Post on 07-Jul-2020
Oaks/GrassSavannaAmeriFluxSiteinCalifornia
DennisBaldocchiSiyanMaandJoeVerfaillie
UniversityofCalifornia,Berkeley
ECOSTRESSMee?ng,UCDavis,May16,2017
Objec?ves
• GiveOverviewofResourcesandMetadata• Reportonfindingsfrom16+yearsofcon?nuouscarbon,waterandenergyfluxesmeasuredoverOaksavannaandannualgrassland
TonziRanch,US-Ton,AmeriFluxTower
Dis?nctWetandDryPeriods,toStudyEffectsofVaryingSoilMoistureonCarbonandWaterExchangeExperienceswiderangeofTemperature(0-40C),tostudyeffectsofWarmingonEcosystemProcessesExperienceswiderangeofAnnualPrecipita?on(300-1000mm),tostudynon-lineareffectsofrainfallonecosystemmetabolismOpenStructureChallengesassump?onsofSimpleBig-LeafModels
OakSavannaisPerfectLaboratoryforStudyingEcosystem-ClimateInterac?ons
Camp Pardee
ppt mm
200 400 600 800 1000 1200
Cou
nt
0
2
4
6
8
10
12
14
16
18
20
InterannualVariabilityofRainatTonzi/VairaRanches
We’veExperiencedAverageandExtremelyWetandDryYearsoverthepast16years2012/13weredrybutweexperiencedDryyearsbeforeOaksareadaptedtodryyearsandcansurvive2dryyearsinarow.Whatabout3dryyearsinarow?Theytendtooccurrarely.
Ione, CA
End of Hydrological Year
2000 2002 2004 2006 2008 2010 2012 2014 2016
Pre
cipi
tatio
n (m
m/y
)
300
400
500
600
700
800
900
1000
savanna
Griffin+Anchuka?s,2015GRL
Liu,Y.,M.J.Hill,X.Zhang,Z.Wang,A.D.Richardson,K.Huiens,G.Filippa,D.D.Baldocchi,S.Ma,J.Verfaillie,andC.B.Schaaf.2017.UsingdatafromLandsat,MODIS,VIIRSandPhenoCamstomonitorthephenologyofCaliforniaoak/grasssavannaandopengrasslandacrossspa?alscales.AgriculturalandForestMeteorology237–238:311-325.
ModisOperandi
• DirectCarbon,WaterandEnergyFluxMeasurementswithEddyCovariance
• Spa?alUpscalingwithRemoteSensing– TerrestrialandAirborneLIDAR,IKONOS(1-4mresolu?on)
• TemporalUpscalingwithDigitalCamerasandVegIndices– PhenologyandDynamicsofLeafAreaIndex
• Mechanis?cUnderstandingofEcophysiologicalProcesses– UnderstoryeddyfluxsystemandsoilCO2probesforfluxpar??oning– EcosystemModeling,CANOAK-3D– PhysiologicalMeasurementsofPre-DawnWaterpoten?aland
photosynthe?ccapacity,TRY– Soilmoisturenetworks,COSMOS,SMAP,ISMN– RootandSoilDepth,withGPR
EddyFluxInstrumenta?on
3dSonicAnemometerNonDispersiveInfraredGasSpectrometerforCO2andH2O
EddyCovariance
F w c= ' '
Mean
Fluctuation
RepositoryofRemoteSensingData• Ikonos:07/22/2001• Avris:2005,2006,2009• CASI:• AirborneLIDAR:2003,2009• TerrestrialLidar:2014• MODISTimeSeries…• UpwardLookingDigitalCamera?meseries:2006-• LED/NDVI?meseries:2006->• HighResolu?onspectralreflectance?meseries(2006-)• UnderstoryTramSystem(PARandRninx):2006-2015• Tower-basedDigitalWebCamera:2005->
TonziRanchOakSavanna,nearIone
IKONOS
CanopyStructure:LaserAl?meterData
Chenetal
LIDAR Measurements of Tree HeightOak Savanna, Ione, CA
Tree Height, m
0 10 20 30 40 50 60
0.0
0.1
0.2
0.3
0.4
2003, ave ht = 9.62 m2009, ave ht = 10.64 m
LIDAR, Oak Savanna, Ione, CA
Crown Diameter, m
0 5 10 15 20 25 30pd
f0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
2003: 8.06 m 2009: 8.79 m
Belandetal
MonitorSurfacePhenologywithaSuiteofOp?calSensors
LEDNDVISensor
FluxTowerwithDigitalCamera
Hyper-spectralspectrometerUpwardLookingCamera
GapFrac?onPhenologywithUpwardLookingCamerasunderOakSavanna
CanDetectStartandEndofGrowingSeasonwithPrecision
SoilDepthwithGroundPenetra?ngRadar
Raz-Yaseefetal,2013JGRBiogeoscience
Roots!
Oak Savanna 2005
Day
0 50 100 150 200 250 300 350 400
Soi
l Moi
stur
e ( c
m3/
cm3)
0
10
20
30
40
50
0-15 cm15-30 cm30-45 cm45-60 cm
SeasonalityofSoilMoisture
MonitoringDepthtoGroundWater
Maetal.2016AgForMetMilleretal,2010,WRR
Day
100 120 140 160 180 200 220 240 260 280
Vcmax
0
20
40
60
80
100
120
140
SeasonalityofPhotosynthe?cCapacity
InterannualVariabilityofNetEcosystemCarbonExchange
VairaRanch
TonziRanch
GrasslandisCarbonNeutral,aslightsource:27gCm-2y-1SavannaisamodestSink,:-157gCm-2y-1
Ione, CA
Hydrological Year
2000 2002 2004 2006 2008 2010 2012 2014 2016 2018
NE
E (g
C m
-2 y
-1)
-300
-200
-100
0
100
200
300
SavannaGrassland
EffectofDrought
2013wasNormalun?laboutD120,thenSystemshutdown,Physiologically
Savanna
Day
0 50 100 150 200 250 300 350
NE
E (g
C m
-2 d
-1)
-4
-2
0
2
4NEE Ave (2001-2013)2013
Varia?oninGrossPrimaryProduc?vity
Savanna(1060gCm-2y-1)wasmoreproduc?ve,by40%,thantheGrassland(665gCm-2y-1)
Ione, CA
Hydrological Year
2000 2002 2004 2006 2008 2010 2012 2014 2016
GP
P (g
C m
-2 y
-1)
400
600
800
1000
1200
1400
1600
Savannaannual grassland
Varia?oninEcosystemRespira?on
The‘cost’ofamoreProduc?veSystem
Ione, CA
Hydrological Year
2000 2002 2004 2006 2008 2010 2012 2014 2016
Rec
o (g
C m
-2 y
-1)
400
600
800
1000
1200
1400
oak savannaannual grassland
RainandEvapora?on SavannaET:404+/-64mmy-1AnnualGrassET:323+/-26mmy-1ppt:542+/-173mmy-1
Ione, CA
End of Hydrological Year
2000 2002 2004 2006 2008 2010 2012 2014 2016
Wat
er F
lux
(mm
/y)
200
300
400
500
600
700
800
900
1000
savannagrasslandprecipitation
On-GoingWork
WorkCon?nuesatpartofAmeriFluxandFLUXNETnetworksUseTerrestrialLidartoCharacterizeCanopyandApply3-dModelstoSimulateLight,carbonandWaterExchangeCollabora?ngwithCOSMOSandSMAPprojectsTodetectsoilmoisturedynamicswithremoteSensingandmicrowavebandradarDataareWidelyUsedinValida?ngModels,RemoteSensingProductsandCrossSiteSyntheses
LifeasaBlueOak:FirngthroughtheEvolu?onaryEye
oftheNeedle
Savanna vs Grassland
Savanna
400 600 800 1000 1200 1400 1600
Gra
ssla
nd
300
400
500
600
700
800
900
1000
1100
GPP; r2 = 0.53Reco; r2 = 0.72Plot 1 Regr
CarbonFluxesattheSavannaandGrasslandareinSynch
Year to Year Changes in Productivity
dGPP (gC m-2 y-1)
-600 -400 -200 0 200 400 600
dRec
o (g
C m
-2 y
-1)
-400
-200
0
200
400
600SavannaAnnual GrasslandPlot 1 RegrCoefficients:
b[0] 18.51b[1] 0.658r ≤ 0.727
YearsthatPromoteProduc?vity,rela?vetothePrioryearComeattheCostofMoreRespira?on,
AndViceVersa
ClimateTrends:Pardee,CA
TemperatureIncreasedbyabout1.25Cover60Years
Precipita?onisHighlyVariableandNeartheBorderlinetoSustainForestsvsGrass
Camp Pardee
Year
1920 1940 1960 1980 2000 2020
Tair
(c)
14.5
15.0
15.5
16.0
16.5
17.0
17.5
18.0
18.5
Camp Pardee
Year
1920 1940 1960 1980 2000 2020
annu
al P
reci
p (m
m)
0
200
400
600
800
1000
1200
mean: 518 mmstddev: 193
-124 -123 -122 -121 -120 -119 -118 -117 -116 -115Longitude
33
34
35
36
37
38
39
40
41
42
Latit
ude
Quercus douglasii Range
FieldSites,nearIone
BlueOakRange