The morphodynamic aspects related to erosion or accretion of the coastline are some of the
topics analyzed in the management of coastal zones being discussed around the world in order
to monitor and protect these zones. This thesis aims to analyze the behavior of the coastal
morphodynamics of the Salinópolis, relating to the use of ocean margin. The study area was
compartmentalized into three sectors: Western (Corvina and Maçarico beaches), Center (Farol
Velho beach) and Eastern (Atalaia beach). The methodology consisted of: (a) acquisition and
processing of multi-temporal images (1988-2001-2013) of the Landsat 5 TM, 7 ETM and 8
OLI; (b) application of interviews/questionnaires with bathers, (c) acquisition of field data
during the rainy season (April 26th, 27th and 28th, 2013) and less rainy (04<th, 05th and 06th,
2013) ; and (d) laboratory analysis for processing the data acquired in the field (beaches
topography, sampling of surface sediments of the same and with the use of traps, and
oceanographic measurements of waves, tides, currents and turbidity). In Laboratory were
made graphics of topographic profiles of beaches, calculated granulometric statistical
parameters of Folk & Ward (1957), the rates of sediment transport on beaches and
morphometric parameters of Short & Hesp (1982), the latter were calculated in order to relate
them to the morphodynamic states of beaches proposed by Wright & Short (1984) and
Masselink & Short (1993). For the classification of the oceanic coast of the Salinópolis in
terms of use and occupation was used decree n° 5.300/2004. From the research about
urbanization on the coast and works located in coastal environments was used a matrix
proposed by Farinaccio & Tessler (2010) which lists a number of environmental impacts, and
the geoindicators table of behavior of the coastline proposed by Bush et al. (1999), to identify
places with vulnerability to erosion or accretion. For the oceanographic conditions at each
beach and dangerous to bath in them were integrated the data of waves, currents, beach
morphodynamics and questionnaires applied with bathers. Currently, the oceanic coast of
Salinópolis has different characteristics regarding the use and conservation, ranging from the
type of natural coast (Class A) until coast with consolidated urbanization (Class C). The first
occurs at the extremes of the study area and the second in the district area. Four types of
beaches were identified according to maritime exposure and the degree of oceanographic
conditions: type 1 (Maçarico), type 2 (Corvina), type 3 (Farol Velho) and type 4 (Atalaia).
The part of coast with major environmental impacts and high coastal erosion is located on the
Farol Velho beach. The degree of danger to the bath was 4 (Macarico beach) to 7 (Atalaia
beach) - medium to high degree of risk. The Salinópolis beaches have gentle slopes (<1.5°),
large variations in the coastline between seasons of the year (9.6 to 88 4 m) and variable
sediment volume depending on the degree of exposure to the open ocean. Dissipative
morphodynamic state (Ω>5.5) prevailed at these beaches, but with the occurrence of the the
longshore bar and trough state (4.7 <Ω <5.5) in the western sector. The macrotidals in the
study area showed maximum height of 5.3 m (Center Sector during the less rainy season) and
a minimum of 4 m in the same sector during the rainy season. The longshore currents were
more intense in the eastern sector (> 0.45 m / s) during the two seasons of the year. The wave
heights were also higher in the eastern sector (maximum of 1.05 m during the flood tide in the
less rainy season) and wave periods were shorter (<4.5 s) in the western sector. The mean
grain size obtained from sediments collected on the beaches had more frequent scale between
2.6 to 2.8 phi, indicating the predominance of fine sand. The predominant degree of sorting of
sediment was 0,2 to 0,5 phi (very well sorted and well sorted), and asymmetry was positive
(0.10 to 0.30) and nearly symmetrical (-0.10 to 0.10). The degree of kurtosis ranged from very
platykurtic (<0.67) to very leptokurtic (1.50 to 3.00). Sediment accretion events were
observed of the rainy season to less rainy season. From 07/22/1988 to 08/28/2013 (25 years)
also predominated accretion, where the average linear advancement of the coastline was
190.26 m. The average linear retreat obtained for the entire study area was -42.25 m. The
eroding areas are point: currencies from the beaches of Corvina and Maçarico, and Farol
Velho and Atalaia. Portable traps indicated a greater quantity of sediment transported
longitudinally in the less rainy season (minimum 280 g/m3: flood, west sector; maximum
1098 g/m3: ebb, east sector). In the traps applied in the swash zone, the balance of sediment
entering and leaving the beaches was lower in the center sector (minimum 80 g/m3: ebb,
maximum 690 g/m3: flood; less rainy season). The coastal sediment movement is derived
mainly from effect of the tides, which are oriented toward the direction of the ebb and flow of
the estuary crossing the coast. The data indicate the longshore transport of sediment from the
Atalaia island and Sampaio River to the west sector and the beaches margins.
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