FROM AN ESTUARY TO A FRESHWATER LAKE: A PALEO-ESTUARY EVOLUTION IN THE CONTEXT OF HOLOCENE SEA-LEVEL FLUCTUATIONS, SE BRAZIL

Author(s):Show less -

Buso Junior, Antonio Alvaro ^[1] ; Ruiz Pessenda, Luiz Carlos ^[1] ; de Oliveira, Paulo Eduardo ^[2] ; Fonseca Giannini, Paulo Cesar ^[3] ; Lisboa Cohen, Marcelo Cancela ^[4] ; Volkmer-Ribeiro, Cecilia ; Barros de Oliveira, Sonia Maria ^[3] ; Teixeira Favaro, Deborah Ines ; Rossetti, Dilce de Fatima ; Lorente, Flavio Lima ^[1] ; Borotti Filho, Marcos Antonio ^[1] ; Schiavo, Jolimar Antonio ; Bendassolli, Jose Albertino ^[1] ; Franca, Marlon Carlos ; Felix Guimaraes, Jose Tasso ; Siqueira, Geovane Souza

Affiliation

^[1] Ctr Nucl Energy Agr CENA USP, Sao Paulo - Brazil

^[2] Univ Sao Francisco, BR-12900000 Braganca Paulista, SP - Brazil

^[3] Univ Sao Paulo, Inst Geociencias, BR-05508 Sao Paulo - Brazil

^[4] Fed Univ Para, BR-66059 Belem, Para - Brazil

• Document type: Journal article
• Source: RADIOCARBON; v. 55, n. 2-3, p. 1735-1746, 2013.
• Web of Science Citations: 13

Abstract

A sediment core was studied to characterize the influences of Holocene sea-level variations in the Barra Seca River valley, in the Atlantic rainforest, Linhares, Espirito Santo, southeastern Brazil. Biological proxies ( pollen, spores, and sponge spicules), C-14 dating, granulometry, delta C-13, delta N-15, C/N and major chemical elements revealed the establishment and the evolution of a paleo-estuary during the interval from similar to 7700-585 cal BP. During the interval similar to 7700-7000 cal BP, the study site was occupied by a bay-head delta, the inner portion of the paleo-estuary, presenting the most dense mangrove coverage of the entire record. In the interval similar to 7000-3200 cal BP, the site was occupied by the central basin, possibly a consequence of the landward migration of the paleo-estuary. This interval presents reduced mangrove coverage, probably due to the permanent flooding of the valley. From similar to 3200 cal BP, the marine influence at the site decreased probably as result of the seaward migration of the coast line. From similar to 600 cal BP, the modern floodplain and freshwater lake were established. This interpretation is in agreement with the sea-level curves for the southeastern Brazilian coast, except for the fact that evidence of sea levels lower than the present at similar to 4000 and similar to 2500 cal BP as suggested by some authors were not found. (AU)

• FAPESP's process: 07/06222-4 - Holocenic environmental dynamics (vegetation, climate and relative sea-level) based on high resolution interdisciplinary studies, in the northern coast of Espírito Santo state.
• Grantee: Antonio Alvaro Buso Junior
• Support type: Scholarships in Brazil - Master
• FAPESP's process: 07/03615-5 - Reconstruction of vegetation and climate since the middle Holocene in Brazil
• Grantee: Luiz Carlos Ruiz Pessenda
• Support type: Regular Research Grants
• FAPESP's process: 10/18091-4 - Late Quaternary dynamics of Spodosols, vegetation and climate at the northeastern region of Espírito Santo state.
• Grantee: Antonio Alvaro Buso Junior
• Support type: Scholarships in Brazil - Doctorate
• FAPESP's process: 11/00995-7 - Interdisciplinary paleoenvironmental studies in the Espirito Santo State coast
• Grantee: Luiz Carlos Ruiz Pessenda
• Support type: Research Program on Global Climate Change - Thematic Grants