Airborne LiDAR for forest mapping

Airborne LiDAR for forest mapping

Poate Degei1, Fabian Enßle², Wolf Forstreuter1 Barbara Koch²1SPC/SOPAC GIS/RS

²Department of Remote Sensing and Landscape Information Systems - FeLIS

[email protected]

21.04.23

27.11.2012 – 30.11.2012 PACIFIC GIS/RS USER CONFERENCE 2

• Introduction to Airborne Laser Scanning (ALS)

• ALS data recorded at Nadi

• Various capabilities of LiDAR data

• TreesVIS software

• Summary & Conclusion

Outline

21.04.23


• ALS is an active remote sensing technique

• Laser scanner can be mounted on airplanes,

helicopters or UAV’s

• Laser scanner technology has several advantages

• 3D mapping of vegetation

• Laser penetrates thru canopy

• Principals and data will be described in next slides

Airborne Laserscanning (ALS)

Source: http://www.riegl.com

21.04.23 27.11.2012 – 30.11.2012 PACIFIC GIS/RS USER CONFERENCE 4

Easting Northing Elevation Intensity 3462486.09 5483534.20 93.74 32 3462484.77 5483533.61 93.97 35 3462483.42 5483533.01 93.50 74 3462482.08 5483532.41 93.50 25 3462480.75 5483531.82 93.48 55 3462479.44 5483531.23 93.87 94 3462478.12 5483530.64 94.02 107 3462477.01 5483530.14 97.74 28 3462475.51 5483529.47 94.89 58 3462474.22 5483528.89 95.49 78 3462472.91 5483528.30 95.78 32 3462471.57 5483527.71 95.77 25 3462470.43 5483527.19 98.49 18 3462468.92 5483526.52 95.90 41

LILLESAND ET AL. 2008

TSOULIS 2006

C. Brenner ISPRS Summer school 2006




21.04.23


First ALS data recorded in Viti Levu

ALS data flight in Nadi area

• A subset is used in next slides

• Financed by World Bank

• May, 2012

• Island Hoppers helicopter

• Light Detection & Ranging

equipment

Demonstration area


Bird view

A B

Look from Mark B towards A


Cross section between mark A and mark B (depth 5m)



Calculation of Digital Terrain Models (DTM)



Calculation of Digital Surface Models (DSM)



normalized DSM (nDSM)

• Height of objects

• Vegetation

• Buildings



Inclination (surface slope) calculation

• Precise DTM‘s important

• Accessibility to forests

• Environmental modeling

• Soil erosion

• Water drainage

12

Assessment of multilayer structure within the vegetation

Wang et al. 2007 FeLis Double layer forest stand

Single layer forest stand with trees of mixed height

09.11.2010 27.11.2012 – 30.11.2012 PACIFIC GIS/RS USER CONFERENCE


21.04.23 13

Assessment of canopy closure and height


27.11.2012 – 30.11.2012 PACIFIC GIS/RS USER CONFERENCE

Example from a German forest (by Christoph Straub)

• Forest segmentation

• By height

• Canopy closure

• Species composition

14

3D real-time visualisation

Calculation of DSM, DTM, nDSM

True orthophoto calculation

Processing and filtering of raw data

Modules for object extraction

Combining TLS and ALS data

Laser flight simulation

TreesVIS – Software skills

09.11.2010

• Data processed with TreesVIS

• Developed at Dep. of Remote

Sensing; University Freiburg

• Special prices for research and

students

27.11.2012 – 30.11.2012 PACIFIC GIS/RS USER CONFERENCE


Summary & Conclusion

Various capabilities of LiDAR technology

• 3D point information

• Precise Digital Surface Models

• Precise Digital Terrain Models even under forest canopy

• Data is useful for multiple purposes

• Forest mapping

• Environmental and Disaster modeling/mapping

• Urban area mapping (houses, transmission lines)

• Data acquisition is expensive, but of high value due to its use

for multiple purposes


Thank you for your attention

The authors are greatful to:

The ReCover consortium within the FP7 programme (no. 263075)

http://www.vtt.fi/sites/recover/?lang=en

Vinaka Vakalevu

Airborne LiDAR for forest mapping

Documents

airborne lidar

viti levuals data flight

nadi areaa subset

assessment of canopy

uavslaser scanner technology

fabian enle

forest mappingpoate

world bank