Synoptic analysis of surface structures in tropical coastal wetlands: a case study in Amazonia, North Brazil

LARA, RUBÉN JOSÉ; COHEN, MARCELO; SZLAFSZTEIN, C.F.

San José, Costa Rica

Congreso; COLACMAR X Congreso Latinoamericano de Ciencias del Mar; 2003

Universidad Nacional de Costa Rica

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:72.0pt 90.0pt 72.0pt 90.0pt; mso-header-margin:35.4pt; mso-footer-margin:35.4pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> An integrated multidisciplinary approach developed during a long-term project on coastal wetlands in North Brazil has allowed the recognition of driving forces shaping the structure of the mangrove ecosystem in that macrotidal region. Small differences in topography are sensitively reflected in flooding regime and biogeochemical and geobotanical features of the present system. An empirical model based on inundation dynamics was developed which provided a realistic appraisal of the synoptic distribution of porewater salinity in the Bragança Peninsula. Time series analysis of satellite images revealed significant changes in the wetlands in the last 25 years, reflected by net losses of vegetation coverage, mangrove invasion into salt marshes and a highly changing coastal morphology. This seems to be induced by changes in relative sea-level and/or coastal circulation patterns. Some socio-economic implications of this change are discussed.