma 1… 相似文献
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1 IntroductionCloudybandsaretypicalstratigraphicstructureindeepicecoresandtheylookwhitecolorwhenaflorescentlightwasirradiated.InWisconsinice ageiceattheGreenland ,manycloudybandsarelocatedincoldperiodsiceandcloudybandsareusedfordatingofdeepicecoresincepairofseriescloudybandandclearlayercorrespondstoannuallayer(Alleyetal.1 997;Meeseetal.1 997) .AndcloudybandcorrespondstovolcaniclayerfortheAntarcticicecore (GowandWilliamson 1 976) .Therefore,identificationofcloudybandsisimportantworkfordatin… 相似文献
4.
Yoshinori Iizuka 《极地研究(英文版)》2003,14(1)
1 IntroductionBasaliceofglaciersandicesheetshasbeenwidelystudiedtounderstandtheinacces sibleice bedinterface (e.g.,Lawson 1 979;Gowetal.1 979;Knight 1 994;HubbardandSharp 1 995 ,Souchez1 988) .Useofstableisotopesofbasaliceisasuperiormethodtodeterminewhetherthebasalicewasformedbymelt refreezingornon meltingattheinlandbaseofglaciersandicesheets.Inatheoreticalstudyofstableisotopes,JouzelandSouchez ( 1 982 )showedthatforaclosedsystem ,wherenowaterisinputoroutput,theslopegradientdefinedbyδ18O… 相似文献
5.
Phytoplankton Community Dynamics in West Lake After Drawing Water from the Qiantang River 总被引：2，自引：0，他引：2
1INTRODUCTIONTheWestLake ( 30°1 5′N ,1 2 0°1 6′E)isasmallshallowlakeinthewesternpartofHangzhouCityinthesoutheasterncoastalareaofChina.Thelakeissur roundedonthreesidesbyhills ;andisfamousforitspicturesquesceneryandinterfusionofhillsandwaterbodies.Thesurfaceareaisabout 5 .66km2 andmeandepthis 1 .8m .Beforethe 1 95 0s ,thelakewaterwascleanandmacrophytesgrewveryluxuriantlyinthelit toralareasofthelake .In 1 95 2 ,WestLakewasdredgedand 70 0× 1 0 4m3 mudwasremovedfromthebottomofthelake … 相似文献
6.
Determination of the Current System on Isopycnal Surface Between Mindanao and New Guinea from GDEM 总被引：1，自引：0，他引：1
Peter C Chu 《中国海洋湖沼学报》2003,21(3):193-213
1 .INTRODUCTIONThewesternequatorialPacific ,particularlythesouthernmostPhilippineSea ,wascalled“watermasscrossroads”byFineetal.(1 994 )duetotheconfluencethereofseveralwatermassesfromhigherlatitudesofbothhemispheres (Wyrtki,1 96 1 ;Fineetal.,1 994 ) .Fineetal.(1 994 )de picted (Fig .1 )majorcurrentsintheIndonesianregion .AfterencounteringthewesternboundaryalongthePhilippinecoast,theNorthEquatorialCur rent (NEC)bifurcatesintothenorthwardflowingKuroshioandthesouthwardflowingMindanao… 相似文献
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1 IntroductionAnicecoreobtainedfrom polarglaciersoricesheetsisoneofthemostimportantarchivestoreconstructpaleoclimaticandpaleoatmosphericcondition .Informationonpale o environmentcanbeextractedfromicecoresaschemicaland/orphysicalsignals.Amongthechemicalsignals,heavymetalsarenotedassignalsofterrestrialenvironmentalchangeandanthropogenicpollution (e.g .Murozumietal.1 969;NgandPatterson 1 981 ;Hongetal.1 994) .SinceconcentrationsofmostofthemetalsinpolarsnowincentralGreen landareatorbelowthepptl… 相似文献
8.
陈惠莲 《中国海洋湖沼学报》2001,(4)
ＩＮＴＲＯＤＵＣＴＩＯＮＲａｎｉｎｏｉｄｅｓｆｏｕｎｄｂｙＨ .ＭｉｌｎｅＥｄｗａｒｄｓ,1 83 7,ｎｏｗｉｎｃｌｕｄｅｓｓｉｘｓｐｅｃｉｅｓｉｎＩｎｄｏ ＰａｃｉｆｉｃＯｃｅａｎｓ:Ｒ .ｐｅｒｓｏｎａｔｕｓＨｅｎｄｅｒｓｏｎ ,1 888,Ｒ .ｓｅｒａｔｉｆｒｏｎｓＨｅｎｄｅｒｓｏｎ,1 888,Ｒ .ｈｅｎｄｅｒｓｏｎｉＣｈｏｐｒａ,1 93 1 ,Ｒ .ｂａｒｎａｒｄｉｉＳａｋａｉ,1 974 ,Ｒ .ｃｒｏｓｎｉｅｒｉＲｉｂｅｓ,1 989ａｎｄＲ .ｉｎｔｅｒｍｅｄｉｕｓＤａｉｅｔＸｕ,1 993 .ＲｅｃｅｎｔｌｙｒｅｐｏｒｔｅｄＲ .ｐｅｒｓｏ… 相似文献
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1 INTRODUCTIONRecently ,thepollutionoftracemetalinseawaterhasbecomeincreasinglyevident.Researchershavefo cusedattentiontotracemetalpresentinvariousexistenceforms ,especiallyorganiccomplexingphases.Theexistencestatesandtransportmechanismofbaytracemetalswerethesubjectofstudybysomere searchers(Gu ,1 991 ;Florence ,1 998;Guo ,1 998;Wells,1 991 ,1 998a ,b ;Wellsetal.,1 998) .Whetherinfreshwaterorseawater,colloidsareclearlydominantfactorsaffectingtheexistencestatesandtransportmechanismoftrac… 相似文献
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INTRODUCTIONFormanyyears ,environmentalfactorsinfluencingmicroalgagrowthhadbeenstudiedbymanyresearchers .Thesefactorsincludedtemperature ,light,nutrientcomposition ,tracemetalsandtheirtoxicity ,etc . (Rhee&Gotham ,1 981 ;Morel,1 987;Fujimotoetal.,1 997;Geideretal.,1 998) .Colloid ,animportantexistingformofmatterinseawater,alsohadbeenstudiedwidelyinre centyears.Itiswidelyknownnowthatcolloidservesasanoceanic“colloidpump” (Honeyman&Santschi,1 991 ) .Reviewsofthebasiccharacteristicsandpr… 相似文献
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INTRODUCTIONIntheearly 1 980 s,ventilationtheoryemergedtopredictthehorizontalandverticalstructureofthethermocline.Thereweretwodifferentviewsonthestratifiedoceans.Thefirsttheory (RhinesandYoung,1 982 ,hereafterRY ;YoungandRhines,1 982 )proposedanunventilatedmodelinwhichonlytheuppermostlayerisexposedtothesurfaceandisforcedbythewindstress.Thesecondtheory (Luytenetal.,1 983 ,hereafterLPS)offeredaventilatedmodelwhichisclosertotheclassicalthermoclinetheoriesthanthatofthefirstone (e.g .,Nee… 相似文献
13.
Toshitaka Suzuki Yoshinori Iizuka Teruo Furukawa Kenichi Matsuoka Kokichi Kamiyama Okitsugu Watanabe 《极地研究(英文版)》2003,14(1)
1 IntroductionAntarcticicesheetisaburialgroundforatmosphericdeposition .Sincethereiscon tinuousinteractionbetweentheicesheetandtheatmosphere,variousatmosphericsub stancesareinjectedtotheicesheetsequentiallyintimeandspace.Therefore,verticalanalysesoftheicesheetprovideuswithinformationaboutpastclimaticchange (Delmas1 992 ;LegrandandMayewski 1 997)andhorizontalanalysesoftheicesheetprovideuswithknowledgeregardinglong rangetransportofairbornematerials (Kamiyamaetal.1 989;KreutzandMayewski 1 999)… 相似文献
14.
林东年 《广东海洋大学学报》2001,21(4):63-65
为了促进对虾养殖业可持续发展 ,我们对养殖周期短、虾苗成活高、抗病力强的南美白对虾进行了普通池塘养殖、沙滩提水式养殖、高密度养殖、咸淡水养殖、淡化养殖等综合技术试验研究 ,经过一年多的试验研究与推广 ,获得了显著的效果。1 材料与方法1 .1 材料1 .1 .1 普通池塘养殖试验 池塘为泥质普通池塘 ,面积 0 .53 hm2的池塘试养南美白对虾 ,面积0 .67hm2 池塘养殖斑节对虾 ,水深均为 2 .0 m,1 999年 7月 2 3日投放体长 1 .0 cm南美白对虾苗1 2万尾和斑节对虾苗 1 3万尾 ,放苗密度分别为 2 2 .5万尾 /hm2 和 1 9.5万尾 /hm2 。1 .1 .2… 相似文献
15.
SEAWEED CULTIVATION: TRADITIONAL WAY AND ITS REFORMATION 总被引：4，自引：0，他引：4
INTRODUCTIONSeaweedcultivationisthemosteffectivewayforobtaininglargeamountofseaweedproducts.Thoughseaweedcultivationhasahistoryofonlyafewdecades,itsdevelopmentisfast (Fei,1 996) .Thetotalproductionofcultivatedseaweedatpresentisabout 62 50× 1 0 3tonsfreshweight,ofwhichLaminariaaccountsfor 3 1 0 0× 1 0 3tons,Undaria 2 2 0 0x 1 0 3tons,Porphyra 750× 1 0 3tons,Gracilariasp .1 0 0× 1 0 3tons,EucheumaandKappaphycus 1 0 0× 1 0 3tons,otherkindofseaweeds 1 0 0× 1 0 3tons.Theestimatedtotal… 相似文献
16.
INTRODUCTIONTidalchannelsareimportantgeomorphologicunitsalongsiltcoasts.Theyhaveanevidentfunc tionfortidalflatbecausetheyareassociatedwithitsrapidbayheadwarderosionandlateralswing ing.Thetidalchannelsdevelopalongthecoastandplayanimportantroleinseaandlandinterac tion .Manyscientistsresearchedthetidalchannels (Bayliss Smith ,1 978;Shao ,1 988;Zhang ,1 995) .TheScientificandTechnicalCommitteeofShandongProvince (1 991 )investigatedthecoastoftheHuanghe (Yellow)RiverDeltaandresearchedtheti… 相似文献
17.
1 GPSobservationanddataprocessingGPSobservationwasmadeforthefirsttimefromAugust 2 6toSeptember 6in 1 998at 2 5fidu cialstationsoftheCrustalMovementObservationNetworkofChina (markedwithcodesinFig .1andtherearestationnametranslationsinTab .1 ) .SincelateMarch 1 999theobservationhasbeenmadecon tinuouslyatasamplingintervalof 30sec .Duringa3 yearperiodofcontinuousGPSobservation ,therewereproblemsintheobservationdatacausedbyrainwaterleakageintheantennasandotherprob lemsatfiducialstationsTAI… 相似文献
18.
Qiao Xuejun ) Wang Qi ) Du Ruilin ) Chen Zongshi ) You Xinzhao ) Tan Kai ) ) Institute of Seismology China Earthquake Administration Wuhan China ) Second Crust Monitoring Application Center CEA Xi’an China ) Center for Analysis Predication CEA Beijing China 《大地测量与地球动力学》2003,23(Z1)
1 IntroductionTheBogedabanapexofKunlunmountainanditsneighborhoodregionlocatedattheboundaryofXinjiangandQinghaiprovinceswerehitbyaMs8.1earthquakeonNovember 1 4,2 0 0 1 .ThisisthestrongestearthquakewithmagnitudebiggerthanMs8.0inmainlandChinasinceacomparableearth quakehappenedinDangxiongofTibetonNovember1 8,1 95 1 .TheepicenterdeterminedbyChineseseismicnetworkislocatedatN36.2°,E90 .9°,40 0kilometersawayfromRuoqiangcountyofXinjiangprovinceand 35 0kilometersfromGolmudcityre spectively.Mea… 相似文献
19.
Biofouling is an important factor that affects the bivalve farming industry. Fouling organisms may reduce growth and survival rate of the cultured species. Fouler are often filter feeders, so they are potential competitors for food resource with the cultured species. The present study was conducted to measure the impact of fouling on food uptake and nutrient release in April and June, 2006 in Daya Bay near Guangzhou, China. Results showed that fouling organisms had significant effect on food uptake and nutrient release. The chlorophyll a uptake rate of fouled scallops was 7.53Lh-1±1.416Lh-1 and 11.94Lh-1±2.497Lh-1 in April and June, respectively, significantly higher than those of cleaned scallops, i.e., 4.23 Lh-1 ±2.744Lh-1 and 2.57Lh-1± 1.832 Lh-1 respectively.The consumption of total particulate matter by fouled scallops in April and June was 5.52Lh-1±0.818Lh-1 and 3.07Lh-1±0.971 Lh-1,respectively; the corresponding results for cleaned scallops are 2.49Lh-1 ±0.614Lh-1 and 2.37± 1.214Lh-1, respectively. Fouling increased ammonia release significantly. The ammonia release rate of fouled scallops was 33.81Lh-1±7.699Lh-1 and 76.39Lh-1 ±9.251Lh-1 in April and June, while cleaned scallops released 2.46Lh-1± 0.5 1 1Lh-1 and 7.23Lh-1± 1.026Lh-1 ammonia, respectively. Phosphate release of fouled scallops was 22.72Lh-1 ± 9.978 Lh-1 in June and cleaned scallops released phosphate 6.01Lh-1 ±0.876 Lh-1 in April. Therefore, fouling contributed much to food reduction and concentration increase of ammonia and phosphate in water. 相似文献
20.
The sea fluxes of trace metals, POC, and settled material were studied in anoxic sea water, Saanich Inlet, B.C., Canada with sediment traps. This paper discusses the change of mass fluxes of sediment, trace metals and POC for various seasons and depths. The annual mean of settled material is 1.56 g.m-2 .a-1, 84.6 mg. m-2. a-1 for POC, 60.0 mg.m-2. a-1 for Cu, 16.5 mg.m-2.a-1 for Pb, 189 mg.m-2. a-1 for Zn, 2.20mg.m-2.a-1 for Cd,699 mg.m-2.a-1 for Fe,38.8 mg.m-2.-1 for Co, and 84.6 mg.m-2.a-1 for Ni.The relations between the average fluxes of trace metals and POC, the fluxes of trace metals and settled matter, and the sea fluxes of trace metals and Fe are in linear progression. The resident times of elements as calculated from sea flux, are 1.1 a. for Cu, 0.014 a. for Pb, 0.50 a. for Zn, 3.8 a. for Cd, 0.16 a. for Fe, 0.39 a. for Co,and 1.14 a. for Ni.The order of resident times is as follows: Pb-Fe-Co-Zn-Cu-Ni-Cd. The metal resident times in Saanich Inlet are shorter than the values estimated for the op 相似文献