Table 4.

A summary of studies using SAR remote-sensing and Altimetry for the characterization of wetland types in the Amazon region.

RADAR Technology	Sensor	Main Results	Product	Reference
Airborne SAR		Classification of vegetation and wetlands	Periodic wetland maps	[74]
C- and L-band SAR	SIR-C	Discrimination between flooded and non-flooded forest in the Amazon	Extent of flooded forest in the Amazon basin	[49]
L-band SAR	JERS-1	Mapping of forest wetlands using L-band SAR	Maps of wetland extent in the central Amazon region	[39]
C- and L-band SAR	ALOS PALSAR + RADARSAT-2	Usefulness of the C-band for the characterization of herbaceous wetlands and improvement of classification accuracy by combining C- and L-bands	Pixel-based classification of wetlands	[58]
SAR interferometry + altimetry	JERS-1 + TOPEX/POSEIDON	Detection of centimeter scale variations of the water surface height in lake Balbina		[67]
L-band SAR	JERS-1	Backscatter values and radar texture for floodplain forest, mangrove forest, flooded forests, dense canopy forest	Regional vegetation and wetland maps	[75]
C-band SAR	RADARSAT-1	Backscatter values and radar texture for classification of various types of mangroves	Mangrove mapping	[76]
L-band SAR	ALOS-PALSAR	Classification of flooded vegetation using the segmentation of a multi-temporal, dual polarization image stack and temporal backscattering signatures	Classification of wetland habitats	[39]
Altimetry	ENVISAT	Time and space variations in water stored in or circulating through rivers, floodplains, wetlands and lakes in the major sub-basins of the Amazon basin	Water storage and circulation in the Amazon basin	[77]
C- and L-band SAR	ALOS PALSAR + RADARSAT-2	Map ecosystems and create a 3-level lake distribution map of the Lower Nhecolàndia subregion in the Brazilian Pantanal	First line spatial resolution classification showing the spatial distribution of terrestrial and aquatic habitats for the entire subregion of Lower Nhecolàndia	[78]
L-band SAR	ALOS-PALSAR	Quad-polarization performs better for forest classification and classification accuracy improves when SAR and optical imagery are combined	Forest classification in the Amazon	[79]
L-band SAR	ALOS-PALSAR	Classification if the state of inundation of the entire Amazon using ScanSAR mode	Inundation maps of the Amazon basin	[80]
L-band SAR	ALOS-PALSAR	Classification of wetland areas into five land-cover classes using dual-season backscattering values	Extent of flooded areas in the Amazon basin during low and high water seasons	[81]