Title :
Biomass assessment in african forest-savanna using ALOS PALSAR data
Author :
Mermoz, Stephane ; Le Toan, Thuy ; Villard, Ludovic ; Lasne, Yannick
Author_Institution :
CESBIO, Univ. of Paul Sabatier, Toulouse, France
Abstract :
The purpose of this work is to assess biomass in forest savanna and to analyse changes in biomass from 2007 to 2010 in Cameroon, by using ALOS PALSAR data. The methodology includes an inter-calibration step, and multi-image filtering for noise reduction and preservation of the resolution. An existing direct model previously developed by CESBIO over various forests, linking γhvo to biomass, is inversed using a probabilistic bayesian approach. There is a mean of 52 t.ha-1 of biomass in 12 553 km2 which represents 32.63 Mt of carbon not taken into account in existing carbon budget assessments. Besides, forest savanna transition and changes in AGB from 2007 to 2010 are analysed. Changes are mainly due to shifting cultivation, grazing fires, degradation and deforestation.
Keywords :
Bayes methods; atmospheric composition; calibration; carbon; geophysical image processing; image denoising; vegetation mapping; ALOS PALSAR data; African forest-savanna; CESBIO; Cameroon; biomass assessment; carbon budget assessments; deforestation; forest savanna transition; grazing fires; intercalibration step; multiimage filtering; noise reduction; probabilistic bayesian approach; shifting cultivation; Bayesian methods; Biomass; Carbon; Degradation; Estimation; L-band; Standards; Savanna forest; biomass retrieval; multitemporal analysis;
Conference_Titel :
Geoscience and Remote Sensing Symposium (IGARSS), 2012 IEEE International
Conference_Location :
Munich
Print_ISBN :
978-1-4673-1160-1
Electronic_ISBN :
2153-6996
DOI :
10.1109/IGARSS.2012.6352723