Banca de DEFESA: JULIANA DE SOUZA SANTANA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : JULIANA DE SOUZA SANTANA
DATA : 30/07/2020
HORA: 14:00
LOCAL: Defesa virtual devido medidas de isolamento socials
TÍTULO:

Temporal changes in the organic matter deposited in the mangrove of Jaguaripe estuary (BA, Brazil)

Todos os Santos Bay is the second largest bay of Brazil. In its south region, it is present the estuary of Jaguaripe river. This is a relative preserved estuary, that presents a large mangrove area. It is estimated that this type of ecosystem has the capacity to bury large amounts of organic matter (OM). This OM can be of autochthonous sources, like the mangrove vegetation and the phytoplankton, or allochthonous sources, as continental vegetation. Understanding the magnitude and dynamics of these sources is important within the context of the global carbon cycle. It can be accessed through the use of organic molecular markers, such as n-alkanes. The objective of the present study was to evaluate the temporal changes in the OM sources deposited in the Jaguaripe river mangrove (Bahia, Brazil). The composition variation of the n-alkanes (n-C₂₀ to n-C₃₅) was analyzed in sedimentary cores (n = 5) sampled in the region. The quantification of the n-alkanes was performed in a Gas Chromatography equipped with a Flame Ionization Detector (GC-FID). For, the concentrations of total n-alkanes in this core ranged from; 5.610 to 146.409 ng g^-1. Through the application of diagnostic ratios, it could be observed the main sources of OM for the region, changes over time, this is due to natural climatic events, which modify the vegetation around it, thus influencing the deposited terrigenous OM. The present dissertation was written in a manuscript format, that will be submitted to Organic Geochemistry (Qualis: A2 [Area: Geosciences, Quadrennium: 2013-2016], Impact Factor: 3.228). The specific summary of the article will be presented in its corresponding chapter.

 

PALAVRAS-CHAVES:

n-Alkanes; Organic matter; Mangroves

PÁGINAS: 58
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Oceanografia
SUBÁREA: Oceanografia Química
RESUMO:

Todos os Santos Bay is the second largest bay in Brazil. In its southern region, it is the estuary of Jaguaripe river. This is a relatively preserved estuary, that presents a large mangrove area. It is estimated that this type of ecosystem has the capacity to bury large amounts of organic matter (OM). This OM can be of autochthonous sources, like the mangrove vegetation and the phytoplankton, or allochthonous sources, as continental vegetation. Understanding the magnitude and dynamics of these sources is important within the context of the global carbon cycle. It can be accessed through the use of organic molecular markers, such as n-alkanes. The objective of the present study was to evaluate the temporal changes in the OM sources deposited in the Jaguaripe river mangrove (Bahia, Brazil). The composition variation of the n-alkanes (n-C₂₀ to n-C₃₅) was analyzed in sedimentary cores (n = 5) sampled in the region. The quantification of the n-alkanes was performed in a Gas Chromatography equipped with a Flame Ionization Detector (GC-FID). For, the concentrations of total n-alkanes in this core ranged from; 5.610 to 146.409 ng g^-1. Through the application of diagnostic ratios, it could be observed the main sources of OM for the region, changes over time, this is due to natural climatic events, which modify the vegetation around it, thus influencing the deposited terrigenous OM. The present dissertation was written in a manuscript format, that will be submitted to Organic Geochemistry (Qualis: A2 [Area: Geosciences, Quadrennium: 2013-2016], Impact Factor: 3.228). The specific summary of the article will be presented in its corresponding chapter.

MEMBROS DA BANCA:
Interno - 2134515 - ANA CECILIA RIZZATTI DE ALBERGARIA BARBOSA
Interno - 2349838 - MARIA DO ROSARIO ZUCCHI
Externo ao Programa - 1522396 - VANESSA HATJE