Pará mangroves (Biodiversity)

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The mangroves of the Pará ecoregion are particularly diverse because they are found in a zone of transition between true mangroves, and those that include freshwater species associated with the Amazon floodplain. Like other mangrove ecoregions on the north coast of Brazil, they are exceptionally well developed, reaching heights of up to 45 meters (m) because of high inputs of freshwater from rainfall and from the most extensive river system in the world. They can also be found far inland because of flat topography and a high tidal range.

Location and General Description

This tropical ecoregion holds the mangrove patches around the mouth of the Amazon, Baía de Marajó extending north to Cabo Caciporé including the Parque National de Cabo Orange. Its terrain is composed of fine grained clay and sediment deposited by the Amazon River, which form hundreds of islands and mudflats that are continuously colonized and stabilized by the salt tolerant mangrove species. High tidal ranges of 5-7 m, combined with flat topography, allow the mangroves to extend up to 45 kilometers (km) inland from the coast. The climate is humid tropical, with temperatures ranging between 24°C and 32°C. Exceptional development of the mangroves is also made possible by high freshwater inputs from rainfall that averages 2,500 millimeters (mm) a year but may be as high as 4,000 mm a year, and from the Amazon River system. Although well developed, the distribution of mangroves in this ecoregion is somewhat restricted by the presence of freshwater species, that include typical Amazon freshwater hardwoods.

Biodiversity Features

Rhizopora mangle is the most frequently occurring mangrove species and is found closest to the coast at heights of up to 25 m. Also particularly well developed along the north coast of Brazil is Avicennia germinans and A. schaueriana, which may be over 1 meter in diameter and reach heights of up to 45 meters. R. racemosa, R. harrisonii, Laguncularia racemosa, and Conocarpus erectus are found in the transition zone, leading to dry forest areas. Non-tree species associated with these mangroves are Spartina alterniflora that grows on the seaward fringe, and Hibiscus tiliaceus and the fern Acrostichum aureum, that are both found in the landward margins and dry saline areas within the mangroves. Species found associated with these mangroves because of their location adjacent to tropical forests and because of high freshwater input include the tropical forest species, leguminosae vine (Dalbergia brownei), and Apocynaceae liana (Rhabdadenia biflora); freshwater macrophytes, Araceae Montrichardia arborescens, and Leguminosae Mora oleifera; and palm species, Euterpe oleracea and Orbygnia martiana.

Rare and endangered species found in this ecoregion include the birds, scarlet ibis (Eudocimus ruber), and wattled jacana (Jacana jacana), the mammals tucuxi (Sotalia fluviatilis) and manatee (Trichechus manatus), and two marine turtles, the green turtle (Chelonia mydas) and the leatherback (Dermochelys coriacea).

Current Status

This ecoregion contains approximately 28% of the total [[Brazil]ian] mangrove area, much of which is intact because of low population density and inaccessibility. However, the region also includes the urban area of Belém, where much of the region's population is concentrated. There are 5 environmental protection areas in this coastal zone but it is not clear what percentage of these consist of mangroves.

Types and Severity of Threats

The main economic activities associated with environmental risks and concerns are of the ecoregion are subsistence agriculture, extensive grazing of livestock, tourism, timber extraction, mineral exploration, commercial and industrial development, land speculation in conservation areas, development of transportation infrastructure that involves the filling of mangrove areas, and urban expansion into mangrove areas. These mangroves are also important to the subsistence economy of numerous artisanal fishermen, particularly for their abundance of crabs. In addition to fishing, mangroves are used as timber for construction of boats and houses, and their barks as a source of tannin used to dye ship sails. They are also used for firewood and charcoal.

Justification of Ecoregion Delineation

Classification and linework for all mangrove ecoregions in Latin America and the Caribbean follow the results of a mangrove ecoregion workshop and subsequent report.

Additional Information on this Ecoregion

Further Reading

  • Diegues, A., Harris G., Moreira A.C. 1995. Marine region 9: South Atlantic]. In: Great Barrier Reef Marine Park Authority, The World Bank, and The World Conservation Union. A global representative system of marine protected areas. Volume 2: Wider Caribbean, West Africa and South Atlantic. The World Bank Environment Department, Washington D.C.
  • Dunning, J.S. 1987. South American birds: a photographic aid to identification. Harrowood Books, Newton Square PA. ISBN: 0915180251
  • Ecoregional Workshop: A Conservation Assessment of Mangrove Ecoregions of Latin America and the Caribbean. 1994. Washington D.C., World Wildlife Fund.
  • Eisenberg, J.F., and K.H. Redford. 1999. Mammals of the neotropics: the central neotropics. Volume 3: Ecuador, Peru, Bolivia, Brazil. The University of Chicago Press, Chicago and London. ISBN: 0226195422
  • Kjerfve, B., and L.D. Lacerda. 1993. Mangroves of Brazil. In: Lacerda L.D., editor, Conservation and sustainable utilization of mangrove forests in Latin America and Africa Regions. Part I: Latin America. International Society for Mangrove Ecosystems and the International Tropical Timber Organization.
  • Olson, D.M., E. Dinerstein, G. Cintrón, and P. Iolster. 1996. A conservation assessment of mangrove ecosystems of Latin America and the Caribbean. Final report for The Ford Foundation. World Wildlife Fund, Washington, D.C.
  • Schaeffer-Novelli, Y. 1999. (Consultora). Evaluation and priority actions for the conservation of the biodiversity of the marine and coastal zone. PRONABIO Projeto de conservação e utilização sustentável da diversidade biológica Brasileira - PROBIO. São Paulo, Brasil. Meio Ambiente.
  • Sick, H. 1993. Birds in Brazil: a natural history. Princeton University Press, Princeton NJ. ISBN: 0691085692
  • Ubiratan Moreira dos Santos, J., I. de Sousa Gorayeb, M. de Nazaré do Carmo Bastos 1999. Avaliação e ações prioritarias Pará a conservação da biodiversidade da zona costeira e marinha. Diagnóstico da situação Pará a conservação da biodiversidade da zona costeira e marinha amazônica. Ministerio do Meio Ambiente and Projecto de Conservação e Utilização Sustantável da Diversidadie Biológica Brasiliera. Belém, Pará, Brasil.



Disclaimer: This article is taken wholly from, or contains information that was originally published by, the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.

Citation

Fund, W. (2007). Pará mangroves. Retrieved from http://editors.eol.org/eoearth/wiki/Pará_mangroves_(Biodiversity)