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| Formato: | Artículo científico |
| Lenguaje: | en |
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Academia Brasileira de Ciências
2007
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| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=32779205 |
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- Palynological analysis of a sediment core obtained in Guanabara Bay, Rio de Janeiro, Brazil Cintia F. Barreto José A. Baptista Cynthia F.P. da Luz Claudia G. Vilela Ortrud M. Barth Multidisciplinaria (Ciencias Naturales y Exactas) pollen Guanabara Bay paleoenvironment Quaternary Palynology The sediment of a core collected about 2 km north of Paquetá Island, Guanabara Bay, was submitted to pollen analysis,in order to recognize the dynamics of the regional vegetation, and the anthropic influence. Radiocarbon dating of asample next to the bottom of the core indicates an age of 4.210 ± 40 14C yrs B.P (calibrated age). It was possibleto establish four palynological zones. Starting at the bottom of the core, a decrease in palynomorph concentration,the presence of degraded pollen grains and spores, and the predominance of ombrophilous forest pollen grains wereobserved in the basal portion of Zone I. These data may indicate the presence of an exuberant Atlantic Forest, dominatedby a marine regressive event. The concentration of well-preserved palynomorphs increased in Zone II, with thepredominance of the ombrophilous forest vegetation also, and an expressive increase of hygrophytes, indicating morehumid environmental conditions. Palynomorph concentration decreased again toward the top of Zone III, and the fieldvegetation was predominant. In the upper Zone IV occurred a strong decrease in pollen and spore concentration, withpredominance of field vegetation also, and the appearance of exotic pollen grains, showing the anthropic influenceat this time 2007 artículo científico 0001-3765 https://www.redalyc.org/articulo.oa?id=32779205 en http://www.redalyc.org/revista.oa?id=327 Anais da Academia Brasileira de Ciências application/pdf Academia Brasileira de Ciências Anais da Academia Brasileira de Ciências (Brasil) Num.2 Vol.79