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6 resultados encontrados para: AUTOR: Aguirre Macedo, María Leopoldina
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1.
Artículo
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Resumen en: Inglés |
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The oceanographic conditions of the Pacific Ocean are largely modified by El Niño (EN), affecting several ecological processes. Parasites and other marine organisms respond to environmental variation, but the influence of the EN cycle on the seasonal variation of parasitic copepods has not been yet evaluated. We analysed the relation between infection parameters (prevalence and mean intensity) of the widespread parasitic copepods Caligus bonito and Charopinopsis quaternia in the dolphinfish Coryphaena hippurus and oceanography during the strong 2015–16 EN. Fish were collected from capture fisheries on the Ecuadorian coast (Tropical Eastern Pacific) over a 2-year period. Variations of sea surface temperature (SST), salinity, chlorophyll a (Chl-a), Oceanic Niño Index (ONI), total host length (TL) and monthly infection parameters of both copepod species were analysed using time series and cross-correlations.

We used the generalised additive models for determine the relationship between environmental variables and infection parameters. The total body length of the ovigerous females and the length of the eggs of C. bonito were measured in both periods. Infection parameters of both C. bonito and Ch. quaternia showed seasonal and annual patterns associated with the variation of environmental variables examined (SST, salinity, Chl-a and ONI 1+2). Infection parameters of both copepod species were significantly correlated with ONI 1+2, SST, TL and Chl-a throughout the GAMLSS model, and the explained deviance contribution ranged from 16%-36%. Our results suggest than an anomaly higher than +0.5°C triggers a risen in infection parameters of both parasitic copepods. This risen could be related to increases in egg length, female numbers and the total length of the ovigerous females in EN period. This study provides the first evidence showing that tropical parasitic copepods are sensitive to the influence of EN event, especially from SST variations. The observed behaviour of parasitic copepods likely affects the host populations and structure of the marine ecosystem at different scales.


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The southern Gulf of Mexico (sGoM) is highly susceptible to receiving environmental impacts due to the recent increase in oil-related activities. In this study, we assessed the changes in the bacterioplankton community structure caused by a simulated oil spill at mesocosms scale. The 16S rRNA gene sequencing analysis indicated that the initial bacterial community was mainly represented by Gamma-proteobacteria, Alpha-proteobacteria, Flavobacteriia, and Cyanobacteria. The hydrocarbon degradation activity, measured as the number of culturable hydrocarbonoclastic bacteria (CHB) and by the copy number of the alkB gene, was relatively low at the beginning of the experiment. However, after four days, the hydrocarbonoclastic activity reached its maximum values and was accompanied by increases in the relative abundance of the well-known hydrocarbonoclastic Alteromonas. At the end of the experiment, the diversity was restored to similar values as those observed in the initial time, although the community structure and composition were clearly di erent, where Marivita, Pseudohongiella, and Oleibacter were detected to have di erential abundances on days eight–14. These changes were related with total nitrogen (p value = 0.030 and r² = 0.22) and polycyclic aromatic hydrocarbons (p value = 0.048 and r² = 0.25), according to PERMANOVA. The results of this study contribute to the understanding of the potential response of the bacterioplankton from sGoM to crude oil spills.


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Background: We assessed metrics of the metazoan parasite infracommunities of the dusky founder (Syacium papillosum) as indicators of aquatic environmental health of the Yucatan Shelf (YS) prior to oil extraction. We sampled the dusky founder and its parasites along the YS, mostly during the 2015 north wind season (November–April). Our aims were: (i) to determine whether the parasite infracommunity metrics of S. papillosum exhibit signifcant diferences among YS subregions; (ii) to determine whether the probability of the occurrence of its parasite species and individu‑ als were afected by environmental variables, nutrients, heavy metals and hydrocarbons at the seascape level; and (iii) to determine whether there were statistical diferences between the parasite infracommunity metrics of S. papillosum from YS and those of Syacium gunteri from the Campeche Sound. Multivariate statistical analyses and generalised additive models (GAMs) were used to examine the potential statistical associations between the contaminants, environmental variables and parasite community metrics, and the maximum entropy algorithm (MaxEnt) was used to characterise the habitat’s suitability for the parasite’s probability of occurrence. Results: We recovered 48 metazoan parasite species from 127 S. papillosum, with larval cestodes and digeneans being the most numerically-dominant. Multivariate analyses showed signifcant diferences in parasite infracommu‑ nity metrics among Western YS, Mid YS and Caribbean subregions, with the latter being the richest in species but not in individuals. The GAM and MaxEnt results indicated a negative efect of top predators (e.g. sharks and rays) removal on parasite metrics. The parasite infracommunities of S. papillosum were twice as rich in the number of species and individuals as those reported for S. gunteri from the Campeche Sound.

Conclusions: The significant differences among subregions in parasite metrics were apparently due to the interruption of the Yucatan current during the north wind season. The fishing of top predators in combination with an influx of nutrients and hydrocarbons in low concentrations coincides with an increase in larval cestodes and digeneans in S. papillosum. The dusky founder inhabits a region (YS) with a larger number of metazoan parasite species compared with those available for S. gunteri in the Campeche Sound, suggesting better environmental conditions for transmis‑ sion in the YS.


4.
Artículo
*En hemeroteca, SIBE-Chetumal
Water quality variability and eutrophic trends in karstic tropical coastal lagoons of the Yucatan Peninsula
Tapia González, Fedro Uriel (autor) ; Herrera Silveira, Jorge Alfredo (autor) ; Aguirre Macedo, María Leopoldina (autora) ;
Contenido en: Estuarine Coastal and Shelf Science Vol. 76, no. 2 (2008), p. 418-430 ISSN: 0272-7714
Bibliotecas: Chetumal
Cerrar
SIBE Chetumal
44715-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-Chetumal

5.
Artículo
*En hemeroteca, SIBE-Chetumal
Parasite survey of the eastern oyster Crassostrea virginica in coastal lagoons of the southern Gulf of Mexico
Aguirre Macedo, María Leopoldina (autora) ; Simá Álvarez, Raúl A. (autor) ; Román Magaña, María Karla (autora) ; Güemez Ricalde, Jorge I. (autor) ;
Contenido en: Journal of Aquatic Animal Health Vol. 19, no. 4 (diciembre 2007), p. 270-279 ISSN: 0899-7659
Bibliotecas: Chetumal
Cerrar
SIBE Chetumal
60630-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-Chetumal

6.
Libro
Contribuciones de la ciencia al manejo costero integrado de la Bahía de Chetumal y su área de influencia / por: Francisco J. Rosado May, Rafael Romero Mayo y Alberto de Jesús Navarrete, (editores)
Encuentro Internacional sobre la Bahía de Chetumal y su Área de Influencia (2001) ; Rosado May, Francisco Javier (editor) ; Romero Mayo, Rafael Ignacio (editor) ; De Jesús Navarrete, Alberto (editor) ;
Chetumal, Quintana Roo, México : Universidad de Quintana Roo. Programa de Manejo Integrado de Recursos Costeros , 2002
Clasificación: Q/333.917160972 / E5/2
Bibliotecas: Chetumal , San Cristóbal
Cerrar
SIBE Chetumal
ECO030001001 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010005496 (Disponible)
Disponibles para prestamo: 1