Resumen
Observations in a mangrove lined coast in south-western Puerto Rico (rainfall 800-1,000 mm; evaporation 1,900-2,200 mm; mean annual temperature 25º C; and average tidal range 0.3 m) have shown that the degree of structural development of the mangrove forest is closely related to wave exposure. In exposed coastal segments, sand berms formed by wave action within the outer fringe prevent water flow towards the inner forest, resulting in high salinities. The berms are higher in areas where the outer mangrove fringe has been destroyed by storms or other causes. Dead mangrove stands are found behind these areas and salinities reach 75-80‰ We suggest that the mangrove fringe contributes to dissipate wave energy over a broad area which reduces the high of the berm. The presence of absence of "blowholes" in the seagrass Thalassia; bed is an index of the degree of protection that the coast receives. The "thickness" of the mangrove fringe is also related to the degree of shelter: it is "thin" in high energy segments, "thick" in coastal segments subject to intermediate energy and "thin"again in the most sheltered locations. In the outlying cays mangrove development follows a similar pattern: the outer exposed cays (essentially coral islands mantled by coarse sands) are devoid of mangrove cover or have stunted trees (generally Laguncularia; canopy height, 2 m). Islands which are less exposed are colonized by Rhizophora which frequently forms overwashed forests (canopy height, 8-9 m). In the most seltered areas, Rhizophora colonizes the shallow banks, forming islands which soon develop an inner hypersaline lagoon due to the accumulation of material in the outer edges and the accumulation of salt in the interior. The wave energy level reaching a given section of the coast is therefore an important factor which determines the degree of structural development of the mangrove forest. High energy levels are associated with erosion, destruction or deposition of berms which affect mangrove development. Low energy levels, however, are associated with a rapid process of island maturation, aging and death due to rapid salt accumulation.
ARTIGOS
Ecologia del manglar en una zona arida: exposicion al oleaje y estructura del manglar
Gilberto Cintrón; Carlos Goenaga; José Gonzáles-Liboy
Departamento de Recursos Naturales, Area de Investigaciones Científicas, San Juan, Estado Libre Asociado de Puerto Rico
SYNOPSIS
Observations in a mangrove lined coast in south-western Puerto Rico (rainfall 800-1,000 mm; evaporation 1,900-2,200 mm; mean annual temperature 25º C; and average tidal range 0.3 m) have shown that the degree of structural development of the mangrove forest is closely related to wave exposure. In exposed coastal segments, sand berms formed by wave action within the outer fringe prevent water flow towards the inner forest, resulting in high salinities. The berms are higher in areas where the outer mangrove fringe has been destroyed by storms or other causes. Dead mangrove stands are found behind these areas and salinities reach 75-80 We suggest that the mangrove fringe contributes to dissipate wave energy over a broad area which reduces the high of the berm. The presence of absence of "blowholes" in the seagrass Thalassia; bed is an index of the degree of protection that the coast receives. The "thickness" of the mangrove fringe is also related to the degree of shelter: it is "thin" in high energy segments, "thick" in coastal segments subject to intermediate energy and "thin"again in the most sheltered locations. In the outlying cays mangrove development follows a similar pattern: the outer exposed cays (essentially coral islands mantled by coarse sands) are devoid of mangrove cover or have stunted trees (generally Laguncularia; canopy height, 2 m). Islands which are less exposed are colonized by Rhizophora which frequently forms overwashed forests (canopy height, 8-9 m). In the most seltered areas, Rhizophora colonizes the shallow banks, forming islands which soon develop an inner hypersaline lagoon due to the accumulation of material in the outer edges and the accumulation of salt in the interior. The wave energy level reaching a given section of the coast is therefore an important factor which determines the degree of structural development of the mangrove forest. High energy levels are associated with erosion, destruction or deposition of berms which affect mangrove development. Low energy levels, however, are associated with a rapid process of island maturation, aging and death due to rapid salt accumulation.
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Referencias Bibliográficas
CHAPMAN, V. J. 1976. Mangrove vegetation. Germany, J. Cramer, 447p.
CINTRÓN, G.; LUGO, A. E.; POOL, D. J. & MORRIS, G. 1975. Los manglares de las costas áridas de Puerto Rico. II Simposio Latinoamericano de Oceanografía Biológica, vol. 2, p.137-150. Cumaná. Universidad de Oriente.
______. 1978. Mangroves of arid environments in Puerto Rico and adjacentes islands. Biotrópica, 10(2):110-121.
______ & GOENAGA, C. 1977. Observaciones sobre las franjas de manglar en zonas áridas. IV Simpósio Latinoamericano de Oceanografía Biológica Guayaquil, Ecuador, (en preparación).
DAVIS, J. H. 1940. The ecology and geologic role of mangroves in Florida. Publs, Carnegie lnstn, (517):303-312. (Papers from the Tortugas Lab., 32).
FOLK, R. L. 1974. Petrology of sedimentary rocks. Austin, Texas, Hemphill Publ. Co., 182p.
GLYNN, P. W.; ALMODÓVAR, L. R. & GONZÁLEZ, J. G. 1964. Effects of hurricane Edith on marine life in la Parguera, Puerto Rico. Carib. J. Sci., (4):335-345.
LUGO, A. E. & CINTRÓN, G. 1975. The mangrove forests of Puerto Rico and their management. In: Walsh, G.; Snedaker, S. & Teas, H., eds. - Proc. Int. Symp. Biol, and Managment of Mangroves. Gainesville, Inst. Food Agr. Sci./Univ. of Florida, p.825-846.
MARGALEF, R. 1962. Comunidades naturales. Publnes esp. Inst. Biol, mar., Univ. Puerto Rico, 469p.
NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION. 1978. Tides tables high and low water predictions 1978. East coast of North and South America including Greenland. U.S. Department of Commerce.
STODDART, D. R. 1962. Three Caribbean atolls: Turneffe Islands, Lighthouse Reef, and Glover's Reef, British Honduras. Atoll Res. Bull., (87):1-151.
U.S. NAVAL OCEANOGRAPHIC OFFICE. 1958. Sailing directions for the West Indies. Publs. U.S. hydrogr. Off., 1(21):1-557.
______. 1962. Oceanographie atlas of the North Atlantic Ocean, Section IV, Sea and Swell. Publs. U.S. hidrogr. Off., (700):1-227.
WELCH, B. L. 1962. Aspects of succession in shallow coastal waters of the Caribbean. Ph. D. Dissertation. Duke University. Ann Arbor, Univ. Microfilms, Inc., 126p.
- CHAPMAN, V. J. 1976. Mangrove vegetation. Germany, J. Cramer, 447p.
- CINTRÓN, G.; LUGO, A. E.; POOL, D. J. & MORRIS, G. 1975. Los manglares de las costas áridas de Puerto Rico. II Simposio Latinoamericano de Oceanografía Biológica, vol. 2, p.137-150. Cumaná. Universidad de Oriente.
- ______. 1978. Mangroves of arid environments in Puerto Rico and adjacentes islands. Biotrópica, 10(2):110-121.
- ______ & GOENAGA, C. 1977. Observaciones sobre las franjas de manglar en zonas áridas. IV Simpósio Latinoamericano de Oceanografía Biológica Guayaquil, Ecuador, (en preparación).
- DAVIS, J. H. 1940. The ecology and geologic role of mangroves in Florida. Publs, Carnegie lnstn, (517):303-312. (Papers from the Tortugas Lab., 32).
- FOLK, R. L. 1974. Petrology of sedimentary rocks. Austin, Texas, Hemphill Publ. Co., 182p.
- GLYNN, P. W.; ALMODÓVAR, L. R. & GONZÁLEZ, J. G. 1964. Effects of hurricane Edith on marine life in la Parguera, Puerto Rico. Carib. J. Sci., (4):335-345.
- LUGO, A. E. & CINTRÓN, G. 1975. The mangrove forests of Puerto Rico and their management. In: Walsh, G.; Snedaker, S. & Teas, H., eds. - Proc. Int. Symp. Biol, and Managment of Mangroves. Gainesville, Inst. Food Agr. Sci./Univ. of Florida, p.825-846.
- MARGALEF, R. 1962. Comunidades naturales. Publnes esp. Inst. Biol, mar., Univ. Puerto Rico, 469p.
- NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION. 1978. Tides tables high and low water predictions 1978. East coast of North and South America including Greenland. U.S. Department of Commerce.
- STODDART, D. R. 1962. Three Caribbean atolls: Turneffe Islands, Lighthouse Reef, and Glover's Reef, British Honduras. Atoll Res. Bull., (87):1-151.
- U.S. NAVAL OCEANOGRAPHIC OFFICE. 1958. Sailing directions for the West Indies. Publs. U.S. hydrogr. Off., 1(21):1-557.
- ______. 1962. Oceanographie atlas of the North Atlantic Ocean, Section IV, Sea and Swell. Publs. U.S. hidrogr. Off., (700):1-227.
- WELCH, B. L. 1962. Aspects of succession in shallow coastal waters of the Caribbean. Ph. D. Dissertation. Duke University. Ann Arbor, Univ. Microfilms, Inc., 126p.
Fechas de Publicación
-
Publicación en esta colección
06 Jun 2012 -
Fecha del número
1980
