Restinga Paralela = Parallel Restinga

(Vicente Mussi-Dias) #1

Árvores de siribeira (Avicennia germinans) mortas pelo avanço do mar na
restinga de Paraíba do Sul


Black mangrove trees (Avicennia germinans) killed by the advance of the sea in
Paraíba do Sul restinga


Therefore, two great extensions of restinga are consti-
tuted. The southern one, between Macaé and Barra do Furado,
from the Pleistocene. Its constitution is due to progradational
beach ridges associated with the regression that occurred af-
ter the transgressive maximum occurred 123,000 years BP. The
coastal elevation of this terrace is low and, after Carapebus la-
goon, the sands of the present beach, of Holocene origin, tres-
pass over the Pleistocene sands. The presence of beach ridges
on the surface of the Pleistocene sandy deposits suggests that
these terraces were not drowned during the last transgression,
suggesting a subsidence process after 5,100 years BP, which
were responsible for their current low altitude. Between the
mouth of the Itapemirim and Guaxindiba rivers, the Pleistocene
sandy deposits reach a remarkable development only in the Ita-
bapoana river valley.

The northern restinga, in turn, formed after the last transgres-
sion, whose maximum was reached in 5,100 years BP and is,
therefore, a very new Holocene restinga when compared with
the southern restinga. The authors return to the goose foot delta
proposed by Lamego and denied by Gilberto Dias. In fact, the
latter is right to contest the former in this respect, since such a
delta would be unfeasible in the open sea. However, this does
not apply to the interior of a semi-open lagoon(40, 43).

The first Symposium about Brazilian Restingas, promot-
ed by the Fluminense Federal University in 1984, was a major
milestone in the studies on restinga geology and ecosystems.
The first systematized and congregated studies on this envi-
ronment were presented at this meeting. Regarding limnology,
a pioneering study was carried out by three researchers in the
restinga lagoons Iodada, Imboacica, Cabiúnas, Comprida, Cara-
pebus, Paulistinha, Paulista and Campelo. In one of the authors'
conclusions,

Regionally, the Fluminense coastal la-
goons are of great importance both from
the point of view of fish production and
crustaceans of high protein and eco-
nomic value and also as leisure areas
for the population. However, most of
these lagoons have undergone profound
changes in their natural conditions.
These changes are mainly caused by the
discharge of domestic and industrial ef-
fluents, by the silting of their banks and
the removal of limestone deposits for in-
dustrial purposes. One of the main con-
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