Late Holocene evolution and increasing pollution in Guanabara Bay, Rio de Janeiro, SE Brazil

Abstract. In contrast to its small surface area, the coastal zone plays a disproportionate role in the global carbon cycle. Carbon production, transformation, emission and burial rates at the land–ocean interface are still poorly known, especially in tropical regions. Surface water pCO2 and ancillary parameters were monitored during nine field campaigns between April 2013 and April 2014 in Guanabara Bay, a tropical eutrophic to hypertrophic semi-enclosed estuarine embayment surrounded by the city of Rio de Janeiro, SE-Brazil. Water pCO2 varied between 22 and 3715 ppmv in the Bay showing spatial, diurnal and seasonal trends that mirrored those of dissolved oxygen (DO) and Chlorophyll a (Chl a). Marked pCO2 undersaturation was prevalent in the shallow, confined and thermally stratified waters of the upper bay, whereas pCO2 oversaturation was restricted to sites close to the small river mouths and small sewage channels, which covered only 10% of the bay's area. Substantial daily variations in pCO2 (up to 395 ppmv between dawn and dusk) were also registered and could be integrated temporally and spatially for the establishment of net diurnal, seasonal and annual CO2 fluxes. In contrast to other estuaries worldwide, Guanabara Bay behaved as a net sink of atmospheric CO2, a property enhanced by the concomitant effects of strong radiation intensity, thermal stratification, and high availability of nutrients, which promotes phytoplankton development and net autotrophy. In the inner part of the bay, the calculated annual CO2 sink (−19.6 mol C m2 yr-1) matched the organic carbon burial in the sediments reported in the literature. The carbon sink and autotrophy of Guanabara Bay was driven by planktonic primary production promoted by eutrophication, and by its typology of marine embayment lacking the classical extended estuarine mixing zone, in contrast to river-dominated estuarine systems, which are generally net heterotrophic and CO2 emitters. Our results show that global CO2 budgetary assertions still lack information on tropical estuarine embayments and lagoons, which are affected by thermal stratification and eutrophication and behave specifically with respect to atmospheric CO2.

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A mid-Holocene vegetational and anthropogenic record in the Guanabara Bay region, Rio de Janeiro State, SE Brazil, assessed by palynological and charcoal data

Grana ◽

10.1080/00173134.2016.1238958 ◽

2016 ◽

Vol 56 (4) ◽

pp. 304-314 ◽

Cited By ~ 2

Author(s):

Cintia F. Barreto ◽

Alex Da S. De Freitas ◽

Taísa Camila S. De Souza ◽

Claudia G. Vilela ◽

Ortrud M. Barth ◽

...

Keyword(s):

Rio De Janeiro ◽

Guanabara Bay ◽

Se Brazil ◽

Janeiro State

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Palynological studies of Late Holocene Jurujuba Sound sediments (Guanabara Bay), Rio de Janeiro, southeast Brazil

CATENA ◽

10.1016/j.catena.2014.10.028 ◽

2015 ◽

Vol 126 ◽

pp. 20-27 ◽

Cited By ~ 8

Author(s):

Cintia Ferreira Barreto ◽

José Antônio Baptista Neto ◽

Claudia Gutterres Vilela ◽

Ortrud Monika Barth

Keyword(s):

Rio De Janeiro ◽

Late Holocene ◽

Guanabara Bay ◽

Southeast Brazil

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Categorias analíticas do espaço e Turismo: o exemplo da Fortaleza de Santa Cruz, Niterói/RJ

GEOgraphia ◽

10.22409/geographia2006.816.a13523 ◽

2010 ◽

Vol 8 (16) ◽

Author(s):

Miguel Ângelo Ribeiro

Keyword(s):

Social Sciences ◽

Urban Space ◽

Rio De Janeiro ◽

Future Generations ◽

Guanabara Bay ◽

Single Family ◽

Spatial Dynamic ◽

Santa Cruz ◽

Military Installations ◽

The City

O objetivo que permeia a presente pesquisa é utilizar a Fortaleza de Santa Cruz, localizada no bairro de Jurujuba, em Niterói, construída em 1555, na entrada da barra da Baía de Guanabara, como foco de antílise, ressaltando a importância deste fixo social enquanto atração turística e de lazer, incluindo a cidade de Niterói no circuito destas atividades, complementares à cidade do Rio de Janeiro; além de abordar conceitos e categorias analíticas, oriundos das ciências sociais, principalmente provenientes da Geografia, pertinentes ao estudo das atividades em tela. Neste contexto, na dinâmica espacial da cidade de Niterói, o processo de mudança de função dos fixos sociais têm sido extraordinário. Residencias unifamiliares, prédios e até mesmo fortificações militares, verdadeiras monumentalidades, foram refuncionalizadas, passando por um processo de turistificação. Assim, a refuncionalização da respectiva Fortaleza em espaço cultural toma-se um importante atrativo da história, do patrimônio, da cultura, marcando no espaço urbano sua expressões e monumentalidade, criada pelo homem como símbolo de seus ideais, objetivos e atos, constituindo-se em um legado as gerações futuras, formando um elo entre passado, presente e futuro. Abstract This paper focuses on Santa Cruz Fortress, built in 1555 in Jurujuba (Niterói), to guard the entrance of Guanabara bay, and stresses its role as a towist attraction and leisure' area, as a social fix which links the city of Niterói to the complementary circuit of these activities in the city of Rio de Janeiro. The study uses important concepts and analytic categories fiom social sciences, particularly fiom Geography.In the spatial dynamic of the city of Niterói, change in functions of social fuces has been extraordinary. Single-family dwellings, buildings and even military installations have been re-functionalized, undergoing a process of touristification. In that way, the refunctionalization of the Fortress as a cultural space provides an important attraction in the domains of history, patrimony, and culture, providing the urban space with an expression of monumentality, created by man as a symbol of his ideals, aims and actions, a legacy to future generations forming a link between past, present and future.

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