Mapping of African
Tulip
with WorldView-2
Image Data
Litia Gaunavou
Wolf Forstreuter
African tulip
Spathodea campanulata
History and Problem
• Imported as ornamental tree
• Grows in abandoned farms
• Grows in forest openings
• Competition to local species
• Very light wood not usable ?
• Not mapped in Fiji
Mapping Purpose
1. Indicator for forest degradation
2. Eltech Fiji Limited utilises the
timber for energy production
Flowering Season
August - November
African Tulip Grows in Groups
Mapping scale 1:10,000 required
Natural Colour
Bands: 5,3,2 Enhanced
Absorption and Reflection of
Leaves
1 green light
2 blue light and
red light
3 near infrared
Bands: 7,5,3 Enhanced
Infra - Red
Image Capture
• July - November too short to get
cloud free images
• Spectral signature of leave
reflection must be investigated
WorldView-2 Image
Normal view (Google Earth)
Landsat Image Data
WorldView-2 Image
Natural colour combination enhanced
WoldView-2 Image
False colour IR combination,
African tulip is visible
Target: Spectral Signatures
-200
0
200
400
600
800
1000
1200
1400
1 2 3 4 5 6 7 8
W
a
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WorldView 2 Bands
AfricanTulip
Forest
Spectral Signatures African Tulip & other Forest
WorldView-2 Bands
Re
fle
cta
nc
e
Classification of Test Areas
Data AfricanTul AfricanTul Forest1 Forest2 Forest3
AfricanTul 100.00 3.57 0.39 0.48 0.34
AfricanTul 0.00 85.71 1.52 1.83 2.90
Forest1 0.00 0.00 57.92 18.42 13.21
Forest2 0.00 7.14 23.60 60.91 17.73
Forest3 0.00 3.57 16.57 18.36 65.81
Summary
• Mapping of African tulip is
possible also outside the
flowering season
• Mapping requires image data for
1:10,000 scale
• Mapping requires image
enhancement not possible with
Google Earth screen dumps!
Thanks …