Application of remote sensing techniques at different scales of observation on wetland evapotranspiration

182 Pages·2001·6.8 MB·English

by  Juan, Chung-hsin, 1968-

APPICATIONOFREMOTESENSINGTECHNIQUESAT
DIFFERENTSCALESOFOBSERVATIONON
WETLANDEVAPOTRANSPIRATION
By
CHUNG-HSINJUAN
ADISSERTATIONPRESENTEDTOTHEGRADUATESCHOOL
OFTHEUNIVERSITYOFFLORIDAINPARTIALFULFILLMENT
OFTHEREQUIREMENTSFORTHEDEGREEOF
DOCTOROFPHILOSOPHY
UNIVERSITYOFFLORIDA
2001
Dedicatedtomyparents
Chun-ChangandHua-Yin
ACKNOWLEDGMENTS
First,Iwouldliketoexpressmydeepestgratitudetomyformeradvisor,thelate
Dr.Sun-FuShih,andcurrentadvisorJonathanD.Jordanfortheirguidance,support,and
patience. Dr.ShihpassedawaysuddenlyonJune16,2000,whichwasatragiclossfor
hislovingfamilyandhisstudents. IfeelmournfulthatDr.Shihcouldn’tsharemyjoyat
theculminationofmyPh.D.studyjourney.
IalsogreatlyappreciateDr.AllenOverman,Dr.ByronRuth,Dr.MarkT.Brown,
andDr.BonDewittforservingonmygraduatecommittee,providingknowledgeand
precioussuggestions.
ManypeoplehelpedandcontributedtothisPh.D.research. Iamthankfulto
everyoneattheCenterforRemoteSensingwhoeverworkedwithme. Thelabmanager,
OrlandoLanni,wasgenerouswithhistimeandexperience;formergraduatestudents,
Chih-HungTan,Lei-WenChen,andcurrentgraduatestudent,JohnCraig,offeredgreat
assistanceinmanyfieldtrips. Currentgraduatestudents,AssefaMelessa,Kai-JenTien,
andKeng-LiangHuang,encouragedandinspiredmeinresearch. Iwouldalsoliketo
thanktheSt.John’sRiverWaterManagementDistrictforinstallationofthelysimeter
system,collectingsomedata,andpartiallysponsoringtheresearch,especiallythegreat
assistancefromDr.MariaMaoandKenSnyder. Ialsowanttoexpressmygreat
appreciationtotheInstituteofTechnologyDevelopment,StennisSpaceCenter,NASA
forprovidingaccesstothehyperspectralimager.
Moreover,Iwouldliketoacknowledgeaveryimportantpersonduringthese
yearsofgraduatestudyinUnitedStates,mybestfriendinGainesville,PhillipM.
Whisler.Wesharethesincerestfriendshipwithallmyjoysandsorrows. Withhis
friendshipIwasabletogetthroughmanyfrustratingmoments. Healsohelpedmewith
editingandproofreading thisdissertation.
Finally,Iexpressmydeepestgratitudetomyparentsfortheirmanyyearsoflove,
support,andencouragement.
IV
8
TABLEOFCONTENTS
page
ACKNOWLEDGMENTS
iii
LISTOFTABLES viii
LISTOFFIGURES x
ABSTRACT xiii
CHAPTERS
1 INTRODUCTION 1
1.1 ImportanceofWetlandEvapotranspiration 1
1.2 ApplicabilityofConventionalETMethodstoWetlandET 1
1.3 LimitedFieldStudyforWetlandET 2
1.4 ConventionalRemoteSensingApplicationonETEstimation 3
1.5 ImportantVegetationParametersforETEstimation 4
1.5 ProblemsinWetlandVegetationMapping 7
1.6 GoalsandObjectives 8
2 LITERATUREREVIEW 11
2.1 EvapotranspirationTheories 11
2.1.1 EnergyBalanceApproach 12
2.1.2 AerodynamicVaporTransportApproach 14
2.1.4 Penman-MonteithEquationandVegetationInfluenceonET 1
2.1.5 WaterBudgetandLysimeter 21
2.1.6 WetlandETStudies 22
2.2 RemoteSensingTechniques 24
3 MATERIALSANDMETHODOLOGY 33
3.1 StudySiteDescription 33
3.2 FundamentalStudyofWetlandET 36
3.2.1 VegetationParametersMeasurements 36
3.2.2 EstimationofCanopyResistance 42
3.2.2.1 Revisedprocedureofmeasuringstomatalresistance 43
3.2.2.2 RevisedprocedureofmeasuringLAI 43
v
1
3.2.4
MethodsforEvapotranspirationEstimation 43
3.2.4.1 ModifiedFAOPenmanmethod 44
3.2.4.2 Priestley-Taylormethod 46
3.2.4.3 Penman-Monteithcombinationmethod 47
3.3 SpectroradiometryontheResponsesofVegetationParameters 48
3.3.1 MonitoringofSpectralResponses 48
3.3.2 SpectralAnalysisofStomatalResistance 5
3.3.3 SpectralAnalysisofLAI 52
3.4 AerialHyperspectralImaging 53
3.4.1 PreparationsBeforeAerialImaging 55
3.4.1.1 Preparationofgeolocationtargets 55
3.4.1.2 Preparationofcalibrationpanels 56
3.4.2 SetupforAerialHyperspectralImaging 57
3.4.3 GroundTruthing 57
3.4.4 HyperspectralImageProcessingandCalibration 60
3.4.4.1 Geometricrectification 60
3.4.4.2 Radiometriccalibration 61
3.4.5 VegetationMappingUsingAerialHyperspectralImage 63
3.4.5.1 Testofcontingencyfortheselectionofdecisionrules 64
3.4.5.2 Testofseparabilityfortheselectionofthemosteffectivewavebands...64
3.5 ApplicationofSatelliteImages 66
3.5.1 SpectralCalibrationofETM+Images 67
3.5.1.1 Calculationofspectralradiance 67
3.5.1.2 Calculationofat-satelliteplanetaryreflectance 68
3.5.1.3 Calculationofat-satellitetemperature 69
3.5.2 VegetationMappingUsingETM+Images 70
3.5.2.1 SpectralanalysisofdifferentvegetationtypesontheETM+image 70
3.5.2.2 Knowledgebasedclassification 71
3.6 AccuracyAssessmentofVegetationMaps 72
3.7 EstimationofETovertheFortDrumMarsh 74
4 RESULTSANDDISCUSSION 75
4.1 Fun1d.4a.m4entalStudyofWetlandET 75
4.1.1 ConditionsoftheLysimeters 75
4.1.2 VegetationParameterMeasurements 76
4.1.3 EstimationofCanopyResistance 80
4.1.4 MethodsforEvapotranspirationEstimation 86
4.1.4.1 CorrelationsbetweenweatherparametersandET 89
4.1.4.2 EvaluationoftheETMethodsforsawgrass 90
4.1.4.3 EvaluationoftheETmethodsforcattail 94
4.1.4.4 OverallevaluationofdifferentETmethods 98
4. VerificationofdifferentETmethods 102
4.2 SpectralRadiometricAnalysis 103
4.2.1 SpectralResponseofDifferentVegetationTypes 103
4.2.2 SpectralResponsesofDifferentStomatalResistance 110
4.2.3 SpectralResponsesofDifferentLAIValues 116
vi
4.3 HyperspectralImaging 119
4.3.1 GeometricRectification 119
4.3.2 RadiometricCalibration 119
4.3.3 VegetationMappingUsingtheAerialHyperspectralImage 125
4.4 ApplicationofSatelliteImages 131
4.5 AccuracyAssessmentofVegetationMaps 136
4.6 EstimationofETovertheFortDrumMarsh 139
5 CONCLUSIONANDRECOMMENDATION 141
5.1 Conclusion 141
5.2 RecommendationforFutureResearch 143
APPENDICES
A WEATHERDATA 145
B ALBUMOFFIELDWORK 157
LISTOFREFERENCES 161
BIOGRAPHICALSKETCH 166
vii
LISTOFTABLES
Table Page
3.1 SpectralregionsofdifferentwavebandsintheLandsat-7ETM+scanner 51
3.2 Typicalerrormatrixdisplayforaccuracyassessment 73
4.1 Vegetationparametersforsawgrassinsevenfieldtrips 77
4.2 Vegetationparametersfor cattailinsevenfieldtrips 78
4.3 CorrelationcoefficientsofweatherparametersandETvalues 89
4.4 Correlationcoefficientsbetweentheweatherparameters 89
4.5 AnnualmeanETandRMSEofdifferentestimationmethodsforsawgrassin
1997 94
4.6 AnnualmeanETandRMSEofdifferentestimationmethodsforcattail
in1997 98
4.7 MonthlyestimatedandlysimeterETin1997 99
4.8 AnnualmeanETandRMSEofdifferentETmethodsin1999 102
4.9 ComputedNDVIofsawgrassandcattailfromspectralmeasurementsin
eachfieldtrip 110
4.10 Differentvegetationindicesatdifferentstomatalresistancevalues
(sawgrass) 115
4.11 Differentvegetationindicesatdifferentstomatalresistancevalues
(cattail) 115
4.12 VegetationindicesofsawgrassatdifferentLAIvalues 116
4.13 VegetationindicesofcattailatdifferentLAIvalues 116
4.14 KnowledgerulesforclassificationofwetlandvegetationusingtheETM+
images 132
viii
4.15 Matrixofaccuracyoftheclassificationusingthehyperspectralimage 137
4.16 MatrixofaccuracyoftheclassificationusingtheETM+images 138
IX
11
LISTOFFIGURES
Figure Page
1.1 Illustrationofthescaling-upconcept 9
2.1 Resistancemodelwithincanopy(adaptedfromMonteith&Unsworth,
1990) 19
2.2 Typicalspectralreflectancecurvesforvegetation,soil,andwater(adapted
fromLillesand&Kiefer,1994) 27
2.3 Reflectedspectrafordifferentcombinationofchlorophyll,anthocyanin.
(adaptedfromSwain&Davis,1978) 28
2.4 Averagecourseofreflectance,absorption,andtransmittanceofagreen
healthyplantleaf(adaptedfromdeBoer,1993) 29
2.5 Spectralreflectancecurvesoffouragriculturalcrops(adaptedfromde
Boer,1993) 31
2.6 Changesinthespectralreflectanceofoakleavesduringthegrowingseason
(adaptedfromdeBoer,1993) 1
3.1 Locationoftheexperimentalsite,(adaptedfromMao&Berman,1999) 34
3.2 LocationoflysimetersandFortDrummarsh(Mao&Berman,1999) 37
3.3 Desiredaerialhyperspectralimagingarea(theyellowsquare) 54
3.4 Spectralreflectanceofthecalibrationpanels 58
3.5 Possibleclassesintheaerialhyperspectralimagingareaaccordingtothe
1999 aerialimageofthesameflyoverpath 59
3.6 Atmosphericabsorptioneffectsespeciallyatsomeparticularwavelengths
(adaptedfromErdas,1995) 62
4.1 Stomatalresistanceofsawgrassversusheight 8
4.2 Stomatalresistanceofcattailversusheight 82
x