Title
Mapping Canopy Height and Growing Stock Volume Using Airborne Lidar, ALOS PALSAR and Landsat ETM+
Abstract
We have investigated for forest plantations in Chile the stand-level retrieval of canopy height (CH) and growing stock volume (GSV) using Airborne Laser Scanner (ALS), ALOS PALSAR and Landsat. In a two-stage up-scaling approach, ensemble regression tree models (randomForest) were used to relate a suite of ALS canopy structure indices to stand-level in situ measurements of CH and GSV for 319 stands. The retrieval of CH and GSV with ALS yielded high accuracies with R(2)s of 0.93 and 0.81, respectively. A second set of randomForest models was developed using multi-temporal ALOS PALSAR intensities and repeat-pass coherences in two polarizations as well as Landsat data as predictor and stand-level ALS based estimates of CH and GSV as response variables. At three test sites, the retrieval of CH and GSV with PALSAR/Landsat reached promising accuracies with R(2)s in the range of 0.7 to 0.85. We show that the combined use of multi-temporal PALSAR intensity, coherence and Landsat yields higher retrieval accuracies than the retrieval with any of the datasets alone. Potential limitations for the large-area application of the fusion approach included (1) the low sensitivity of ALS first/last return data to forest horizontal structure, affecting the retrieval of GSV in less managed types of forest, and (2) the dense ALS sampling required to achieve high retrieval accuracies at larger scale.
Year
DOI
Venue
2012
10.3390/rs4113320
REMOTE SENSING
Keywords
Field
DocType
canopy height,growing stock volume,Chile,ALOS PALSAR,coherence,Landsat,laser scanner,fusion
Laser scanning,Remote sensing,Lidar,Sampling (statistics),Geology,Canopy
Journal
Volume
Issue
Citations 
4
11
11
PageRank 
References 
Authors
0.68
15
4
Name
Order
Citations
PageRank
Oliver Cartus1365.23
j m kellndorfer2252.78
m rombach3110.68
Wayne S. Walker4263.98