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Gametogenesis in Madracis decactis Lyman, 1859 (Cnidaria, Scleractinia) from Ilha Grande Bay (Rio de Janeiro), southeastern Brazil
Muramatsu, Daniela;Silveira, Fábio Lang da;
Brazilian Journal of Oceanography , 2008, DOI: 10.1590/S1679-87592008000400005
Abstract: collections were made every two months in ilha grande bay, rio de janeiro, for 21 months (august/2004-may/2006) to study the gametogenesis of madracis decactis lyman, 1859. a total of 1800 polyps were examined using standard histological techniques. madracis decactis is a hermaphroditic species whose male and female gametes develop within different mesenteries. oogenesis begins in october, while spermatogenesis begins at the end of february, both reaching maturity at the end of april. the peak of reproductive activity occurred between february and april, when all the polyps were fertile, containing mainly stage iii oocytes. examination of fertile polyps indicated the simultaneous presence of stages i, ii and iii for oogenesis and i, ii, iii and iv for spermatogenesis. no embryos or planulae were observed in the histological sections. the gametes or planulae spawning may occur between april and may.
Parental care behavior in the Guiana dolphin, Sotalia guianensis (Cetacea: Delphinidae), in Ilha Grande Bay, southeastern Brazil  [cached]
Rodrigo H. O. Tardin,Mariana A. Espécie,Liliane Lodi,Sheila M. Sim?o
Zoologia (Curitiba) , 2013,
Abstract: Parental care is any form of parental behavior that increases offspring fitness. To the authors' knowledge, this study is the first to analyze the intensity of parental care in the Guiana dolphin, Sotalia guianensis (van Bénéden, 1864). The objectives of this study are as follows: 1) to quantify the degree of parental care in S. guianensis in Ilha Grande Bay, Rio de Janeiro; 2) to investigate the influence of behavioral state and group size on the degree of parental care; and 3) to evaluate the differences between the intensity of parental care provided to calves and juveniles. Our results indicate that the intensity of parental care is high in S. guianensis and that care is more intense in larger groups. It is possible that these differences serve to maximize hydrodynamic gains and to minimize risks. Our results suggest that parental care is more intense during travel. A possible reason for this greater intensity is that the feeding dynamics show a more random pattern than other behavioral states. Moreover, the results indicate that calves receive more intense care than juveniles. These results suggest that parent-offspring conflict is possible in the study population.
Floral Diversity Of Mangrove Forest In The Kaliuntu Bay- Rembang Based On Palynological Evidences
SRI WIDODO AGUNG SUEDY,TRI RETNANINGSIH SOEPROBOWATI,A. TJIPTO RAHARDJO,KHOIRIL ANWAR MARYUNANI
Biodiversitas , 2006,
Abstract: Palynological evidences (polen and spores) have been used to study mangrove diversity of coastal zone sites at Kaliuntu bay (Rembang), province of Central Java. Data was collected in April 2nd to April 17th 2005, following transect method. In this research for sediments sampling used surface-subsurface sampling method (depth in 10cm). The result showed that mangrove forest in the coastal zone of Kaliuntu bay (Rembang) was dominated by Rhizophoarceae polen type (included Rhizophora genera)
Superficial distribution of aromatic compounds and geomicrobiology of sediments from Suruí Mangrove, Guanabara Bay, RJ, Brazil
Fontana, Luiz F.;Silva, Frederico S. da;Figueiredo, Natália G. de;Brum, Daniel M.;Netto, Annibal D. Pereira;Gigueiredo Junior, Alberto G. de;Crapez, Mirian A.C.;
Anais da Academia Brasileira de Ciências , 2010, DOI: 10.1590/S0001-37652010000400022
Abstract: the distribution of selected aromatic compounds and microbiology were assessed in superficial sediments from suruí mangrove, guanabara bay. samples were collected at 23 stations, and particle size, organic matter, aromatic compounds, microbiology activity, biopolymers, and topography were determined. the concentration of aromatic compounds was distributed in patches over the entire mangrove, and their highest total concentration was determinated in the mangrove's central area. particle size differed from most mangroves in that suruí mangrove has chernies on the edges and in front of the mangrove, and sand across the whole surface, which hampers the relationship between particle size and hydrocarbons. an average @ 10% p/p of organic matter was obtained, and biopolymers presented high concentrations, especially in the central and back areas of the mangrove. the biopolymers were distributed in high concentrations. the presence of fine sediments is an important factor in hydrocarbon accumulation. with high concentration of organic matter and biopolymers, and the topography with chernies and roots protecting the mangrove, calmer areas are created with the deposition of material transported by wave action. compared to global distributions, concentrations of aromatic compounds in suruí mangrove may be classified from moderate to high, showing that the studied area is highly impacted.
Chemical and microbiological characterization of mangrove sediments after a large oil-spill in Guanabara Bay - RJ - Brazil
Maciel-Souza, Maria do Carmo;Macrae, Andrew;Volpon, Antonia Garcia Torres;Ferreira, Patrícia Silva;Mendon?a-Hagler, Leda Cristina;
Brazilian Journal of Microbiology , 2006, DOI: 10.1590/S1517-83822006000300013
Abstract: seventeen months after a 1,3 million l oil spill into guanabara bay, analyses of mangrove sediments showed that the three sites closest to the spill remain highly polluted (>10 μg-g-1 polyaromatic hydrocarbons). a fourth site was less polluted, from which most hydrocarbon degrading bacteria were isolated.
Trace metal contamination in mangrove sediments, Guanabara Bay, Rio de Janeiro, Brazil
Farias, Cassia O.;Hamacher, Claudia;Wagener, Angela de Luca R.;Campos, Reinaldo C. de;Godoy, José M.;
Journal of the Brazilian Chemical Society , 2007, DOI: 10.1590/S0103-50532007000600014
Abstract: the guanabara bay in rio de janeiro has undergone profound alterations of its natural environmental conditions. metal concentration increase in sediments has been reported to be among these alterations. trace-metal contamination and availability were studied in sediments of 3 mangrove areas of the bay. cd, zn, pb, ni, cu and al concentrations were determined in segments of sediment cores, after treatment with 1 mol l-1 hcl and with concentrated hno3. fe and mn were determined in the leach with hno3. concentrations were low in comparison to those reported for guanabara bay and cd showed up to 90% recovery in the hcl extract. sediments found to be oxic to suboxic showed avs concentrations in range of 0.07 (bottom) to 18.79 mmol g-1(sub-surface) indicating heterogeneity and apparent disequilibrium. fe and mn oxides, carbonates and organic matter may be the most important phases controlling metal availability and distribution.
Temporal and spatial variations in the structure of macroalgal communities associated with mangrove trees of Ilha do Cardoso, S?o Paulo state, Brazil
YOKOYA, NAIR S.;PLASTINO, ESTELA M.;BRAGA, MARIA DO ROSáRIO A.;FUJII, MUTUE T.;CORDEIRO-MARINO, MARILZA;ESTON, VERENA R.;HARARI, JOSEPH;
Brazilian Journal of Botany , 1999, DOI: 10.1590/S0100-84041999000200010
Abstract: temporal and spatial variations in species composition and vertical distribution of macroalgal communities growing on mangrove trees were analyzed bimonthly in the ilha do cardoso state park, s?o paulo state (25°03's and 47°55'w), southeastern brazil. the macroalgal communities from mangroves of perequê and sítio grande rivers comprised 10 and 18 taxa respectively. bostrychia radicans (mont.) mont. and b. calliptera (mont.) mont. were the predominant taxa, present almost throughout the year and in all the sites studied. the species composition of macroalgal communities from both mangroves presented temporal and spatial variations related to environmental factors. the highest number of taxa was observed during colder, drier months, coinciding with the highest means of high water neap and short periods of continuous emersion (april to august). some mangrove algae such as b. calliptera, rhizoclonium spp., caloglossa spp., and boodleopsis pusilla (collins) w. taylor, joly et bernatowicz showed a high degree of tolerance to desiccation, being able to tolerate continuous emersion up to six days. the spatial variations in species composition were related to light, as observed in catenella caespitosa (withering) l. irvine, which occurred in well-lit sites. no pattern of vertical zonation was observed, since rhizoclonium spp., b. radicans, and b. calliptera occur over the entire vertical range. variations in the range of vertical distribution of macroalgae of perequê mangrove were mainly related to the variations in the tidal levels (mean high water neap and/or mean high water spring) while those observed in sítio grande mangrove were related to salinity variations, except for b. calliptera and caloglossa spp. related to tidal levels and high irradiance, respectively.
Temporal and spatial variations in the structure of macroalgal communities associated with mangrove trees of Ilha do Cardoso, S o Paulo state, Brazil
YOKOYA NAIR S.,PLASTINO ESTELA M.,BRAGA MARIA DO ROSáRIO A.,FUJII MUTUE T.
Brazilian Journal of Botany , 1999,
Abstract: Temporal and spatial variations in species composition and vertical distribution of macroalgal communities growing on mangrove trees were analyzed bimonthly in the Ilha do Cardoso State Park, S o Paulo state (25°03'S and 47°55'W), Southeastern Brazil. The macroalgal communities from mangroves of Perequê and Sítio Grande rivers comprised 10 and 18 taxa respectively. Bostrychia radicans (Mont.) Mont. and B. calliptera (Mont.) Mont. were the predominant taxa, present almost throughout the year and in all the sites studied. The species composition of macroalgal communities from both mangroves presented temporal and spatial variations related to environmental factors. The highest number of taxa was observed during colder, drier months, coinciding with the highest means of high water neap and short periods of continuous emersion (April to August). Some mangrove algae such as B. calliptera, Rhizoclonium spp., Caloglossa spp., and Boodleopsis pusilla (Collins) W. Taylor, Joly et Bernatowicz showed a high degree of tolerance to desiccation, being able to tolerate continuous emersion up to six days. The spatial variations in species composition were related to light, as observed in Catenella caespitosa (Withering) L. Irvine, which occurred in well-lit sites. No pattern of vertical zonation was observed, since Rhizoclonium spp., B. radicans, and B. calliptera occur over the entire vertical range. Variations in the range of vertical distribution of macroalgae of Perequê mangrove were mainly related to the variations in the tidal levels (mean high water neap and/or mean high water spring) while those observed in Sítio Grande mangrove were related to salinity variations, except for B. calliptera and Caloglossa spp. related to tidal levels and high irradiance, respectively.
Mangrove bird community of Paranaguá Bay - Paraná, Brazil
Mestre, Luiz Augusto Macedo;Krul, Ricardo;Moraes, Valéria dos Santos;
Brazilian Archives of Biology and Technology , 2007, DOI: 10.1590/S1516-89132007000100009
Abstract: this study describes the mangrove bird community of paranaguá bay in paraná - south brazil. seasonal surveys were conducted during september 1997 to september 1998 at three sites in paranaguá bay. frequencies and abundances of birds were registered in 200m transects and one hour point counts. a total of 81 bird species were observed in the three sampling sites. most of the bird species in paranaguá mangroves are fruits, seeds and arthropods consumers, and predators of flying insects. the most frequent and abundant species were egretta caerulea, ceryle torquata, chloroceryle amazona, pitangus sulphuratus, turdus amaurochalinus and parula pitiayumi. the bird community of these three sites is composed mainly by forest bird species. the mangroves of paranaguá bay shelter one of the richest avifauna of brazilian mangroves. differences between sampling sites could be related to the proximity of the paranaguá city and human impacts in the areas. only in the most disturbed site were observed passer domesticus and large flocks of coragyps atratus. this study contributed to the knowledge of mangrove communities, and could be an important basis to fluvial-marine conservation plans in paraná- brazil.
Primary carbon sources for juvenile penaeid shrimps in a mangrove-fringed bay of Inhaca island, Mozambique
A Macia
Western Indian Ocean Journal of Marine Science , 2004,
Abstract: A study to estimate the relative importance of mangrove primary carbon and nitrogen sources to five commercial penaeid shrimps species was done at Saco da Inhaca, a non-estuarine mangrove-fringed bay on Inhaca Island, southern Mozambique. Carbon and nitrogen stable isotope ratios were determined in a variety of primary producers (mangroves, epiphytes, phytoplankton and seagrasses), sediments and in five penaeid shrimp species (Penaeus (Fenneropenaeus) indicus, P. japonicus, P. semisulcatus, Metapenaeus monoceros and M. stebbingi), collected within the bay in different habitats and during two different periods. The penaeid shrimps showed 13C values ranging from –13 to –19 ‰, (average of –15.6 ± 0.4 ‰, n=19) which is highly enriched compared to the mean value for mangrove leaves (average - 27.6± 3.6 ‰, n=3) which varied from –20 to –32‰. The results shows that some shrimps may derive their carbon either from detritus, plankton remains or from benthic organisms. Overall, the carbon isotopic signal shifted as the shrimps got bigger, suggesting a change of diet with growth. No significant differences were found between 15N isotope values among the shrimps studied, indicating that they may belong in the same trophic position (except P. semisulcatus, which occupies a higher level). There is some evidence that sampling period influences the carbon isotope ratios for sediment and shrimps.
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