Biophysical interactions in the Cabo Frio upwelling system, southeastern Brazil

Abstract

A B S T R A C TThe rising of cold water from deeper levels characterizes coastal upwelling systems. This flow makes nutrients available in the euphotic layer, which enhances phytoplankton production and growth. On the Brazilian coast, upwelling is most intense in the Cabo Frio region (RJ). The basic knowledge of this system was reviewed in accordance with concepts of biophysical interactions. The high frequency and amplitude of the prevailing winds are the main factor promoting the rise of South Atlantic Central Water, but meanders and eddies in the Brazil Current as well as local topography and coast line are also important. Upwelling events are common during spring/summer seasons. Primary biomass is exported by virtue of the water circulation and is also controlled by rapid zooplankton predation. Small pelagic fish regulate plankton growth and in their turn are preyed on by predatory fish. Sardine furnishes an important regional fish stock. Shoreline irregularities define the embayment formation of the Marine Extractive Reserve of Arraial do Cabo making it an area with evident different intensities of upwelled water that harbors high species diversity. Consequently, on a small spatial scale there are environments with tropical and subtropical features, a point to be explored as a particularity of this ecosystem. R E S U M OOs sistemas costeiros de ressurgência são caracterizados pela ascensão de águas frias que tornam os nutrientes disponíveis na camada eufótica para o crescimento e aumento da produção fitoplanctônica. No Brasil, a região do Cabo Frio (RJ) é o principal sistema de ressurgência costeira. O objetivo desse artigo foi revisar o atual conhecimento desse sistema através dos conceitos sobre interações biofísicas. A ascensão da Água Central do Atlântico Sul ocorre devido à alta frequência e amplitude dos ventos, à presença de meandros e vórtices na Corrente do Brasil, além da topografia local e da linha de costa. Os eventos de ressurgência são comuns durante os períodos de primavera/verão e a biomassa primária é exportada devido à circulação da água, sendo também controlada pela rápida predação zooplanctônica. Os pequenos peixes pelágicos regulam o crescimento do plâncton e são consumidos pelos peixes predadores, resultando em um importante estoque pesqueiro regional. A irregularidade da costa define as enseadas do Cabo Frio, na Reserva Extrativista Marinha do Arraial do Cabo, apresentando distintas influências das águas ressurgidas e resultando em grande diversidade de espécies. Consequentemente, ambientes com características tropicais e subtropicais são observados dentro de uma pequena escala espacial, o que constitui uma particularidade desse ecossistema.

South Tropical Atlantic anti-phase response to Holocene Bond Events

“…The oceanographic system at the coring site has two main components: (1) the prevailing action of the Brazil and the North Brazil Currents (BC and NBC) that constitute low density tropical waters flowing south/southwest along the Brazilian coast partially over and mostly off the continental shelf; and (2) the South Atlantic Central Water (SACW) that rises at the coast coming from the west, which is most pronounced during austral spring and summer seasons (Coelho-Souza et al, 2012; (Fig. 1).…”

Bacterial and Archaeal Communities Variability Associated with Upwelling and Anthropogenic Pressures in the Protection Area of Arraial do Cabo (Cabo Frio region - RJ)

“…Samplings were done in the Marine Extractive Reserve of Arraial do Cabo (Fig. 1) where different degrees of the influence of upwelling are observed in a small spatial scale (Coelho-Souza et al 2012). Though Arraial do Cabo is a marine protected area, it suffers anthropogenic pressures such as harbor practices and sewage disposal (Ferreira et al 2004, Pereira et al 2010, Cury et al 2011.…”

Ecological distribution of Nematopalaemon schmitti and Exhippolysmata oplophoroides (Crustacea: Caridea) near an upwelling area off southeastern Brazil

“…The abiotic factors that shape the coexistence of the caridean shrimps are primarily controlled by habitat types and are influenced by seasonal water temperature changes, salinity fluctuations (Bilgin et al, 2008) and by water masses, through transport and accumulation of nutrients (Coelho-Souza et al, 2012). Sediment also plays an important role in the distribution of carideans because the sediment preferences are related to their burrowing ability (Pinn & Ansell, 1993).…”

“…Upwelling involves the ascent of cold, nutrient-rich water from subsurface layers to the surface, favoring primary production in the euphotic zone, where mass and energy are transferred through food webs; these physical processes highly impact marine life where they occur (Magliocca et al, 1979;Lehmann & Myrberg, 2008;Merino & MonrealGómez, 2009). As a result, upwelling regions are the most productive areas of the ocean (Coelho et al, 2012). The main upwelling area along the Brazilian Coast is off Cabo Frio, state of Rio de Janeiro (23°S), and occurs more frequently and intensely in spring (October to December) and summer (January to March) (Calado et al, 2008;Coelho-Souza et al, 2012).…”

“…As a result, upwelling regions are the most productive areas of the ocean (Coelho et al, 2012). The main upwelling area along the Brazilian Coast is off Cabo Frio, state of Rio de Janeiro (23°S), and occurs more frequently and intensely in spring (October to December) and summer (January to March) (Calado et al, 2008;Coelho-Souza et al, 2012). This phenomenon, when combined with the intrusion of South Atlantic Central Water (SACW) with temperatures below 20°C and salinities between 34.6 and 36.0 (Miranda, 1985), makes the Cabo Frio region and adjacent areas highly productive and important for the distribution and abundance of benthic communities (De Léo & Pires-Vanin, 2006).…”