22961.兩種根蘗型植物的根系構型對典型草原退化演替的生態(tài)適應性研究

1、分類號Q948.1UDC632學校代碼10129學號08204056兩種根蘗型植物的根系構型對典型草原退化演替的生態(tài)適應性研究StudyofEcologicalAdaptationofRootArchitectureofTwoCreepingrootedPlantstoDegradationSuccessionintheTypicalSteppe申請人：周艷松學位名稱:農(nóng)學學科專業(yè)：野生動植物保護與利用研究方向：野生植物保護與利用指導教

2、師：王立群教授論文提交日期：二○一一年六月StudyofecologicaladaptationofrootarchitectureoftwocreepingrootedplantstodegradationsuccessioninthetypicalsteppeAbstractCreepingrootedplantsplayanimptantroleintheprocessofsteppedegradation.Thesteppesw

3、ithdifferentdegradationlevel(LMHE)attypicalsteppeinXilingolofInnerMongoliawereedparametersincludingthesoilmoisturesoilbulkdensitysoilhardnessplantcommunitywereinvestigated.Parametersofcreepingrootedplants(Potentillabifur

4、caPotentillaacaulis)noncreepingrootedplants(including8specieswithdifferenttypesofroot—axisrootedtyperhizometypedenseclustertypefibrousroottype)werecompared.Theparametersincludes11rootarchitectureindexesrootwidthrootdepth

5、withbelowgroundbiomassetal.Theresultswereshownasfollow:Firstamong11parametersofrootarchitecturerootsurfaceareahadthestrongestabilitytoexplainthecomprehensiveadaptabilitytosoilenvironmentoffivetypesofrootarchitecturefollo

6、wingthetotalrootlengthtotalrootvolumethenumberoffurcations.Secondrootswithadiameterof3.0to3.5mmhadasignificanteffectonrootsurfaceofP.bifurca.Rootswithadiameter1.5mmhadasignificanteffectonrootsurfaceofP.acaulis.Thirdtheth

7、reedimensionalrootarchitectureofabroadwaistinvertedcentrumwasanadvantageousconfigurationfP.acaulistoadapttosteppedegradationcanexplainitasaconstructivespeciesinextremelydegradedsteppe.Researchresultsshowedthat:withthedev

8、elopmentofsteppedegradationtheimptantvaluerelativedominanceofcreepingrootedP.bifurcaP.acaulisincreasedgraduallytheecologicalfunctionofthattwoplantsbecamememeimptantincommunitiesoftypicalsteppe.Thisphenomenonshowedthecree