冻融对湿地土壤可溶性碳、氮和氮矿化的影响

1,2,1,1,1,2,1(1.,130012;2.,100039):,(-55-255)(DOC)(DON),,DOCDON,DOC1(-55-255),DON2(-55)4(-255)DOCDON,-255-55,,,:;;;;;:X144:A:1673-4831(2008)03-0001-06EffectsofFreezingandThawingonDissolvedOrganicCarbonandNitrogenPoolandNitrogenMineralizationinTypicalWetlandSoilsFromSanjiangPlain,Heilongjiang,China.ZHOUWang2ming1,2,WANGJin2da1,LIUJing2shuang1,QINSheng2jin1,2,WANGYang1(1.InstituteofGeographyandAgriculturalEcology,ChineseAcademyofSci2ences,Changchun130012,China;2.GraduateUniversityofChineseAcademyofSciences,Beijing100039,China)Abstract:Contentsofdissolvedorganiccarbonandnitrogen(DOCandDON)andnitrogenmineralizationofwetlandsoilsdifferentinfreezingandthawingcyclewereinvestigatedthroughanindoorincubationexperiment.Resultsshowthatwiththenumberofthecyclesincreasing,DOCandDONroseupfirstandthendeclined.DOCpeakedafteronecycle,either-5to5or-25to5,whileDONdidaftertwocyclesof-5to5andfourcyclesof-25to5,whichindi2catesthattheeffectoffreezingandthawingalternationwithinashorttimeperiodwassignificantonDOCandDONinthesoil.Itwasalsoquiteobviousthatnitrogenmineralizationinthewetlandsoilwasaffectedbyfreezingtemperatureandnumberoffreezingandthawingcycles,andthesoilsundercyclesof-25to5werehigherthanundercyclesof-5to5inaccumulativenitrogenmineralization.Alternationoffreezingandthawingacceleratedsoilnitrogenmineralization,whichfacilitatedaccumulationofsoilavailablenitrogen,thusbuildingupanadequateNpooltomeetthedemandforNoftheplantgrowinginthespring,whichcontributessignificantlytomaintenanceofstabilityofthewetlandecosystem.Keywords:freezingandthawing;dissolvedorganiccarbon;dissolvedorganicnitrogen;nitrogenmineralization;wet2land;SanjiangPlain(dissolvedorganiccarbonornitrogen,DOCDON),[1]DOC[2];DON,,[3],,,,DOCDON,:(KZCX2-YW-309);(90211003):2008-03-042008,24(3):1-6JournalofEcologyandRuralEnvironment'1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.()[4]PURI[5],,[6],,,[7-9],,,,,,DOCDON,11.1(4735N,13331E),55.457.9m,1-18-21,72122,1.61.9,78,1m,101135[10],393.2543.263.6gkg-1,(42.11.5)gkg-1,C/N17.360156,pH5.610.13,1.21.2.120078,,015cm,4mm,,257d[(352.5116)gkg-1]100g,2,34d1,2:(1)-55-255,-5-251d,51d,10()124610,3DOCDON(NH+42N)(NO-32N)(2)-5-2514d,514d,31.2.210524hDOCDON:10g[V()m()=2.51],30min,4000rmin-110min,(0.45m),TOC2VCPH,-SKALAP(STN)(SIN),DON=STN-SIN[11]7g,30mL2molL-1KCL,30min,SKALAPNO-32NNH+42N[12]1.3(ANOVA),Excel2003Origin7.5SPSS11.522.12.1.1(1),(DOC),[8-9]2(-55-255),1,DOC,1.81.92,DOCDOC(1),4,DOC,(P0.05)(1)10,,2DOC9%28%,224©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.(1),,DOC1Fig.1Effectoffreezing2thawingalternationonconcentrationofdissolvedorganiccarboninsoil1(ANOVA)Table1ANOVAoftheeffectoffreezingtemperatureandnumberoffreezingandthawingcyclesondissolvedorganiccarboninsoilFP1610.9111641.911.770.20074374.78418593.6920.430.000E3409.724852.430.940.46516380.6618910.041916724.6628=0.05,R2=0.7432.1.2(DON)2,DON1,-55-255DON2.11.32,-55DON[(24.724.76)mgkg-1],-255DON4[(40.9727.51)mgkg-1]10,,-55-255DON38%169%-255DON-55,2,DON(2)-55,DON;-255,4DON(2)(2),DON2Fig.2Effectoffreezing2thawingalternationonconcentrationofdissolvedorganicnitrogeninsoil2(ANOVA)Table2ANOVAoftheeffectoffreezingtemperatureandnumberoffreezingandthawingcyclesondissolvedorganicnitrogeninsoilFP379.481379.482.580.13269.33467.330.460.77E716.294179.071.220.352061.5618147.2516375.1528=0.05,R2=0.0012.22.2.13-55,2;433:©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.[12]HERRMANN[13],-255-55,DELUCA[12](3),(P0.05)3Fig.3Effectofnumberoffreezing2thawingcyclesonsoilnitrogenmineralization3(ANOVA)Table3ANOVAoftheeffectoffreezingtemperatureandnumberoffreezingandthawingcyclesonsoilnitrogenmin2eralizationFP119.621119.6241.50.001516.195163.2356.60.001E56.7511.343.90.01257.66202.884046.732=0.05,R2=0.9152.2.244,5-55-255(26.24.97)(31.991.07)(38.922.98)mgkg-1,[(41800.63)mgkg-1](4),-2555(P=0.033),-55,HERRMANN[13]NIELSEN[14]4Fig.4Effectofdifferentfreezingtemperatureonsoilnitrogenmineralization,5-55-255,46.47189.7,89.43%89104%91151%;,32.542.992.92424©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.[10,15],[16-17],[10,17];,,,NH+[18]4,(393.2gkg-1)[10]33.1,[11]SCHIMEL[19],,,,,[20],DOCDON,,DOCDON,DOC1(-55-255),DON2(-55)4(-255)(1,2),DOCDON,13,DOC,6DOC[9]GROGAN[8],1DOCDON,DOCDON,,,[7]DOCDON1,,DOCDON[2]1,154-11-25-46,,,[7]-255-55,DOCDON,,DOCDON;,,DOCDON,DOCDON,CO2,,DOCDON[6,9,20]3.2,0,0,[12,14],,,,[12];,,,[13];,FREPPAZ[21],NH+42N,-255,-552,-55,,,N2O[22],,[20][14],,,(NH+4),NO-32N[8,14]NH+42N,,,,[14],,N2O[22],53:©1994-2009ChinaAcademicJournalElectronicPublishingHouse.Allrightsreserved.[14]4(1)DOCDON,DOCDON,DOC1(-55-255),DON2(-55)4(-255),DOCDONDOCDON1,,DOCDON(2),,,,,,,,,:[1],,,.[J].,2003,14(10):1809-1812.[2],.[J].,2004,41(4):544-552.[3],,.[J].,2005,26(6):1299-1305.[4]DENEVES,HARTMANNR,HOFMANG.TemperatureEffectsonNMineralization:ChangesinSoilSolutionCompositionandDe2terminationofT