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65 resultados encontrados para: AUTOR: Hernández Arana, Héctor Abuid
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1.
- Artículo con arbitraje
*En hemeroteca, SIBE-San Cristóbal
Drivers of mangrove litterfall within a karstic region affected by frequent hurricanes
Adame, María F. ; Zaldívar Jiménez, Arturo (coaut.) ; Teutli, Claudia (coaut.) ; Caamal, Juan P. (coaut.) ; Anduez, María T. (coaut.) ; López Adame, Haydée (coaut.) ; Cano, Romel (coaut.) ; Hernández Arana, Héctor Abuid (coaut.) ; Torres Lara, Ricardo (coaut.) ; Herrera Silveira, Jorge Alfredo (coaut.) ;
Contenido en: Biotropica Vol. 45, no. 2 (March 2013), p. 147–154 ISSN: 0006-3606
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
35840-20 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Inglés |
Resumen en inglés

Tropical storms can shape the structure and productivity of mangrove forests. In this study, we compared current litterfall with historical tropical storm disturbance in the karstic Yucatan Peninsula (YP). We also explored the relationship between litterfall and the fresh/seawater mixture of floodwater. Our hypotheses were that litterfall peaks at moderate perturbations and in sites where seawater dominates the floodwater mixture, and thus, where soil total phosphorus (TP) is relatively high. Litterfall was sampled for 2 yr, from eight mangrove forests around the YP. At each site, forest structure, interstitial salinity, TP, nitrogen, carbon, pH, and bulk density were measured. Our results show that mangrove forest from northeast YP are historically impacted by stronger and more frequent tropical storms compared with those in northwest and southeast YP, where tropical storm intensity is moderate and mild, respectively. Litterfall was higher in northwest YP ( 3 g/m2 d) compared with northeast and southeast ( 2 g/m2 d), mimicking a subsidy-stress gradient where highest productivity is reached at moderate perturbations. Neither salinity nor forest structure alone satisfactorily explained litterfall variability. Soil TP followed a similar geographical pattern as the disturbance gradient: highest concentrations in the northwest YP ( 0.05%) and lowest in the northeast and southeast ( 0.03%). Thus, it is likely that TP, and not tropical storm disturbance, is the main driver of litterfall in mangrove forests of the YP. Alterations in TP availability (e.g., sea level rise and aquifer contamination) have the potential to modify mangrove productivity in the region.


2.
Tesis - Doctorado
PDF
Índice | Resumen en: Español |
Resumen en español

Se presenta una reconstrucción paleoambiental del Holoceno medio y tardío a través del análisis de sedimentos de manglar obtenidos en la desembocadura del Río Hondo, al sur de la Península de Yucatán. El Polen fósil y los análisis de elementos geoquímicos permitieron reconstruir cambios paleoecológicos y paleoclimáticos de los últimos 5,600 años, donde se encontraron variaciones ecológicas, de precipitación y escorrentía relacionadas con eventos climáticos globales. Durante el Holoceno medio hasta alrededor de 4,000 años antes del presente (AP), los cambios en la vegetación muestran haber estado más influenciados por patrones oceánico-atmosféricos originados en el océano Atlántico. Los indicadores geoquímicos mostraron los mayores niveles de precipitación, resultados que corresponden con la posición hacia el norte de la Zona de Convergencia Inter-tropical. Los cambios en la dinámica de los sistemas de manglar fue limitada, principalmente, por el aumento del nivel del mar. A partir de 4,000 AP, el incremento de la actividad ENSO, al oriente del Océano Pacífico, se hace evidente a través de cambios en la dinámica de la vegetación. Las selvas subperennifolias y las selvas secas se expanden en respuesta a la progresiva reducción de la precipitación. Los sistemas de manglar aumentaron su cobertura debido a la relentización en el aumento del nivel del mar durante este tiempo. Los cambios en la precipitación coinciden con un efecto acoplado de cambios en la posición de la Zona de Convergencia Inter-tropical y el aumento de la actividad ENSO.

Hacia 2,600 AP se registra el mínimo de precipitación en toda la temporalidad del estudio. Posteriormente las condiciones ambientales fueron favorables para la expansión de selvas hasta 2,000 AP, cuando se registra intensa actividad ENSO. El registro polínico sugiere una diversificación de los tipos de selva en respuesta a este forzamiento. La cobertura de los sistemas de manglar aumentó y el mangle botoncillo (Conocarpus erectus) fue la especie mejor representada. El establecimiento de los actuales sistemas de manglar rojo achaparrado fue a partir de la estabilización del nivel del mar, entre 3,600 y 4,000 AP, aunque la presencia de manglar fue desde el Holoceno medio. Los abruptos cambios en la vegetación e indicadores geoquímicos durante los últimos 2,000 años pueden estar relacionados con la intensa actividad ENSO. 2 Por otra parte, las actividades humanas fueron registradas desde el Holoceno medio. Sin embargo, los procesos de cambio en la vegetación fueron principalmente en respuesta a forzamientos climáticos basados en la composición del espectro polínico fósil. Finalmente, existen registros de eventos paleoclimáticos a escala global hace 5,200, 4,200 y 2,600 años, sin embargo, resulta necesario aumentar el número de sitios de estudio y obtener un mayor número de datos para realizar análisis numéricos y encontrar alguna ciclicidad en los procesos de cambio climático encontrados.

Índice

Resumen
Capítulo I: Introducción y objetivos
Capítulo II: Climate forcings on vegetation of the southeastern Yucatán Peninsula (Mexico) during the middle to late Holocene
Capítulo III: Middle and late Holocene mangrove dynamics of the Yucatan Peninsula, Mexico
Capítulo IV: Conclusiones generales
Literatura citada


3.
Tesis - Maestría
Complejidad estructural a escalas espaciales finas de un parche arrecifal impactado por encallamiento en Punta Cancún, Quintana Roo, México / Elizabeth Arista de la Rosa
Arista de la Rosa, Elizabeth ; Hernández Arana, Héctor Abuid (tutor) ; Espinoza Ávalos, Julio (asesor) ; Ruíz Zárate, Miguel Ángel (asesor) ; Vega Zepeda, Alejandro (asesor) ;
Chetumal, Quintana Roo, México : El Colegio de la Frontera Sur , 2013
Clasificación: TE/577.789097267 / A7
Cerrar
SIBE Campeche
ECO040005246 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
ECO030007924 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010017497 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Tapachula
ECO020012711 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Villahermosa
ECO050005546 (Disponible)
Disponibles para prestamo: 1
PDF
Índice | Resumen en: Español |
Resumen en español

La pérdida de cobertura coralina reportada para el Mar Caribe en las últimas décadas ha resultado en una pérdida en complejidad estructural; atributo físico que facilita diversos procesos ecológicos determinantes para la estructura comunitaria, y es particularmente sensible a disturbios físicos, como encallamientos. Diversos estudios de disturbio en arrecifes coralinos se realizan a una escala espacial amplia, con lo que se pueden perder patrones estructurales que ocurren a escalas finas e indiquen la recuperación del hábitat. En el presente estudio se evaluó la complejidad estructural de un parche arrecifal impactado por encallamiento en 1997, al Norte de Quintana Roo. Como un subrogado de la complejidad, se obtuvo un índice de rugosidad del sustrato en tres escalas espaciales finas, bimensualmente durante un año. Para probar la hipótesis de que la complejidad estructural es un atributo determinado por la dinámica de la comunidad, composición y permanencia de los grupos bénticos estructurales, así como por la escala espacial a la que sea evaluada. Dado el tiempo transcurrido desde el encallamiento, se esperaba observar patrones estructurales que dieran indicios de recuperación.

Los resultados mostraron diferencias en rugosidad al ampliarse la resolución de observación. En la zona de impacto, el grupo estructural asociado a las diferencias estructurales fue de las esponjas mientras que el sitio de referencia estuvo asociado a algas costrosas coralinas y corales masivos, principalmente Porites astreoides. Respecto a los meses, Octubre fue el único en presentar diferencias, determinadas por la presencia de macroalgas carnosas. La composición diferencial sugiere distintas etapas de sucesión en las dos zonas, sin embargo, la presencia de especies oportunistas en ambos sitios podría ser un resultado de los distintos disturbios a los que el parche ha sido sujeto, independientemente del encallamiento y pese a los esfuerzos de manejo que se han realizado en el área.

Índice

Introducción
Artículo: Structural complexity at fine spatial scales in a ship grounded patch reef in Quintana Roo, Mexico
Abstract
Introduction
Materials and methods
Study area
Sampling design
Statistical analyses
Results
Discussion
Acknowledgements
References
Figures
Tables
Conclusiones
Literatura citada


4.
- Artículo con arbitraje
PDF
Resumen en: Inglés |
Resumen en inglés

The arrival of large masses of drifting Sargassum since 2011 has caused changes in the natural dynamics of Caribbean coastal ecosystems. In the summer of 2015, unprecedented and massive mats of S. fluitans and S. natans have been observed throughout the Mexican Caribbean including exceptional accumulations ashore. This study uses stable isotopes to assess the impact of Sargassum blooms on the trophic dynamics of the Diadema antillarum sea urchin, a keystone herbivore on many Caribbean reefs. Bayesian models were used to estimate the variations in the relative proportions of carbon and nitrogen of assimilated algal resources. At three lagoon reef sites, the niche breadth of D. antillarum was analysed and compared under massive influx of drifting Sargassum spp. vs. no influx of Sargassum blooms. The effects of the leachates generated by the decomposition of Sargassum led to hypoxic conditions on these reefs and reduced the taxonomic diversity of macroalgal food sources available to D. antillarum. Our trophic data support the hypothesis that processes of assimilation of carbon and nitrogen were modified under Sargassum effect. Isotopic signatures of macroalgae associated with the reef sites exhibited significantly lower values of 15N altering the natural herbivory of D. antillarum. The Stable Isotopes Analysis in R (SIAR) indicated that, under the influence of Sargassum blooms, certain algal resources (Dictyota, Halimeda and Udotea) were more assimilated due to a reduction in available algal resources. Despite being an abundant available resource, pelagic Sargassum was a negligible contributor to sea urchin diet.

The Stable Isotope Bayesian Ellipses in R (SIBER) analysis displayed differences between sites, and suggests a reduction in trophic niche breadth, particularly in a protected reef lagoon. Our findings reveal that Sargassum blooms caused changes in trophic characteristics of D. antillarum with a negative impact by hypoxic conditions. These dynamics, coupled with the increase in organic matter in an oligotrophic system could lead to reduce coral reef ecosystem function.


Resumen en: Inglés |
Resumen en inglés

Mexico harbors more than 10% of the planet’s endemic species. However, the integrity and biodiversity of many ecosystems is experiencing rapid transformation under the influence of a wide array of human and natural disturbances. In order to disentangle the effects of human and natural disturbance regimes at different spatial and temporal scales, we selected six terrestrial (temperate montane forests, montane cloud forests, tropical rain forests, tropical semi-deciduous forests, tropical dry forests, and deserts) and four aquatic (coral reefs, mangrove forests, kelp forests and saline lakes) ecosystems. We used semi-quantitative statistical methods to assess (1) the most important agents of disturbance affecting the ecosystems, (2) the vulnerability of each ecosystem to anthropogenic and natural disturbance, and (3) the differences in ecosystem disturbance regimes and their resilience. Our analysis indicates a significant variation in ecological responses, recovery capacity, and resilience among ecosystems. The constant and widespread presence of human impacts on both terrestrial and aquatic ecosystems is reflected either in reduced area coverage for most systems, or reduced productivity and biodiversity, particularly in the case of fragile ecosystems (e.g., rain forests, coral reefs). In all cases, the interaction between historical human impacts and episodic high intensity natural disturbance (e.g., hurricanes, fires) has triggered a reduction in species diversity and induced significant changes in habitat distribution or species dominance. The lack of monitoring programs assessing before/after effects of major disturbances in Mexico is one of the major limitations to quantifying the commonalities and differences of disturbance effects on ecosystem properties.


6.
- Artículo con arbitraje
Distribution and abundance of the Central American river turtle, Dermatemys Mawii, in southern Quintana Roo, Mexico: implications for a regional conservation strategy
Calderón Mandujano, Romel René ; Hernández Arana, Héctor Abuid (coaut.) ; Flores Villela, Oscar Alberto (coaut.) ;
Contenido en: Journal of Biodiversity & Endangered Species Vol. 5, no. 3, 1000198 (September 2017), p. 1-6 ISSN: 2332-2543
PDF
Resumen en: Inglés |
Resumen en inglés

We estimated the distribution and abundance of the Central American River Turtle, Dermatemys mawii, in four aquatic systems in southern Quintana Roo, Mexico. Using nets and free diving we captured 52 individuals D. mawii among the winter, dry and rainy seasons. We recorded 12 variables to characterize the habitat and correlated these with the abundance of D. mawii. Using catching per unit effort, we evaluated the species’ relative abundance for each aquatic system. Using Maxent, we modeled the potential distribution of D. mawii using historical and present locality data. We recorded 81 D. mawii individuals using systematic sampling and casual observations. La Union was the site with the highest relative abundance (~4 ind.-net). We found a negative correlation between D. mawii abundance and salinity. The model of potential distribution identified sites with ecological conditions suitable for the species where it is undocumented. Information about the ecology of this species remains scarce, but we propose that identifying management units could improve conservation of the species at local and regional levels.


7.
Capítulo de libro - Memoria en extenso
*Solicítelo con su bibliotecario/a
Descomposición de hojarasca de manglar en la Isla de Tamalcab, Quintana Roo
Canul Ramírez, Elda Aurora ; Hernández Arana, Héctor Abuid (coaut.) ; López Adame, Haydée (coaut.) ;
Contenido en: Memorias: segundo congreso mexicano de ecosistemas de manglar: hacia el aprendizaje continuo y el manejo integral Ciudad del Carmen, Campeche, México : Universidad Autónoma del Carmen, Centro de Investigación de Ciencias Ambientales, 2012 p. 174-175
Nota: Solicítelo con su bibliotecario/a

8.
- Artículo con arbitraje
Inferring spatial and temporal behavioral patterns of free-ranging manatees using saltwater sensors of telemetry tags
Castelblanco Martínez, Delma Nataly ; Morales Vela, José Benjamín (coaut.) ; Slone, Daniel H. (coaut.) ; Padilla Saldívar, Janneth A. (coaut.) (1971) ; Reid, James P. (coaut.) ; Hernández Arana, Héctor Abuid (coaut.) ;
Contenido en: Mammalian Biology - Zeitschrift für Säugetierkunde Vol. 80, no. 1 (January 2015), p. 21-30 ISSN: 1616-5047
Resumen en: Inglés |
Resumen en inglés

Diving or respiratory behavior in aquatic mammals can be used as indicator of physiological activity and consequently, to infer behavioral patterns. Five Antillean manatees, Trichechus manatus manatus, were captured in Chetumal Bay and tagged with GPS tracking devices. The radios were equipped with a micropower saltwater sensor (SWS), which records the times when the tag assembly was submerged. The information was analyzed to establish individual fine-scale behaviors. For each fix, we established the following variables: Distance (D), sampling interval (T), movement rate (D/T), number of dives (N), and total diving duration (TDD). We used logic criteria and simple scatterplots to distinguish between behavioral categories: ‘Travelling’ (D/T≥3 km/h), ‘Surface’ (↓TDD,↓N), ‘Bottom feeding’ (↑TDD,↑N) and ‘Bottom resting’ (↑TDD,↓N). Habitat categories were qualitatively assigned: Lagoon, Channels, Caye shore, City shore, Chanel edge, and Open areas. The instrumented individuals showed a daily rhythm of bottom activities, with surfacing activities more frequent during the night and early in the morning. More investigation into those cycles and other individual fine-scale behaviors related to their proximity to concentrations of human activity would be informative.


9.
- Artículo con arbitraje
PDF
Resumen en: Inglés |
Resumen en inglés

Information from 15 satellite-tracked Antillean manatees (Trichechus manatus manatus) was analyzed in order to assess individual movements, home ranges, and high-use areas for conservation decisions. Manatees were captured in Chetumal Bay, Mexico, and tagged with Argos-monitored satellite transmitters. Location of the manatees and physical characteristics were assessed to describe habitat properties. Most manatees traveled to freshwater sources. The Maximum Area Size (MAS) for each manatee was determined using the observation- area method. Additional kernel densities of 95% home range and 50% Center of Activity (COA) were also calculated, with manatees having 1–3 COAs. Manatees exhibited two different movement patterns: remaining in Chetumal Bay, and long-distance (up to 240 km in 89 d). The residence time in Chetumal Bay was higher for females (89.6% of time) than for males (72.0%), but the daily travel rate (0.4–0.5 km/d) was similar for both sexes. Most of the COAs fell within Natural Protected Areas (NPA). However, manatees also travel for long distances into unprotected areas, where they face uncontrolled boat traffic, fishing activities, and habitat loss. Conservation of movement corridors may promote long-distance movements and facilitate genetic exchange.


10.
- Artículo con arbitraje
Resumen en: Inglés |
Resumen en inglés

Chetumal Bay is a refuge for the manatee, Trichechus manatus, a large and strictly herbivorous aquatic mammal. The ecosystem is notoriously poor in subaquatic vegetation, the main components of manatees’ diet. Due to the constant presence of manatees in the bay and their ability to consume large volumes of plant material, it is assumed that the species has a relevant trophic impact on the system. A mass–balance trophic model was designed to describe the flows of energy and matter in the bay, with the goal of assessing the role of manatees in the system. The system was aggregated in eight effective trophic levels. The biomass was intensely concentrated in the detritus, suggesting that the matter on the bottom sediment is the main regulator of the energy flow in the system. Primary producers comprised of detritus, mangrove, benthic autotrophs, and phytoplankton. The apex predators were dolphins and large piscivorous fishes. Manatees occupied the trophic level 2.0. Manatees were directly or indirectly impacted by autotrophs, mangrove, and detritus; but the competition between manatees and other groups was insignificant. In comparison to other ecosystems where manatees occur, Chetumal Bay (BCh) has the lowest relative biomass of seagrasses. Several ecological and behavioral mechanisms to compensate the lack of macrophytes biomass (or a combination of several) are suggested. Ecopath with Ecosim models are useful to describe the flow of energy and matter in the ecosystems. However, there are still critical gaps in the knowledge of BCh and its manatee population. It is difficult to assess the uncertainty associated with the estimates obtained; therefore, results should be interpreted with caution. Improving this preliminary model with robust local information on the Chetumal Bay ecology and its manatee population is recommended.