Reviewing ALOS PALSAR Backscatter Observations for Stem Volume Retrieval in Swedish Forest
Artikel i vetenskaplig tidskrift, 2015

Between 2006 and 2011, the Advanced Land Observing Satellite (ALOS) Phased Array L-type Synthetic Aperture Radar (PALSAR) instrument acquired multi-temporal datasets under several environmental conditions and multiple configurations of look angle and polarization. The extensive archive of SAR backscatter observations over the forest test sites of Krycklan (boreal) and Remningstorp (hemi-boreal), Sweden, was used to assess the retrieval of stem volume at stand level. The retrieval was based on the inversion of a simple Water Cloud Model with gaps; single estimates of stem volume are then combined to obtain the final multi-temporal estimate. The model matched the relationship between the SAR backscatter and the stem volume under all configurations. The retrieval relative Root Mean Square Error (RMSE) differed depending upon environmental conditions, polarization and look angle. Stem volume was best retrieved in Krycklan using only HV-polarized data acquired under unfrozen conditions with a look angle of 34.3° (relative RMSE: 44.0%). In Remningstorp, the smallest error was obtained using only HH-polarized data acquired under predominantly frozen conditions with a look angle of 34.3° (relative RMSE: 35.1%). The relative RMSE was below 30% for stands >20 ha, suggesting high accuracy of ALOS PALSAR estimates of stem volumes aggregated at moderate resolution.

forest

Sweden

stem volume

backscatter

ALOS PALSAR

boreal

retrieval

Författare

Maurizio Santoro

Gamma Remote Sensing AG

Leif Eriksson

Chalmers, Rymd- och geovetenskap, Radarfjärranalys

J. E. S. Fransson

Sveriges lantbruksuniversitet (SLU)

Remote Sensing

2072-4292 (ISSN)

Vol. 7 4 4290-4317

Drivkrafter

Hållbar utveckling

Ämneskategorier

Fjärranalysteknik

Skogsvetenskap

Fundament

Grundläggande vetenskaper

DOI

10.3390/rs70404290

Mer information

Senast uppdaterat

2018-09-06