Estuaries are transitional places between the continent and the oceans, where the river meets
the sea, resulting in dilution of seawater. In this environment, is established the development of
a typical tropical vegetation known as mangroves. This ecosystem is a good indication in
relation to coastal changes, which can be used as a parameter to assess changes in sea level,
since the coastline is under processes of accretion and erosion. The coastal changes resulting
from these processes are detected by satellite data in time series in different time scales,
making a mangrove excellent bio-indicator for the detection of coastal changes. The images
used in this work was digitally processed Landsat TM-5 of the years 1984 and 2008.
Processing techniques included atmospheric correction, orthorectification, calibration,
segmentation and classification of object-oriented. As results were mapped classes as water
mass, exposed soil, upland coastal plain, sand bars and mangroves. The series found that there
was an increase of 10% of the mangrove vegetation continentalward, due to stronger salinity
near the coast and with one of the reasons for the rise of sea level that may result from climate
change or ( neo) tectonic global.
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