草地植被變化遙感監(jiān)測(cè)方法研究——以環(huán)青海湖地區(qū)為例.pdf

1、南京師范大學(xué)博士學(xué)位論文草地植被變化遙感監(jiān)測(cè)方法研究——以環(huán)青海湖地區(qū)為例姓名：查勇申請(qǐng)學(xué)位級(jí)別：博士專業(yè)：地圖學(xué)與地理信息系統(tǒng)指導(dǎo)教師：倪紹祥2003.5.1ResearchontheRemoteSensingMeansofMonitoringGrasslandVegetationChange：ACaseStudyoftheAreaaroundLakeQinghaiZHAYong(SchoolofGeographicscience，N

2、鋤jingNormalUniversity，Nanjing210097，China)Abstract：InthisstudyaquantitativemethodofdirectlyestimatingparametersindicativeofgrasslandvegetationchangefromexistentLandsatThematicMapper(TM)imagedataandunifiedmodelsfortheesti

3、mationinastudyareaaroundLakeQinghaiofQinghaiProvince，Chinaweredevelopedusingmodemsatelliteremotesensingtechnology，inconjunctionwithinsitugrasslandsamplesconcurrentlycollectedwithsatellitedatarecording，groundremotesensing

4、，aswellasGlobalPositioningSystem(GPS)technologyInvariantgroundtargetswereusedtomdiometricallycalibratehistoricalimagedataandtostandardizemultitemporalsatellitedataThesecalibrateddatawereinputintoaGIStodetectthespatiotemp

5、oralchangesofgrasslandvegetationinthestudyareaSuchdetectedchangeswerecomprehensivelyanalyzedinassociationwitlawidevarietyofnaturalandsocioeconomicfactorsthatmightaffectgrasslandvegetationchangesinanattempttodetermineitsm

6、echanismThisstudyhasledtothefollowingfindingsandconclusions：(1)Densityofgrasscoverandtheproportionofpalatablespeciesofgrassinthestudyareaaremostcloselycorrelatedwithnormalizeddifferencevegetationindex(NDVI)andsoiladjuste

7、dvegetationindex(SAVI)，respectivelyTheirregressionmodelstakethefollowingform：Densityofgrasscover=21057xNDVI一47915(RkO74)Proportionofpalatableglassspecies=31811xSAVI一5213fR2=073)Fieldtestssuggestthattheoverallaccuracyofes

8、timatingtheseparameterswasashighas89％and87％respectively(2)Incasethatgrasscoverdensityisnotspatiallyhomogeneousonthegroundandthatinsitusamplingplotsaremuchsmallerthanthosefromspace，itisimpossibletoestablishanaccurateregre

9、ssionrelationshipbetweeninsitusampledparametersandthevalueoftheircorrespondingpixelsonthesatelliteimageasisthecaseintheconventionalwayinthepastInthisstudyIundertookthecalibrationoftheTMimagefirstwiththeresultsacquiredfro