SUMMARY
Remote sensing techniques and fixed-site observations were used to evaluate vegetation, habitat and physiographic characteristics of coastal foredunes in southern Brazil during the last 50 years. The results demonstrated a gradual increase of edaphic stability and biological diversity in foredunes during several decades, followed by a rapid and profound attenuation of these attributes. The changes in regional hydroloy, as a result of long-term and large-scale impoundment and more recent and localized drainage activities, are appointed as the major cause for foredune modifications in this part of the southwestern Atlantic.