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The Potential for Integration of Lidar into FIA Operations. Joseph E. Means Forest Science Department Oregon State University Kenneth C. Winterberger PNW Research Station. Talk Outline. Introduction to airborne scanning lidar Capital Forest Lidar Study Other uses of lidar in forestry - PowerPoint PPT Presentation
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The Potential for Integration of Lidar into FIA Operations
Joseph E. MeansForest Science Department
Oregon State UniversityKenneth C. Winterberger
PNW Research Station
Talk Outline
Introduction to airborne scanning lidarCapital Forest Lidar StudyOther uses of lidar in forestryA plan for integrating lidar into FIA estimation procedures
Airplane cartoon
Transect 700m Wide
Transect Closer
Footprint Pattern
Footprints Close-up
Point Cloud
Apparent in Point Clouds
TopographyVegetation heightCanopy depthUnderstory or lackIndividual crowns
Multiple Return TechnologyMultiple Return Technology
Dave Harding, Goddard Space Flight Center, Maryland
Capital Forest Lidar Study
Joseph E. Means, Forest Science, OSUKen Winterberger, PNW, Anchorage, AKDavid Marshall, PNW, Olympia, WAHans Andersen, Coll. For., Univ. Wash.
Capital Forest Lidar Study
South of Olympia, Site Class 1 & 2 Douglas-fir
At Blue Ridge Site of Silvicultural Options Study
Lidar research cooperatively supported by FIA $38,000, RSAC $10,000, OSU $45,000Lidar Data flown by Aerotec, courtesy of Steve Reutebuch, PNW SeattlePlot data from Dave Marshall, PNW, Olympia (92), Ken Winterberger (9), Hans Andersen, UW (6)
Orthophoto Overview
Goals for Plot EstimatesDevelop the capability to estimate plot features using lidar data:
HeightCanopy coverBasal areaCubic volumeTree biomass
Additional equations were developed for:
Stocking densityStand Density Index
Goals for Mean Tree Estimates
Develop the capability to predict means & standard errors:
Height & Lorey heightDBH & Quadratic mean DBHBasal areaVolumeBiomass
Aerotec DEM & DTM Problems
Canopy DEM had too-low elevationsDTM elevations were above many lidar last returns
Aerotec Canopy DEM Hole
New Capital Forest Canopy DEM – No Hole
Aerotec ground DTM too high
Comparison of DTMs: 1st return errors
Average number of negative heights (% in parens)
Average height discrepancy(cm)
Maximum height discrepancy(cm)
New DTM 118 (5%) -8 -20
Aerotec 1999 DTM 388 (17%) -18 -70
New Capital Forest Canopy DEM
New Capital Forest Ground DTM
3_D Capital Forest
Bare Ground/Canopy
Vegetation Height, Capital Forest
Canopy Cover @ 1 m Height
Goals for Plot EstimatesDevelop the capability to estimate plot features using lidar data:
HeightCanopy coverBasal areaCubic volumeTree biomass
Additional equations were developed for:
Stocking densityStand Density Index
Lorey Height
Volume
Tree Biomass
Stocking Density
Stand Density Index
Goals for Mean Tree Estimates
Develop the capability to predict means & standard errors:
Height & Lorey height (same as plot averages)DBH & Quadratic mean DBHBasal areaVolumeBiomass
Height Std. Dev.
Diameter (quadratic mean)
Diameter (Quadratic mean) Std. Dev.
HJ Andrews Lidar Paper – ERDAS Award
ERDAS Award for Best Scientific Paper in Remote Sensing 3rd Place, 2001
American Society of Photogrammetry & Remote Sensing
Means, J.E., S.A. Acker, B.J. Fitt, M. Renslow, L. Emerson, and C. Hendrix. 2000. Predicting forest stand characteristics with airborne scanning lidar. Photogrammetric Engineering & Remote Sensing 66(11):1367-1371.
Additions to FIA Presentation
LHP-FHP-Tree Characteristics Links
LHP (Laser Height Profile)
FHP (Foliage Height Profile)
Tree & Plot Characteristics
Lidar measures &Multiple regression
Not mechanisticLimited applicabilityRisk of over-fitting
How mult regression with many potential predictors
works
Height percentiles are cumulative upwardsCover percentiles are cumulative downwards
LHP Ht%ile Cov%ile
Mult Regress pulls info out of LHP
LHP -> Tree & Plot CharacteristicsCan be described quantitatively by multiple regression
Interaction of predictors and coefficients (+/-) allows “best” transformation of LHP to be used
LHP-CHP-Tree Characteristics Links
LHP FHP
Tree & Plot Characteristics
Beers Law k=1
Statistical link functionMagnussen, et al 1999height only, distribution
Few places with foliageheight profiles
Lidar measures &Multiple regression
Not mechanisticLimited applicabilityRisk of over-fitting
Moment armMechanistic modelGives bole taperIndividual tree
Understanding relationships between
LHP <-> tree characteristic
We can describe quantitatively:LHP -> Mean height for Douglas-fir in B.C. Applicable to other monocultures. Magnussen, et al. 1999
We cannot describe quantitatively:LHP -> FHPIs possible in very few places where have measured vertical distribution of foliage
Understanding relationships between
LHP -> tree characteristicLHP -> FHP
Cannot describe quantitatively or mechanistically except at a very few places where know vertical foliage distribution
LHP -> Tree & plot characteristics (DBH, BA, volume, biomass, TPH, SDI)
Cannot describe mechanistically except for individual trees with complete foliage distribution using moment arm model. Potential to expand to all spp.
Long-Range Plan
Mechanistic models estimate FHP and Tree & Plot characteristicsWhen needed, estimate species groups with limited ground plot data and multi-temporal ETM+
LHP-CHP-Tree Characteristics Links
LHP FHP
Tree & Plot Characteristics
Statistical link functionMagnussen, et al 1999height only, distribution
Use foliage height profiles to estimate FHP with extinction
coefficient that varies with depth
Lidar measures &Multiple regression
Not mechanisticLimited applicabilityRisk of over-fitting
Moment armMechanistic modelGives bole taperIndividual tree
By species groupdistribution of crown shapes
Lidar Uses: Stand StructureAccurate inventories at the stand level:
HeightDBHVolumeSite index, with knowledge of stand ageForm factor *
Parameterize stand growth modelsDiameter distributions, Height distributions ** = Work is needed
Leaf Area (r2 = .8 to .9)
Cougar Reservoir StandsYoung Stand Thinning and Diversity
Study
Cougar Reservoir StandsYoung Stand Thinning and Diversity Study
Vegetation height [0 – 80 meters]
Cougar Reservoir StandsYoung Stand Thinning and Diversity StudyCover percent at 15 meters above ground
Cougar Reservoir StandsYoung Stand Thinning and Diversity
StudyWood volume [0 – 1000 m3/ha]
More work needed for first draft from here on
Lidar Uses: Streams & WatershedsRiparian forest structure:
Stream shading -> stream temperature modelingInput to models of woody debris input to streams*Inventory in riparian zones
Valley floor topographyChannel width, bank incision*, stream gradient, terraces, fans, side channels
Fine-scale watershed structureDepth of road prism cuts, headwall basin size-gradient-locations, small gullies*Input to models of soil and regolith depth, modeling of watershed hydrology, canopy water retention & buffering*
* = Research is needed
Aerial PhotographAerial Photograph
SBG NW FORETRY PROJECT - FLOWN JULY, 1996 - 1:32 000 SCALE
TIN of First SurfaceTIN of First Surface
TIN of Understory & Bare TIN of Understory & Bare EarthEarth
3-D Fuels Mapping
Live fuels mappingCanopy heightCanopy depth *Understory vegetation height, cover *Vertical distribution of ladder fuels *Turn around in a few hours *Distinguish species, live vs. dead when integrate with multi-spectral data* = Work is needed to develop system
Weyerhaeuser Springfield Tree Farm Lidar Study
DTM [650-1010 m elevation]
Weyerhaeuser Springfield Tree Farm Lidar Study
Vegetation height [0 - 40 meters]
Weyerhaeuser Springfield Tree FarmLidar Study, South Site
Weyco Lidar Study, South Site
Wildlife Habitat Applications
Vegetation cover, height, tree size, density at different levels above ground, canopy depthUnderstory plant composition based on
Stand structure, light environment, topographyDistance from water, roads
For gaps and patches of dense vegetationSizes, shapes, height above ground, connectedness, location
The View Inside: Transects
Show vertical canopy profiles
Show understory gaps in canopy & fuels
A Progressive Study:Can Lidar be Profitably Used by
FIA? Winter & Spring:
Slope correctionPublish slope & Capital Forest papersIf slope correction successful then plan for lidar flight in summerStand-level estimates and SE’s
Summer: lidar flight to start study to answer questions:
Species groups & species separations:Conifer & broadleaved separation using intensity of 1st returnsUnderstory tree characteristics from canopy height profile
Statistics of lidar-based stand-level & sub-regional level estimatesDiam, ht & vol distributions
Cougar Reservoir Stands,Transect Locations
Cougar Res. StandsTransect Northwest, N-S
Cougar Res. StandsTransect Northeast, N-S
Cougar Res. StandsTransect Southeast, E-W
The View Inside: Layers
Show relative density of canopy layers
Cougar Res. StandsTransect Southeast, N-S
Cougar Res. StandsLayer 0-10 m
Cougar Res. StandsLayer 10-20 m
Cougar Res. StandsLayer 20-30 m