简介:ToinvestigategeneticdiversitiesamongtheAAgenomeOryzaspeciesintheSoutheastandSouthAsia,atotalof428accessionsoftheAAgenomeOryzaspeciesweregenotypedusing36simplesequencerepeats(SSR)markersdistributedthroughoutthericegenome.Allofthe36SSRmarkersgeneratedpolymorphicbands,revealing100%polymorphism.Thenumberofallelesperlocusrangedfrom3to17withthemeanof8.6.TheNei’sgeneticdiversityindex(He)rangedfrom0.337atRM455to0.865atRM169withanaveragevalueof0.650.ThegeneticdiversityoftheAAgenomeOryzaspeciesintheSoutheastAsiawasobviouslyhigherthanthatintheSouthAsia.AmongthedetectedOryzaspeciesintheSouthandSoutheastAsia,O.rufipogonshowedthehighestgeneticdiversity.Meanwhile,ahighergeneticdifferentiation(Fst)wasfoundamongthedetectedOryzaspeciesintheSoutheastAsiathanintheSouthAsia.TheFstvaluebetweenO.nivaraandO.sativawasthehighest.Theresultsfromthenumberofspecificalleles,specificloci,andallelefrequencyconfirmedthegreatergeneticvariationamongthedetectedspecies.Inaddition,thespecificalleleinRM161displayedhigherfrequency(0.193),suggestingitsimportantfunctioninidentifyingOryzaspeciesofAAgenome.
简介:ThepentadaverageminimumoutgoingIongwaveradiation(OLR)dataoverthenorthernSouthChinaSea(SCS)areselectedasindexestoanalyzetheintensityoftheconvectionconnectedwiththeSCSmonsoononset.StatisticanalysisdemonstratesthattheindexcanaccountfortheintensityoftheSCSmonsoonabout,atleast,75%.Asignificantnegativecorrelation(confidentlevelover90%)betweenShandong'ssummerrainfallandtheindexisfoundonlyintheperiodof24-26pentadsandlimitedtotheareaabovethedeeperwaterbasinoftheSCS(10°-20°N,110°-117.5°E).ThustheminimumOLRoverthedeeperwaterbasinduring24-26pentadscanbeusedasavaluablepredictorforthelong-leadforecastoftheprecipitation.The500hPageopotentialheightdataintheNorthernHemispherefortheperiodfrom1951to2000areusedinordertocharacterizethephysicalmechanismsinvolved.Thecompositeanomaliesofthe500hPalevelallowfortheidentificationanddetectionoftheteleconnectionoftheEastAsia-NorthAmerica(EAP)patternthatisresponsibletosomeextentfortheinterannualvariabilityoftheprecipitationofShandongProvince.Besides,theinterannualdifferencesoftheintraseasonalvariations(ISV)ofOLRandtheirnorthwardtransmissionprobablymakeacontributiontothepositionofthesubtropicalhighwhichisvitalforthesummerrainfallintheprovince.
简介:Almosthalfoftheoceanicwatercolumnsexhibitdouble-diffusion.Theimportanceofdouble-diffusioninglobaloceans'saltandheatfluxes,water-massformationandmixing,andcirculationisincreasinglyrecognized.However,suchanimportantphysicalprocessintheoceanhasnotbeenwellstudied.Oneofthereasonsisthedifficultyofparameterizingandquantifyingtheprocesses.Thepaperpresentedhereattemptstoquantifythedouble-diffusivefluxesofsaltandheatintheocean.Previousqualitativeanalysisbyapplyingthewater-massTurnerangle,mTu,totheNorthPacificIntermediateWater(NPIW)layershowedafavorableconditionforsalt-fingeringintheupperNPIWduetotheoverlyingwarm/saltywaterabovethecold/freshNPIWcore,andadoubly-stableconditioninthelowerNPIWwherepotentialtemperaturedecreaseswithdepthwhilesalinityincreases,inducingdoublestratificationwithrespecttobothpotentialtemperatureandsalinity.Thepresentstudygivesaquantitativeestimateofdouble-diffusivefluxesofsaltandheatcontributedbysalt-fingeringintheupperNPIWlayer.
简介:ThelocationandlateQuaternaryactivityoftheCentral-NorthSegmentoftheTaihangMountainsPiedmontfaultzonehavebeenstudiedbyshallowseismicsurveyandcombineddrillexploration.OurresultsshowthattheBaoding-ShijiazhuangfaultandtheXushuifaultwereactiveinthelatePleistocene,butthesouthXushuifaulthasbeeninactivesincethelatePleistocene.Themaximummagnitudeofpotentialearthquakeofthefaultsis6.0.
简介:我们评估了在北伊朗在里海附近在Tavalesh区域影响大米鱼耕作的采纳的因素。我们与无限制的问题进行了调查。数据随机从184个回答者(61个采用者和123非采用者)被收集从选择村庄取样了并且分析了使用逻辑回归和多反应分析。家庭尺寸,与一个扩展代理人的接触的数字,在扩展教育活动的参予,在社会机构的会员和农场工人的存在是为大米鱼耕作系统的采纳的最重要的社会经济的因素。另外,经济问题是采用者报导的最普通的问题。象存取的缺乏那样的另外的问题捞食物拨出,鱼的损失,高质量的鱼鱼种和脱水和差的水质量的存取的缺乏对很多个农民也重要。
简介:DISTRIBUTIONOFLOWFREQUENCYWAVESINNORTHPACIFICANDINTRASEASONALABNORMALITYOFTHEWESTERNPACIFICSUBTROPICALHIGHLiXingliang(李兴亮)(Me...
简介:Lomagundi-Jatuli事件(LJE)是保存13C在在世界范围的Paleoproterozoic碳酸盐的+5和+16之间的carb价值。然而,这些旅行的持续时间,振幅和模式仍然保持糟糕抑制了。在北方中国Craton的2.14-1.83GaHutuo组是一>10km厚火山--沉积顺序,包括>5km在在上被扔的厚保存得很好的碳酸盐--对亚tidal环境潮汐。碳酸盐的152件最不改变的样品的公司同位素、元素的分析揭示了三阶段的13C进化。它以只积极的13Ccarb(+1.3到+3.4)在Dashiling和Qingshicun形成在~上演2.1Ga碳酸盐,从积极价值由转变列在后面到震荡在~的积极、否定的价值3000mWenshan,Hebiancun,Jianancun,和Daguandong形成的厚碳酸盐,并且与只否定的13C保存在的carb价值>500mHuaiyincun和Beidaxing形成的厚dolostones。看来许多LJE,特别地那些极其积极的13Ccarb信号,没在Hutuo碳酸盐被记录。只积极的13Ccarb价值(+1.3到+3.4)多半在更低的形成保存了对应于LJE的目的,而随后二个阶段反映LJE和Shunga-Francevillian事件(SFE)的发作的余殃。现在的数据点到碳上的氧的增加的影响从Doucun骑车到Dongye亚群并且证明在北方中国Craton的LJE的结束与在Fennoscandia和南非的那些是将近同时的。
简介:ThecropmodelWorldFoodStudies(WOFOST)wastunedandvalidatedwithmeteorologicalaswellaswinterwheatgrowthandyielddataat24stationsin5provincesofNorthChinafrom1997to2003.Theparameterizationobtainedbythetuningwasthenusedtomodeltheimpactsofclimatechangeonwinterwheatgrowthforallstationsusinglong-termweatherdatafrom1950to2000.Twosimulationsweremade,onewithallmeteorologicaldata(rainfed)andtheotherwithoutwaterstress(potential).Theresultsindicatethatthefloweringandmaturitydatesoccurred3.3and3daysearlierinthe1990sthanthatinthe1960sduetoa0.65℃temperatureincrease.Thesimulatedrainfedyieldsshowthattheaveragedroughtinducedyields(potentialminusrainfedyields)havedecreasedby9.7%overthelast50years.Thisistobecomparedwitha0.02%decreaseinyieldiftheprecipitationlimitislifted.Althoughtheprecipitationduringthegrowingseasonhasdecreasedoverthelast50years,thedroughteffectsontherainfedyieldsremainedtobepracticallyunchangedasthespringprecipitationdidnotdecreasemarkedly.
简介:Thisstudyfocusesonthedecadalvariabilityoftropicalcyclones(TC)overtheWesternNorthPacific(WNP)andhowthesechangesarerelatedtotheMadden-JulianOscillation(MJO).ItwasdonewiththehelpoftheReal-timeMultivariateMJOindexfromtheAustralianGovernmentBureauofMeteorologyoftheCentreforAustralianWeatherandClimateResearch,TCdatafromtheJointTyphoonWarmingCenterbesttrackdatasets,anddailyandmonthlydatasetsfromtheNCEP/NCARreanalysiscenter.TheresultsshowthattheTCfrequencyintheWNPexhibitedastatisticallysignificantdecreaseduring1998-2010comparedtoduring1979-1997.ThedecreaseinTCfrequencyintheWNPmainlyoccurredduringMJOactivephases(i.e.,phases4,5,6,and7).FurtherinvestigationoftheclimatebackgroundandthepropagationdifferencesoftheMJObetween1979-1997and1998-2010wasperformed.TheLaNina-liketropicalseasurfacetemperaturecoolingcausedstrongerWalkercirculationandthusinducedunfavorableatmosphereconditionsforWNPTCgenesisincludingalow-leveleasterlyanomaly,anegativerelativevorticityanomaly,anincreaseinsea-levelpressure,andstrongerverticalwindshear.Moreover,shorteningoftheMJOcycle,declineinthedurationoftheactivephasesintheWNP,andeasterlyanomalyandshrinkageoftheconvectionareaduringMJOactivephasesmayalsopartlyexplainthedecadalvariationofTC.
简介:PrecipitationobservationscollectedatweatherstationsineasternChina,theNCEP/NCARreanalysisdata,thetropicalcyclone(TC)BestTrackDataset,andasensitivitynumericalexperimentwereusedinthepresentstudytoinvestigatetheroleintheEastAsiansummermonsoon(EASM)systemplayedbyfrequentTCactivitiesoverthewesternNorthPacific(WNP).Resultsindicatedthat,inactiveTCyears,theEASMisstrongerandthesoutherlywindsinthelowertroposphereadvancefarthernorthandreachhigherlatitudes.Meanwhile,themonsoonrainbeltremainsinthelowerandmiddlereachesoftheYangtzeRivervalleyforarelativelyshortperiod,leadingtolessprecipitationthere.BoththewesternPacificsubtropicalhighandtheSouthAsianhighweakenwiththenorthwardshiftoftheridgelinesforbothhigh-pressuresystemsaswellastheEastAsiansubtropicalupper-leveljet.Therefore,theimpactsoffrequentTCactivitiesovertheWNPoneachindividualcomponentoftheEASMareinphasewiththoseofthestrongerEASMitself,amplifyingfeaturesofthealreadystrengthenedEASM.
简介:ThepolicyoftheChinesegovernmentconcerningthehorizontalexpansionofthecultivatedlandthroughthereclamationofdesertsoilsresultinatotalincreaseof665.985km2duringtheperiod1987-1999inNorthShaanxi.Thisincreaseislessthanthelossinarablelandbyurbanization.Theacceleratedrateofchangeinagriculturalareascallsformorerapidsurveysofurbanizationandlossofarableland.Remotesensinghasanumberofadvantagesoverground-basedmethodsforsuchsurveys.Themulti-scaleconceptofremotesensingdatahelpusstudytheprobleminfourtowns.Severalmapswereproducedtoanalyzethesituationofurbancoverageindifferenttimes.Theevaluationofthestatus,rateandriskofurbanizationarebasedonanacceptedaverageofurbanincreaseas2%ofpopulationgrowthperyear.
简介:Usingthehigh-qualityobservedmeteorologicaldata,changesofthethermalconditionsandprecipitationovertheNorthChinaPlainfrom1961to2009wereexamined.Trendsofaccumulatedtemperatureandnegativetemperature,growingseasonduration,aswellasseasonalandannualrainfallsat48stationswereanalyzed.Theresultsshowthattheaccumulatedtemperatureincreasedsignificantlyby348.5℃dayduetoglobalwarmingduring1961-2009whiletheabsoluteaccumulatednegativetemperaturedecreasedapparentlyby175.3℃day.Thestartofgrowingseasondisplayedasignificantnegativetrendof-14.3daysduring1961-2009,buttheendofgrowingseasondelayedinsignificantlyby6.7days.Asaresult,thelengthofgrowingseasonincreasedby21.0days.Theannualandautumnrainfallsdecreasedslightlywhilesummerrainfallandsummerrainydaysdecreasedsignificantly.Incontrast,springrainfallincreasedslightlywithoutsignificanttrends.AlltheresultsindicatethatthethermalconditionswereimprovedtobenefitthecropgrowthovertheNorthChinaPlainduring1961-2009,andthedecreasingannualandsummerrainfallshadnodirectnegativeimpactonthecropgrowth.ButthedecreasingsummerrainfallwaslikelytoinfluencethewaterresourcesinNorthChina,especiallytheundergroundwater,reservoirwater,aswellasriverrunoff,whichwouldhaveinfluencedtheirrigationofagriculture.
简介:TheGarouaZoneinNorthCameroon,thesubjectofthisstudy,isknowntohaveundergonetectonicmovementsduringtheCretaceous,butthezone’sstructuraldataremainpoorlyknown.ThisstudyexploitstheBougueranomalytoimproveknowledgeofGarouatectonicsstructures.Inordertocharacterizethesestructures,twomethodsareused:Euler’sdeconvolutionmethodandthemethodofthehorizontalgradientoftheverticalderivative.SuperpositionoftheEuler’ssolutionsmapforindexN=1withthemapfromthehorizontalgradientoftheverticalderivativemethodallowsdeterminationofgravimetriclineaments,interpretedasfaultsoraslinearcontacts,fromwhichwededuceastructuralmapofthestudyarea.Basedonthismap,weidentifysixteenlineaments,ofwhichwecounteightaslinearcontactsandeightasfaults.Amongthefaults,wedenoteoneofdepthbetween4and8km,fivefaultsofdepthrangingbetween8and13km,andtwofaultsofdepthsbetween13and36km.Analysisofthesefaultsshowsthatthesevendeepestfaultsmightpresentanaturalriskinourstudyarea.Forpurposesofcivilprotection,suchdeepfaultsshouldbemonitoredandtakenintoconsiderationintheimplementationoflargepublicworks.Thestructuralmap,establishedhereinfromdataonthein-depthextensionofeachfault,thusincreasesscientificknowledgeintheareathatcanbeusedtositepublicworksinwaysthatreducerisk.
简介:Nitrogen(N)lossesfromammoniumbicarbonateorureaappliedtowheatandthenfollowedimmediatelybyirrigationwereinvestigated.Ammoniavolatilizationwasdeterminedbyamicrometeorologicalmethod(ammoniasampler),totalNlosswasestimatedbythe^15Nmassbalancemethod,anddenitrificationlosswasmeasuredbythediferencemethod(calculatedfromthedifferencebetweenthetotalNlossandammonialoss)andadirectmethod(measuringtheemissionof(N2+N2O)-^15N).Totalammonialossesfromammoniumbicarbonateandureain33dayswere8.7%and0.9%oftheappliednitrogen,respectively.ThecorrespondingtotalNlosseswere21.6%and29.5%,Apparentdenitrificationlosses(bythedifferencemethod)wereratherhigh,being12.9%fromammoniumbicarbonateand28.6%fromurea.However,noemissionof(N2+N2O)-^15Nwasdetectedusingthedirectmethod.