简介：AftercompositingthreerepresentativeENSOindices,ElNioeventshavebeendividedintoaneasternpattern(EP)andacentralpattern(CP).ByusingEOF,correlationandcompositeanalysis,therelationshipandpossiblemechanismsbetweenIndianOceanDipole(IOD)andtwotypesofElNiowereinvestigated.IODevents,originatingfromIndo-Pacificscaleair-seainteraction,arecomposedoftwomodes,whichareassociatedwithEPandCPElNiorespectively.TheIODmoderelatedtoEPElNioevents(namedasIOD1)isstrongestatthedepthof50to150malongtheequatorialIndianOcean.Besides,itshowsaquasi-symmetricdistribution,strongerinthesouthoftheEquator.TheIODmodeassociatedwithCPElNio(namedasIOD2)hasstrongestsignalintropicalsouthernIndianOceansurface.Intermsofmechanisms,beforeEPElNiopeaks,anomalousWalkercirculationproducesstronganomalouseasterliesinequatorialIndianOcean,resultinginupwellingintheeast,decreasingseatemperaturethere;acoupleofanomalousanticyclones(strongerinthesouth)formofftheEquatorwherewarmwateraccumulates,andthustheIOD1occurs.WhenCPElNiodevelops,anomalousWalkercirculationisweakerandshiftsitscentertothewest,thereforeanomalouseasterliesinequatorialIndianOceanislessstrong.Besides,theanticyclonesouthofSumatrastrengthens,andthesoutherlieseastofitbringcoldwaterfromhigherlatitudesandnortherlieswestofitbringwarmwaterfromlowerlatitudestothe15°to25°Szone.Meanwhile,thereexistsstrongdivergenceintheeastandconvergenceinthewestpartoftropicalsouthernIndianOcean,makingseatemperaturefallandriseseparately.Therefore,IOD2liesfarthersouth.

简介：于2010年4月大潮日（14-15日）,连续24h采样,测定闽江河口潮汐沼泽土壤间隙水中的N2O含量,同时测定了土壤间隙水中的营养盐含量和水温等。土壤间隙水中的N2O摩尔质量浓度日变化范围为14.65-16.42μmol/L,平均值为（15.25±0.09）μmol/L,且白天高、夜晚低,但差异不显著;在涨潮阶段,土壤间隙水中的N2O含量较高,表明潮汐水会增加土壤间隙水中的N2O含量;土壤间隙水中的N2O含量与土壤温度、电导率显著负相关（n=25,p〈0.05）,与间隙水中的NH4＋—N、NO3-—N含量显著正相关（n=25,p〈0.01）。春季大潮日闽江河口潮汐沼泽土壤间隙水中的溶解性N2O含量日变化受土壤温度、盐度、间隙水中的营养盐含量和潮汐的综合影响。