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50 resultados encontrados para: AUTOR: Quintana Ascencio, Pedro F
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1.
Artículo
Lluvia de semillas y establecimiento en comunidades sucesionales en Chiapas, México
Carrillo Arreola, Fernando (autor) ; Quintana Ascencio, Pedro F. (autor) (1959-) ; Ramírez Marcial, Neptalí (autor) (1963-) ; González Espinosa, Mario (autor) (1950-) ;
Disponible en línea
Contenido en: Acta Botanica Mexicana Número 127, e1618 (2020), p. 1-28 ISSN: 2448-7589
PDF
Resumen en: Español | Inglés |
Resumen en español

Antecedentes y Objetivos: La agricultura en los trópicos reduce, fragmenta y altera los bosques y los paisajes forestales. Evaluamos la riqueza de especies y la dominancia de formas de vida en la lluvia de semillas, y la abundancia y supervivencia anual de nuevos reclutas en bosques maduros, medianamente maduros, bosques tempranos, potreros y campos de cultivo en ambientes naturales y humanizados. Pronosticamos diferencias en composición y número de semillas y de reclutas en función de los diferentes hábitats y de las matrices de vegetación que los circundan. Métodos: Durante un año se colectaron muestras de semillas y plantas en Lacanjá-Chansayab y Bonampak-Bethel, ambas dentro de la zona de amortiguamiento de la Reserva de la Biosfera de Montes Azules, Selva Lacandona, Chiapas, México. Para la lluvia de semillas, instalamos 14 trampas en sitios que representan el gradiente de sucesión en la vegetación local (2 sitios × 6 hábitats × 14 trampas; n = 168). Independientemente, para evaluar los cambios en reclutamiento y supervivencia tempranas se establecieron 15 cuadros (0.5 × 2.0 m) en cada comunidad arbolada (2 sitios × 3 comunidades × 15 cuadros; n = 90).

Resultados clave: Colectamos ~13,600 semillas de 144 especies pertenecientes a 48 familias botánicas. Los bosques maduros presentaron la mayor riqueza (60-61) y los potreros la menor (14-11). Observamos una reducción en la riqueza de especies y un cambio en la dominancia de las formas de vida a través del gradiente sucesional. Los bosques incluyeron principalmente semillas de árboles, mientras los potreros estuvieron dominados por unas pocas especies de gramíneas. La lluvia de semillas en las áreas agrícolas se caracterizó por un reducido número de especies generalistas. Para los reclutas de especies leñosas, se registraron ~3416 individuos (<0.5 m de altura) de 238 morfoespecies, de las cuales 129 fueron identificadas a nivel de especie en 42 familias. El mayor número de reclutas ocurrió en bosques maduros comparados con bosques tempranos y su supervivencia fue mayor en los bosques maduros. Conclusiones: Documentamos la progresiva simplificación y homogenización en la composición florística y el efecto generalizado de los humanos en las regiones tropicales.

Resumen en inglés

Background and Aims: Agriculture in the tropics is decreasing, fragmenting and altering forests and forest landscapes. We hypothesized differences in species richness and dominance of life forms in the seed rain and in richness and survival in the recruit assemblages among mature forests, mid-successional forests, early successional forests, pastures and milpa fields (arable lands with maize) surrounded by natural and human disturbed habitats. Methods: Samples of seeds and plants were collected during a year in Lacanjá-Chansayab and Bonampak-Bethel, in the buffer zone of the Montes Azules Biosphere Reserve, Selva Lacandona, Chiapas, Mexico. We deployed 14 seed traps in 12 sites representing a gradient of vegetation succession (2 sites × 6 habitats × 14 traps; n = 168 traps). Independently, to assess changes in recruitment and early survival, we established 15 quadrats (0.5 × 2.0 m) in each of the studied forests (2 sites × 3 habitats × 15 quadrats; n = 90 quadrats).

Key results: We collected ~13,600 seeds of 144 species from 48 botanical families. Mature forests had the highest seed rain species richness (60-61) and pastures (14-11) the lowest. We observed a decline in species richness and a change in dominance of life forms in the seed rain from less disturbed to most perturbed habitats. Mature forests included seeds of diverse tree species while the assemblage in pastures was dominated by seeds of few grass species. Intensive traditional milpa fields showed homogeneous seed assemblages. For the new recruits, we recorded ~3,416 individuals (<0.5 m height) of 238 morphospecies in 42 families, 129 were identified to species level. The largest number of species occurred in mature and mid-successional stands compared to early forests. Annual survival of recruits was higher in mid- and late successional forests than in early ones. Conclusions: We document species loss and widespread simplification and homogenization in community composition due to pervasive effect of humans on remnant tropical lowland forests.


2.
Artículo
Resumen en: Inglés |
Resumen en inglés

Leaves of the long-lived Dioon merolae have been harvested intensively for decades (possibly for centuries) for ceremonial purposes by Zoque and mestizo groups inhabiting the Central Depression of Chiapas, Mexico. Over a period of four years, we evaluated vital rates (stem growth, leaf production, reproductive performance, and survival) and projected population growth rates in three populations (250 plants each, divided into eight size classes: new germinants, seedlings, saplings (S1, S2), and adults, A1-A4) with different leaf harvesting histories: non-defoliated by humans for at least 55 years (or very old harvest), defoliated annually until 15 years ago (recovering from harvest), and defoliated annually for at least the past 25 years (currently being harvested intensely). Population structure was affected by leaf harvest history. Stem growth was negatively affected by the annual harvest of leaves in size classes from seedlings up to A4 (ANOVA, P < 0.003); fewer leaves were produced by seedlings, saplings and adults at the annually harvested site (ANOVA, P < 0.027). Survival was high at all sites across all size classes; in the annually harvested site, A4 plants showed a decrease in survival (one dead out of four plants). Sex ratio of adults that produced cones during the four years of study was 61% males to 39% females. At the non-defoliated site, adult classes A2 and A4 produced >80% of the cones; no cones were produced by the A3 and A4 adult size classes at the annually harvested site.

Asymptotic estimates of population growth indicated growing populations (λ≥1): the highest mean values of finite population growth rate were obtained in the non-harvested site (λ = 1.0202). Elasticity analysis with population projection matrices indicated that stasis (L, 9-38%) was the component that most contributed to λ, followed by growth (G, 1.2-2.9%), and fecundity (F, 0.2-1.1 %). We observed detrimental effects on several vital rates due to continued long-term defoliation, although population growth parameters do not currently suggest a decreased trend as a result of the annual harvest of leaves. The duration of this study of a very long-lived plant species suggests caution when setting levels and frequency of leaf harvest. The results help pinpoint practical recommendations that could be implemented in a sustainable management plan for this species, particularly to increase seed production in the annually harvested site, and recruitment of new germinants and seedlings at all sites. However, sound practices will need to consider the interests of involved stakeholders (landowners, pilgrims, conservation organizations and authorities) to effectively reduce anthropogenic pressure on this endangered species.


3.
Tesis - Maestría
Efecto del aprovechamiento foliar en Chamaedorea quezalteca (Palmae) en el Triunfo, Chiapas, México / Rubén Martínez Camilo
Martínez Camilo, Rubén ; González Espinosa, Mario (tutor) (1950-) ; Ruiz Montoya, Lorena (asesor) (1964-) ; Quintana Ascencio, Pedro F. (asesor) (1959-) ; Pérez Farrera, Miguel Ángel (asesor) ;
San Cristóbal de Las Casas, Chiapas, México : El Colegio de la Frontera Sur , 2010
Clasificación: TE/633.58097275 / M3
Cerrar
SIBE Campeche
ECO040004249 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
ECO030007279 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010008432 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Tapachula
ECO020011568 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Villahermosa
ECO050004532 (Disponible)
Disponibles para prestamo: 1
PDF
Resumen en: Español |
Resumen en español

Las hojas de la palma Chamaedorea quezalteca son un recurso forestal no maderable importante para las comunidades de la Sierra Madre de Chiapas. Se presentan los resultados obtenidos de un experimento de defoliación artificial de un año de duración sobre las respuestas en producción foliar, mortalidad y reproducción. El estudio se realizó en tres sitios de la Reserva de la Biosfera El Triunfo, Chiapas, México. Se seleccionaron 600 individuos en tres categorías de tamaños definidas por el número de tallos (1-3, 4-6 y >7). Se aplicaron tres tratamientos de defoliación (30, 60 y 100%) y un testigo (0%). Se realizó un análisis de covarianza para un diseño factorial mixto con dos factores fijos (tratamiento y tamaño) y uno aleatorio (sitio) y la cobertura del bosque como covariable. Se registraron ocho individuos muertos y 20% de los individuos perdió uno o más tallos en todo el experimento. No se encontraron diferencias en la producción de estructuras reproductivas (inflorescencias, infrutescencias) entre el inicio del experimento y al cabo de un año, ni en la producción de frutos al cabo de un año entre tratamientos y el testigo. Se encontró una respuesta significativa de la producción de hojas al tamaño de la planta y a la intensidad de defoliación, pero esta respuesta dependió de la combinación de niveles de estas variables. La producción foliar aumentó conforme al incremento en la intensidad de cosecha (defoliación) y al incremento en las categorías de tamaños. Sólo se encontraron diferencias entre los tratamientos de defoliación dentro de la clase de tamaño 3. Sin embargo, debido a posibles efectos a largo plazo, será necesario incrementar los tiempos de observación para identificar los tratamientos que, después de un primer evento de crecimiento compensatorio, muestren efectos negativos que permitan sugerir intensidades de aprovechamiento sustentable a mediano y largo plazo.


4.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Sapling survival and growth of coniferous and broad-leaved trees in successional highland habitats in Mexico
Quintana Ascencio, Pedro F. (1959-) ; Ramírez Marcial, Neptalí (coaut.) (1963-) ; González Espinosa, Mario (coaut.) (1950-) ; Martínez Icó, Miguel (coaut.) ;
Clasificación: AR/634.956097275 / S2
Contenido en: Applied Vegetation Science Vol. 7, no. 1 (2004), p. 81-88 ISSN: 1402-2001
Cerrar
SIBE Campeche
ECO040003800 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010018911 (Disponible) , B5619 (Disponible)
Disponibles para prestamo: 2
Cerrar
SIBE Tapachula
ECO020004779 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Villahermosa
ECO050002336 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Inglés |
Resumen en inglés

We assessed survival and growth of transplanted saplings of understory broad-leaved trees (Oreopanax xalapensis, Rapanea juergensenii, Rhamnus sharpii and Ternstroemia lineata) and canopy conifers (Abies guatemalensis, Pinus ayacahuite and P. pseudostrobus) into Grassland (GR), Mid-Successional Oak Forest( MS), and Old-Growth Oak Forest( OF) stands in the central highlands of Chiapas, Mexico. A total of 727 plants were monitored over eight years.The results suggest habitat preferences of the studied species that should be considered for their conservation oriented management. Conifers had highest survival and growth in GR,while broad-leavet drees survived better under sparse canopy in MS, but grew tallest in full light.Saplings of all species in dense canopy sites in OF wer smaller, and the survival of conifers was lower.An integrated response in dex( IRI) calculated for each species with survival and relative growth rates showed similar trends. Re-introduction of the endangered A. guatemalensis is possible in open habitats if fire, trampling and grazing are suppressed. Open habitats in current manmade landscapes in the highlands of Chiapas may limit the establishment of understory trees requiring partial shade. Inclusion of such species in restoration programs has not been usual so far;yet, local and global interest in native species for such programs is increasing. In formation on the response of these kind of species in contrasting habitats may help to incorporate them in the management of high-diversity forests that may follow pine plantations


5.
Artículo
*En hemeroteca, SIBE-San Cristóbal
A fire-explicit population viability analysis of hypericum cumulicola in Florida Rosemary Scrub
Quintana Ascencio, Pedro F. (1959-) ; Menges, Eric S. (coaut.) ; Weekley, Carl W. (coaut.) ;
Clasificación: AR/582.12 / QU57
Contenido en: Conservation Biology Vol. 17, no. 2 (April 2003), p. 433-449 ISSN: 0888-8892
Cerrar
SIBE Campeche
ECO040001559 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
ECO030000182 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
B1972 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Tapachula
ECO020006073 (Disponible) , ECO020002604 (Disponible)
Disponibles para prestamo: 2
Cerrar
SIBE Villahermosa
ECO050000212 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en español

Los administradores de tierras que buscan restablecer regímenes históricos de incendios necesitan dirección sobre la manera de aplicar los incendios prescritos para promover la persistencia poblacional de especies amenazadas. Exploramos los riesgos de extinción de Hypericum cumulicola, una planta dependiente de incendios endémica de la cordillera del Lake Wales, Florida ( E.U.A. ). Usamos modelos de matrices poblacionales estocásticos y determinísticos basados en seis censos ( 1994–1999 ) y datos de varios experimentos de germinación y supervivencia de plántulas para comparar la demografía y las probabilidades de extinción de H. cumulicola bajo diferentes regímenes de incendios. La variación ambiental asociada con el sitio, el año y la precipitación de invierno se incluyó en estos modelos. Estimamos el tiempo de extinción de poblaciones de diferentes tamaños sin quemas y las probabilidades de extinción bajo regímenes sin incendios, con incendios a intervales regulares diferentes y a intervalos que alternan entre periodos cortos y largos. Aún las poblaciones relativamente grandes de miles de individuos subsiguientes a un incendio inicial pueden volverse localmente extintas en 300–400 años sin incendios adicionales.

La probabilidad de extinción disminuyó cuando los intervalos entre incendios disminuyeron. Los intervalos entre incendios> 50 años resultaron en una extinción considerable después de 200 años. Los ciclos con intervalos altamente escalonados de intervalos cortos y largos de retorno de incendios causaron probabilidades de extinción ligeramente más altas cuando se compararon con intervalos regulares de retorno de incendios. Las simulaciones fueron sensibles a estimaciones de sobrevivencia en los bancos de semilla. Se requerirá una administración activa para restablecer regímenes favorables de incendios en áreas donde los incendios han sido eliminados. Sin embargo, para mantener la biodiversidad, los administradores deben considerar regímenes de incendios variables para satisfacer los requerimientos de una variedad de especies con diferentes historias de vida.

Resumen en inglés

Land managers seeking to reestablish historical fire regimes need guidance on how to apply prescribed fire to promote the population persistence of endangered species. We explored extinction risks of Hypericum cumulicola, a fire-dependent plant endemic to the Lake Wales Ridge, Florida ( U.S.A ). Stochastic and deterministic matrix population models based on six censuses ( 1994–1999 ) and data from several germination and seedling survival experiments were used to compare H. cumulicola demography and extinction probabilities under different fire regimes. Environmental variation associated with site, year, and winter precipitation was included in these models. We estimated time to extinction of unburned populations of different sizes and the probabilities of extinction under no fire, different regular fire-return intervals, and alternating short and long fire-return intervals. Following an initial fire, even relatively large populations of thousands of individuals may become locally extinct within 300–400 years without additional fires. Extinction probability declined as intervals between fires decreased. Fire intervals openface>50 years resulted in an appreciable extinction probability after 200 years. Cycles of highly staggered short and long fire-return intervals caused slightly higher chances of extinction than regular fire-return intervals. The simulations were sensitive to estimates of survival in the seed bank. Active management will be required to restore favorable fire regimes in areas where fire has been suppressed. To maintain biodiversity, managers should consider variable fire regimes to match the requirements of a variety of species with different life histories.


6.
Capítulo de libro
Modeling the effects of disturbance, spatial variation, and environmental heterogeneity on population viability of plants: E. S. Menges and Pedro Francisco Quintana-Ascencio
Menges, Erick S. ; Quintana Ascencio, Pedro F. (coaut.) (1959-) ;
Clasificación: AR/577.2 / M4
Contenido en: Population viability in plants: conservation, management, and modeling of rare plants / C. A. Brigham, M. W. Schwartz, (eds.) Berlin: Spring-Verlag, 2003 p. 289-311 ISBN:3540439099
Bibliotecas: Campeche , Chetumal , San Cristóbal
Cerrar
SIBE Campeche
ECO040001285 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
ECO030000200 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010012518 (Disponible)
Disponibles para prestamo: 1

7.
- Artículo con arbitraje
*En hemeroteca, SIBE-Tapachula
Recruitment rates exhibit high elasticity and high temporal variation in populations of a short-lived perennial herb
Picó, F. Xavier ; Quintana Ascencio, Pedro F. (coaut.) (1959-) ; Menges, Erick S. (coaut.) ; López Barrera, Fabiola (coaut.) ;
Contenido en: Oikos Vol. 103, no. 1 (October 2003), p. 69-74 ISSN: 0030-1299
Bibliotecas: Tapachula
Cerrar
SIBE Tapachula
B3101 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-Tapachula
PDF
Resumen en: Inglés |
Resumen en inglés

Empirical studies for different life histories have shown an inverse relationship between elasticity (i.e. the proportional contribution to population growth rate) and temporal variation in vital rates. It is accepted that this relationship indicates the effect of selective pressures in reducing variation in those life-history traits with a major impact on fitness. In this paper, we sought to determine whether changes in environmental conditions affect the relationship between elasticity of vital rates and their temporal variation, and whether vital rates with simultaneously large elasticity and temporal variation might represent a characteristic life-history strategy. We used demographic data on 13 populations of the short-lived Hypericum cumulicola over 5–6 years, in three time-since-fire classes. For each population of each time-since-fire, we computed the mean matrix over years and its respective elasticity matrix, and the coefficients of variation in matrix entries over study years as an estimate of temporal variability. We found that mean elasticity negatively significantly correlated with temporal variation in vital rates in populations (overall eight out of 13) included in each time-since-fire. However, seedling recruitment exhibited both high elasticity and high temporal variation in almost all study populations.

These results indicated that (1) the general relationship between elasticity and temporal variation in vital rates was not modified by environmental changes due to time-since-fire, and (2) high elasticity and high temporal variation in seedling recruitment in H. cumulicola is a particular trait of the species' life history. After seed survival in the soil seed bank, seedling recruitment represents the most important life-history trait influencing H. cumulicola population growth rate (and fitness). The high temporal variability in seedling recruitment suggests that this trait is determined by environmental cues, leading to an increase in population size and subsequent replenishment of the seed bank in favorable years.


8.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Assessing scrub buckwheat population viability in relation to fire using multiple modeling techniques
Satterthwaite, William H. ; Menges, Erick S. (coaut.) ; Quintana Ascencio, Pedro F. (coaut.) (1959-) ;
Clasificación: AR/583.917 / S2
Contenido en: Ecological Applications Vol. 12, no. 6 (December 2002), p. 1672-1687 ISSN: 1051-0761
Bibliotecas: Campeche , Chetumal , San Cristóbal
Cerrar
SIBE Campeche
ECO040001286 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
ECO030000201 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
B8594 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
PDF PDF
Resumen en: Inglés |
Resumen en inglés

We used a variety of modeling approaches to assess the effects of fire on the demography and population viability of scrub buckwheat (Eriogonum longifolium var. gnaphalifolium), a threatened herb endemic to periodically burned xeric uplands in central Florida, USA. We compared the management implications of different approaches. Using demographic data from ten years including five fires, we constructed Lefkovitch matrix models of scrub buckwheat populations in unburned habitats for populations experiencing a burn and for populations one year after burning. Deterministic analysis of the unburned matrices predicted relatively stable populations in unburned habitats using optimistic fertility estimates (λ = 1.002, 95% CI 0.975-1.033). but almost certain decline given pessimistic fertility estimates (λ = 0.981, 0.962-1.003). Burned populations are always predicted to increase (CI on λ > 1.08). Numerical calculations of single-year growth rates based on the expected stable stage distribution of an unburned population yielded positive, but lower, growth rates.

The λ's calculated for periodically burned populations had confidence intervals entirely above 1 for fire return intervals shorter than 20 yr (optimistic) or 5 yr (pessimistic). Stochastic simulations yielded highly uncertain estimates of the probability of quasi-extinction over 250 yr, with only fire return intervals shorter than 20 yr (optimistic) or 5 yr (pessimistic) yielding quasi-extinction confidence intervals entirely below 1. Population growth rates in partially burned areas increased linearly with the proportion burned. The results of these density-independent simulations remained virtually unchanged (maximum difference of 5.2%) by introducing plausible population ceilings.. Regression and stasis transitions had the highest elasticities for unburned populations, while fecundity elasticities were relatively greater for burn years. Transient elasticity analysis on total population size of simulated single-year post-fire growth and on the population vector five years in the future showed broadly similar patterns to standard elasticities, although the standard analysis assigned higher elasticity values to transitions contributing to future reproductive potential. Fire management is important to encouraging viable populations. Our analysis suggests minimum fire return intervals of 20 yr (optimistic) or 5 yr (pessimistic). These fire return intervals are consistent with those often used in the sandhill and oak-hickory scrub habitats of scrub buckwheat.


9.
Libro

10.
Capítulo de libro
*Solicítelo con su bibliotecario/a
Transformación de los bosques en dos municipios mayas de la zona norte de Chiapas, México
Ochoa Gaona, Susana ; Morales Hernández, María Cristina (coaut.) ; Quintana Ascencio, Pedro F. (coaut.) (1959-) ; Cigarroa López, Miguel Ángel (coaut.) ; Montoya Gómez, Guillermo (coaut.) ;
Contenido en: I congreso internacional de investigación y transferencia de tecnología agropecuaria, Chiapas 2002 / edición: Néstor Espinosa Paz, Ma. Magdalena Pérez Salgado, Eduardo R. Garrido Ramírez, Ramón Mariaca Méndez, Orlando López Báez, María Guadalupe Gómez Jiménez Tuxtla Gutiérrez, Chiapas, México : Fundación Produce Chiapas, 2002 página 104-104
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
35661-20 (Disponible)
Disponibles para prestamo: 1
Nota: Solicítelo con su bibliotecario/a