North Brazil Shelf large marine ecosystem

July 12, 2012, 3:09 pm
Source: NOAA
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caption Location of the North Brazil Shelf Large Marine Ecosystem. (Source: NOAA)

 

The North Brazil Shelf Large Marine Ecosystem (LME) is characterized by its tropical climate. It extends in the Atlantic Ocean from the boundary with the Caribbean Sea to the Paraiba River estuary in Brazil. The LME owes its unity to the North Brazil Current, which flows parallel to Brazil’s coast and is an extension of the South Equatorial Current coming from the East. The LME is characterized by a wide shelf, and features macrotides and upwellings along the shelf edge. It has moderately diverse food webs and high production.

This LME has high levels of nutrients coming from the Amazon and Tocantins rivers, as well as from the smaller rivers of the Amapa and western Para coastal plains. It is bordered by 4 countries: Brazil, French Guiana, Suriname and Guyana. LME book chapters and articles pertaining to the South Brazil Shelf include Bakun, 1993, and Ekau and Knoppers, 2003.

Productivity

For a map of the North Brazil Shelf LME, and for more information on coastal topography, water masses, currents, sediments and plankton characteristics, see Ekau and Knoppers, 2003. The LME is one of the few areas of the world where an open, passive margin is almost completely covered by biogenic carbonate sediments (see Summerhayes et al., 1975). The North Brazil Shelf LME is considered a Class I, highly productive (>300 gC/m2-yr), ecosystem based on SeaWiFS global primary productivity estimates. The LME is the most productive region of the Brazilian shelf. It has a high number of species of amphibians, birds and reptile species. Brazil’s coral fauna is notable for having a low species diversity yet a high degree of endemism. The Amazon River and its extensive plume are the main source of nutrients for the LME. Studies of the primary productivity of this region have so far been scant. There are no integrated estimates of the water column. For community analyses of macrozooplankton, see Schwamborn et al., 1999a.

Fish and Fisheries

 

caption An image of a coastline in the North Brazil Shelf LME. (Source: NOAA)

 

The general greater marine biodiversity of this tropical region is reflected in catch composition. There is a high catch percentage of coastal and pelagic fishes, as well as catches of herrings, sardines, anchovies and crustaceans (crabs, lobsters, shrimp). However, information on the exploitation of Brazilian fish stocks is not available for all areas and species. For more information on fisheries yields and composition, see Ekau and Knoppers, 2003. Fish catches are low, and fisheries are dominated by artisanal fishing methods. The Global International Waters Assessment (GIWA) has issued a matrix that ranks LMEs according to the sustainable exploitation of fisheries and the predicted direction of future changes. GIWA characterizes the LME as severely impacted in terms of overfishing and destructive fishing practices. These impacts, however, are thought to be decreasing. In the Sao Francisco area, overfishing is increasing (see the GIWA web site). Fisheries in this LME are managed by CEPNORTE, a department of the Brazilian Institute of Environment and Natural Renewable Resources responsible for the northern coast from Cape Orange to Rio Paranaiba. Brazil is expending great efforts to assess the state of the living and non-living resources of its Exclusive Economic Zone. REVIZEE is a Brazilian program presently assessing the sustainable living resources of the EEZ. See Food and Agriculture Organization (FAO) statistics for fisheries yields (FAO, 2000). The University of British Columbia Fisheries Center has detailed fish catch statistics for this LME.

Pollution and Ecosystem Health

Areas of global concern are climate change, biodiversity, and ozone depletion. The Global International Waters Assessment (GIWA) has issued a matrix that ranks LMEs according to the sustainable exploitation of fisheries and the predicted direction of future changes. GIWA characterizes the LME as severely impacted in terms of loss of ecotones, and socioeconomic and community impacts. These impacts are thought to be increasing (see the GIWA web site). The Amazon River and its basin play a central role in regulating the Earth’s hydrologic cycle, as well as providing habitats to unique plants and animal species. The Amazon’s biodiversity and habitats are under threat as a result of illegal logging (deforestation) and mining in the Amazon basin. Artisanal and small-scale gold mining in the Amazon basin uses a mercury-based amalgamation process with negative results for the environment and human health. The mercury released into the air in the form of vapor or lost in the rivers and soil is a pollutant causing concern because of the long-term impact on habitats and human health. The technology used by the artisanal miners remains unchanged. Other threats to the LME are due to changes in the local population and development pressures associated with urban and industrial development. There is increasing boat traffic on the Amazon and coastal pollution. Poaching is an issue in the Pantanal wetlands, an area of significant biodiversity. The northern coastline has mangrove estuaries that are threatened by human interventions. There is some coral bleaching associated with climate change. Agricultural production in the area makes use of fertilizers and pesticides, which eventually end up in the coastal environment.

Socioeconomics

 

caption Brazil. (Source: NOAA)

 

Human uses include subsistence agriculture (rice, corn, cassava and beans), fisheries (mostly artisanal and focused on shrimp), and the exploitation of gold in the Amazon Basin. Logging and mining are taking place in the Amazon basin. There is coastal exploitation of clay and sand, and limited ecotourism. Minke whales were harvested in the 1980s. In French Guiana, fisheries, crops (cultivated in the coastal areas), and natural resources such as gold and bauxite are the main economic activities. Suriname has a great diversity of flora and fauna, which would point to ecotourism as a possible economic activity. In Guyana, bauxite and agriculture are the main economic activities. See above for GIWA’s assessment of the socioeconomic impacts of pollution.

Governance

This LME is bordered by the Brazilian states of Amapa, Para and Maranhao, and by French Guiana, Suriname and Guyana. In terms of fisheries management in Brazil, CEPNORTE is responsible for the northern coast from Cape Orange to Rio Paranaiba. Transboundary issues needing to be addressed are land degradation and water pollution caused by mining activities. Recently, a Global Environmental Facility (GEF) project is working with the United Nations Industrial Development Organization (UNIDO) to formulate a global action plan for countries, including Brazil, that pollute their waters with mercury used as part of the process of artisanal gold mining. Brazil has an ongoing program for coastal zone management (see GERCO-PNMA, 1996). Brazil has established 3 marine parks in this LME. The Parque Estadual Marinho do Parcel Manoel Luis, in the State of Maranhao, includes 3 coral banks off the northern coast of Maranhão, at the northern distribution limit of several fish species that are endemic to the Brazilian coast. The area is very important for fishery production and is of great scientific value. The Reentrancias Maranhenses, in Maranhão, is a shorebird reserve in a complex estuarine system of islands, bays, coves, and mangrove forests. The site is of great importance for numerous species of fish, shellfish, migratory birds and manatees. The Baixada Maranhense Environmental Protection Area, also in Maranhão, is a seasonally flooded coastal land with gallery forests and mangrove swamps.

References

Articles and LME Volumes

  • Bakun, A., 1993. The California Current, Benguela Current, and Southwestern Atlantic shelf ecosystems: A comparative approach to identifying factors regulating biomass yields. In: Sherman, K.; Alexander, L.M.; Gold, B.D. (eds.), Large marine ecosystems: stress, mitigation and sustainability of large marine ecosystems. AAAS Publication, 92-39S: 199-224.
  • Ekau, W. and B. Knoppers, 2003. A review and redefinition of the large marine ecosystems of Brazil. In: K. Sherman and G. Hempel (eds.). Large Marine Ecosystems of the World --Trends in Exploitation, Protection and Research. Elsevier Science. Amsterdam. ISBN: 0444510273.
  • Prescott, J.R.V. 1989. The political division of large marine ecosystems in the Atlantic Ocean and some associated seas. In K. Sherman and L.M. Alexander, eds. Biomass Yields and Geography of Large Marine Ecosystems. AAAS Selected Symposium 111. Westview Press, Boulder CO. 395-442. ISBN: 0813378443.

Other References

  • Bakun, A. and Parrish, R.H., 1991. Comparative studies of coastal pelagic fish reproductive habitats: the anchovy (Engraulis anchoita) of the southwestern Atlantic. ICES J. mar. Sci., 48: 343-361.
  • Bonecker, S.L.C.; Bonecker, A.C.T.; Nogueira, C.R.; Reynier, M.V., 1991: Zooplâncton do litoral norte do Espírito Santo - Brasil: estrutura espaço-temporal. Anais do IV Encontro Brasileiro do Plâncton, Recife, UFPE: 369-391.
  • Castro, B.M.; Miranda, L.B., 1998: Physical oceanography of the western Atlantic continental shelf located between 4°N and 34°S. In: Robinson, A.R.; Brink, K.H. (eds.): The Sea, Vol. 11: 209-252, New York, John Wiley & Sons. ISBN: 0674017412.
  • Dias-Neto, J.; Mesquita, J.X., 1988: Potencialidade e explotação dos recursos pesqueiros do Brasil. Ciência e Cultura, São Paulo, 40(5): 427-441.
  • Dominguez, J.M.L.; Bittencourt, A.C., 1996: Regional Assessment of Long-term trends of coastal erosion in northeastern Brazil. An. Acad. bras. Ci., 68(3): 355-371.
  • Ekau, W.1999: Topographical and hydrographical impacts on macrozooplankton community structure in the Abrolhos Bank region, East Brazil. Arch.Fish.Mar.Res. 47(2/3), 307-320.
  • Ekau, W.; Knoppers, B., 1999: An introduction to the pelagic system of the North-East and East Brazilian shelf. Arch.Fish.Mar.Res. 47(2/3), 113-132.
  • Ekau, W.; Matsuura, Y., Torbohm-Albrecht, s., 1996: Diversity and distribution of macrozooplankton in the eastern continental shelf waters off East Brazil. in: Ekau, W.; Knoppers, B.A., 1996 (eds.): Sedimentation processes and productivity in the continental shelf waters off east and Northeast Brazil. Cruise Report and first results of the Brazilian German project JOPS-II (Joint Oceanographic Projects). Center for Tropical Marine Ecology, Bremen: 139-147.
  • Ekau, W.; Westhaus-Ekau, P.; Medeiros, C., 1999: Large Scale Distribution of Fish Larvae in the Continental Shelf Waters off NE-Brazil. Arch.Fish.Mar.Res. 47(2/3), 183-200.
  • Emílsson, I. 1959: Alguns aspectos físicos e químicos das águas marinhas brasileiras. Ciência e Cultura, S.Paulo, 11(2):44-54.
  • FAO, 2000:Fishery statistics. FAO yearbook vol 86/1 1998, FAO, Rome.
  • GERCO-PNMA, 1996: Macrodiagnóstico da zona costeira do Brasil na escala da união. - Gerenciamento Costeiro, Programa Nacional do Meio Ambiente, MMA (Ministério do Meio Ambiente,UFRJ, SUJD, LAGEJ, Brasilia: 280 pp.
  • Geyer, W.R.; Beardsley, R.C.; Candela, J.; Castro, B.M.; Legeckis, R.V.; Lentz, S.J.; Limeburner, R.; Miranda, L.B.; Trowbridge, J.H., 1991: The physical oceanography of the Amazon outflow. Oceanography, 4(1): 8-14.
  • Johns, W.E.; Lee, T.N.; Schott, F.A.; Zantopp, R.J.; Evans, R.H., 1990: The North Brazil Current retroflection: seasonal structure and eddy variability. J. Geophys. Res., 95(C12): 22103-22120.
  • Kjerfre, B.; Lacerda, L.D., 1990: Mangroves of Brazil. In: Lacerda, L.D. (ed.): Conservation and sustainable utilization of mangrove forests in Latin America and Africa regions. Part I - Latin America. ITTO/ISMA Project PD 114/90: 245-271.
  • Knoppers, B.; Ekau, W.; Figueiredo, A.G., 1999a: The coast and shelf of east and northeast Brazil and material transport. Geo-Marine Letters 19: 171-178.
  • Medeiros, C.; Macedo, S.; Feitosa, F.A.N.; Koening, M.L., 1999: Hydrology and phytoplankton biomass of the northeastern Brazilian waters. Arch.Fish.Mar.Res. 47(2/3), 133-151.
  • Neumann-Leitão, S.; Gusmão, L.M.deO.; Silva, T.A.; Nascimento-Vieira, D.A. do; Silva, A.P., 1999: Mesoplankton biomass and diversity of coastal and oceanic waters off Northeastern Brazil. Arch.Fish.Mar.Res. 47(2/3), 153-165. NOAA. 1991. Report of the ad hoc Committee on Large Marine Ecosystems. NOAA Technical Memorandum NMFS-F/NEC-92, 19p.
  • Richardson, P.; Hufford, G.E.; Limeburner, R. 1994: North Brazil current retroflection eddies. J. Geophysical Res. 99: 5081-5093
  • Schwamborn, R., Ekau, W., Pinto, A., Silva, T., Saint-Paul, U., 1999a: The contribution of estuarine decapod larvae to marine macrozooplankton communities in Northeast Brazil. Arch.Fish.Mar.Res. 47(2/3), 167-182.
  • Schwamborn, R., Voss, M., Ekau, W., Saint-Paul, U., 1999b: Stable isotope composition of particulate organic matter and zooplankton in northeast Brazilian shelf waters. Arch.Fish.Mar.Res. 47(2/3), 201-222.
  • Smith, W.O.; Demaster, D.J., 1996: Phytoplankton biomass and productivity in the Amazon river plume: correlation with seasonal river discharge. Cont. Shelf Res., 16(3): 291-319.
  • Stuhr, A. 1996: Phytoplankton production measurements. In: Ekau, W.; Knoppers, B.A., 1996 (eds.): Sedimentation processes and productivity in the continental shelf waters off east and Northeast Brazil. Cruise Report and first results of the Brazilian German project JOPS-II (Joint Oceanographic Projects). Center for Tropical Marine Ecology, Bremen: 83-85
  • Summerhayes, C.P.; Coutinho, P.N.; França, A.M.C.; Ellis, J.P., 1975: Salvador to Fortaleza, Northeastern Brazil. In: Upper Continental Margin sedimentation off Brazil. Stuttgart: Contribution to Sedimentology 4: 44-77. ISBN: 3510570049.
  • Teixeira, C.; Gaeta, S.A., 1991: Contribution of picoplankton to primary production in estuarine, coastal and equatorial waters of Brazil. Hydrobiologia, 209: 117-122.

 

 

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Citation

(2012). North Brazil Shelf large marine ecosystem. Retrieved from http://www.eoearth.org/view/article/51cbee857896bb431f69871d

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