Skip to main content
ARS Home » Research » Publications at this Location » Publication #192807
Title: ASSESSMENT OF C-BAND SYNTHETIC APERTURE RADAR DATA FOR MAPPING COASTAL PLAIN FORESTED WETLANDS IN THE MID-ATLANTIC REGION, USA

Author
item Lang, Megan
item PITTMAN, K - UNIVERSITY OF MARYLAND
item KASISCHKE, E - UNIVERSITY OF MARYLAND
item PRINCE, S - SOUTH DAKOTA STATE UNIV

Submitted to: Remote Sensing of Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/31/2007
Publication Date: 8/9/2008
Citation: Lang, M.W., Pittman, K.W., Kasischke, E.S., Prince, S.D. 2008. Assessment of C-band synthetic aperture radar data for mapping Coastal Plain Forested Wetlands in the Mid-Atlantic Region. Remote Sensing of Environment. 112:4120-4135.

Interpretive Summary: Assessment and management of wetlands requires accurate and easily updated maps at a regional scale, yet with a fine enough resolution to be able to detect smaller wetlands. Wetlands are often mapped using visual interpretation of aerial photography, however the need for consistent, regional maps that also facilitate the monitoring of landscape alteration make this conventional approach impractical for larger areas. Forested wetlands are very extensive in the U.S. Mid-Atlantic Coastal Plain, but these cannot readily be distinguished from forested uplands using short wavelength (visible and near infrared) satellite-based remote sensing. Synthetic aperture radar (SAR) images have been shown to be able to detect flooding and relatively large variations in soil moisture below temperate, deciduous tree canopies and therefore may be able to improve current forested wetland maps. In this study we compare multi-temporal C-band (5.6 cm wavelength) SAR data, collected by ERS-1/2 and ENVISAT satellite systems, with field observations of inundation and U.S. Fish and Wildlife Service National Wetland Inventory maps in a large forested wetland in Laurel, MD, USA. Multi-temporal C-band SAR data were shown to be capable of mapping forested wetlands at the study site and the discrimination of wetland from upland was improved with digital elevation data. The results are encouraging and justify the application of SAR data to the entire Mid-Atlantic Coastal Plain as a step towards benchmarking the technique for routine mapping.

Technical Abstract: Assessment and management of wetlands requires accurate and easily updated maps at a regional scale, yet with a fine enough resolution to be able to detect smaller wetlands. Wetlands are often mapped using visual interpretation of aerial photography, however the need for consistent, regional maps that also facilitate change detection make this conventional approach impractical for larger areas. Forested wetlands are very extensive in the U.S. Mid-Atlantic Coastal Plain, but these cannot readily be distinguished from forested uplands using short wavelength (visible and near infrared) satellite remote sensing. Synthetic aperture radar (SAR) images have been shown to be able to detect flooding and relatively large variations in soil moisture below temperate, deciduous tree canopies and therefore may be able to improve current forested wetland maps. In this study we compare multi-temporal C-band SAR data, collected by ERS-1/2 and ENVISAT satellite systems, with field observations of inundation and U.S. Fish and Wildlife Service National Wetland Inventory maps in a large forested wetland in Laurel, MD, USA. Multi-temporal C-band SAR data were shown to be capable of mapping forested wetlands at the study site and the discrimination of wetland from upland was improved with digital elevation data. The forested wetland maps, created with SAR data, agreed best (~96-63% agreement) with the areas that were flooded for the longest period of time (25%) and least (~89-44% agreement) with areas flooded for the shortest period of time (5%). The results are encouraging and justify the application of SAR data to the entire Mid-Atlantic Coastal Plain as a step towards benchmarking the technique for routine mapping.