evaluation of high resolution data for lcluc science...3.green 4.yellow 5.red 6.red-edge 7.nir1 %...
TRANSCRIPT
Evaluation of High Resolution Data for LCLUC Science
PI Name: S. Skakun
Project Title: Combined use of VHR WorldView-2/3 and Planet datasets forMuSLI agricultural monitoring
Affiliation: University of Maryland, College Park
Co-I Name: J.-C. Roger
Affiliation: University of Maryland, College Park
Co-I Name: E. Vermote
Affiliation: NASA GSFC
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Objectives
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• To evaluate VHR data (1-3 m) on capturing a field level yield variability
• To explore the benefits of VHR data (1-3m) on crop mapping:• small fields with large diversity of summer crops in Ukraine, and
• mixed and small fields in Africa
• Expected data usefulness and benefits
Data Requested and Status
• Study Region:• US (Iowa), Ukraine (Western Part)
and Tanzania
• Data download status and plans:• US, Iowa
• WorldView-3 (WV-3) – 2 images
• Planet – 270 unique scenes, ~84,000 km2
• Plans:• Getting data for Ukraine and Tanzania
• No issues or challenges in downloading the data
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WV-3, 21 July 2018,1.2 m, Red-Green-Blue
© 2018, DigitalGlobe; NextView License
Planet, 30 August 2018, 3 m, Red-Green-Blue
Preliminary results• Calibration
• Issues with Planet
• Geo-referencing
• Planet: Good (visually) co-registration
• WV-3: Delivered as Level-1B –
without ortho-rectification
• Ortho-rectification with 30 m SRTM DEM (using
GDAL routines): Still ~10 px registration error
• Manual GCPs selection to enable subpixel
accuracy (RMSE<1px)
• Atmospheric correction
• LaSRC – adaptation from Landsat 8 and
Sentinel-2 (Vermote et al. 2016)
20180515_163100_101c_3B_AnalyticMS_TOA20180515_163059_101c_3B_AnalyticMS_TOA
20180515_163111_100e_3B_AnalyticMS_TOA
Planet, True color TOAR: 0.09-0.14G: 0.1-0.15B: 0.12-0.16 4
Preliminary results
Yield, bu/ac
20 8050
SoybeanYield, bu/ac
90 270180
Corn Field scale yield:
186 ± 24 bu/ac (13%)
(11.7 t/ha)
Field scale yield:
52 ± 9 bu/ac (16%)
(3.5 t/ha)
5720 m 720 m
Field scale yields for
corn and soybean
(Hamilton County, IA,
USA). Provided by Iowa
State University
Preliminary results: WV-3NDVI, R2=0.119
CIgreen = NIR/Green-1,R2=0.371DVI = NIR-Red, R2=0.147
WV-3Corn
21 July 2018, DOY=202
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0
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3.green 4.yellow 5.red 6.red-edge 7.nir1
Rel
ativ
e im
po
rtn
ace,
%
Sprectral bands
Relative importance(corn, WV-3 2018-202, 5 bands
R2=0.477)
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5
10
15
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45
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3.green 5.red 6.red-edge 7.nir1
Rel
ativ
e im
po
rtn
ace,
%
Sprectral bands
Relative importance(corn, WV-3 2018-202, 4 bands
R2=0.476)
0
5
10
15
20
25
30
35
40
45
50
3.green 6.red-edge 7.nir1
Rel
ativ
e im
po
rtn
ace,
%
Sprectral bands
Relative importance(corn, WV-3 2018-202, 3 bands
R2=0.476)
Preliminary results: Planet Planet, soybean, R2 over time
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0.1
0.2
0.3
0.4
0.5
0.6
0.7
2018160 2018180 2018200 2018220 2018240 2018260 2018280 2018300 2018320
Rsq
Year and DOY
Planet, soybean
0
10
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30
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60
70
blue green red NIR
Rel
ativ
e im
po
rtan
ce, %
PlanetLab spectral bands
Relative importance
Yield (from machinery)
Yield (from satellite, 3m)
Yield, bu/ac
20 8050
Maximum R2=0.59
for DOY=242 (30 August)
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Conclusions & Next Steps
• Calibration issues on Planet
• Green/Yellow, Red Edge and NIR: most important explaining
corn/soybean yield variability
• High temporal frequency of Planet allows identification of best suitable
date for yield assessment
• Next steps• Planet co-registration analysis (Skakun et al. 2017 IJDE)
• Expanding crop yield mapping for multiple fields
• Crop type mapping with Planet (small fields in Ukraine and Tanzania)8
Acknowledgments
• NASA• “Crop Yield Assessment and Mapping by a Combined Use of Landsat-8,
Sentinel-2 and Sentinel-1 Images” (#80NSSC18K0336)
• Digital Globe• "DigitalGlobe data were provided by NASA's Commercial Archive Data for
NASA investigators (cad4nasa.gsfc.nasa.gov) under the National Geospatial-Intelligence Agency's NextView license agreement."
• Planet• Planet Team (2017). Planet Application Program Interface: In Space for Life
on Earth. San Francisco, CA. https://api.planet.com
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