Remote Sensing of Wetland Types: Subtropical Wetlands of Southern Hemisphere

Abstract

The Pantanal of South America , located in the center of South America, between Brazil, Bolivia, and Paraguay, represents one of the largest wetlands in the southern hemisphere subtropics. Estimates suggest that the inundated area of the Pantanal covers approximately 160,000 km² during maximum flooding, and with the entire Pantanal watershed occupying an area of approximately 362,000 km² (Junk et al. 2006). The upper Paraguay River and its three tributaries feed the Pantanal wetlands, promoting a strong annual unimodal flood that varies in duration, amplitude, and extent both yearly and spatially (Hamilton et al. 1996). Such characteristic flood dynamics require morphological, anatomical, physiological, and/or ethological adaptations from the local biota. As these seasonal water level variations are the driving force of ecological processes in floodplain systems, identifying the various permanent and semipermanent terrestrial and aquatic habitats in a seasonal flood-pulse ecosystem is critical for understanding the biogeochemical, hydrological, and ecological processes of the ecosystem (Hamilton et al. 1996). The dynamics of inundation in the Pantanal also promote a high diversity of vegetation (Alho 2008), expressed by a unique landscape characterized by different compositions of savanna vegetation, abundant species of aquatic vegetation, and different types of floodplain forests (Alho 2008). In addition to the floristic diversity, a large number of hydrochemically varied lakes, waterways, and other fluvial geomorphological patterns are observed, generating a complex mosaic of wetland habitats (Por 1995; Costa and Telmer 2006; Evans and Costa 2013; Evans et al. (2014).