Hydrologic Dynamics of the Ground-Water-Dependent Sian Ka’an Wetlands, Mexico, Derived from InSAR and SAR Data

Authors

Bibi R.N. Gondwe, Technical University of Denmark Department of Environmental Engineering
Sang-Hoon Hong, University of Miami Division of Marine Geology and GeophysicsFollow
Shimon Wdowinski, University of Miami Division of Marine Geology and GeophysicsFollow
Peter Bauer-Gottwein, Technical University of Denmark Department of Environmental Engineering

Abstract

The 5,280 km² Sian Ka’an Biosphere Reserve includes pristine wetlands fed by ground water from the karst aquifer of the Yucatan Peninsula, Mexico. The inflow through underground karst structures is hard to observe making it difficult to understand, quantify, and predict the wetland dynamics. Remotely sensed Synthetic Aperture Radar (SAR) amplitude and phase observations offer new opportunities to obtain information on hydrologic dynamics useful for wetland management. Backscatter amplitude of SAR data can be used to map flooding extent. Interferometric processing of the backscattered SAR phase data (InSAR) produces temporal phase-changes that can be related to relative water level changes in vegetated wetlands. We used 56 RADARSAT-1 SAR acquisitions to calculate 38 interferograms and 13 flooding maps with 24 day and 48 day time intervals covering July 2006 to March 2008. Flooding extent varied between 1,067 km² and 2,588 km² during the study period, and main water input was seen to take place in sloughs during October–December. We propose that main water input areas are associated with water-filled faults that transport ground water from the catchment to the wetlands. InSAR and Landsat data revealed local-scale water divides and surface water flow directions within the wetlands.

Comments

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Recommended Citation

Gondwe, B.R.N., S.-H. Hong, S. Wdowinski, P. Bauer-Gottwein. 2010. Hydrodynamics of the groundwater-dependent Sian-Ka'an wetlands, Mexico, from InSAR and SAR data. Wetlands 30(1): 1-13.