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28 resultados encontrados para: AUTOR: Philpott, Stacy M.
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1.
- Artículo con arbitraje
Agroecological pest management in the city: experiences from California and Chiapas
Morales, H. ; Ferguson, Bruce G. (coaut.) (1967-) ; Marín, Linda E. (coaut.) ; Gutiérrez Navarrete, Dario (coaut.) ; Bichier, Peter (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Sustainability Vol. 10, no. 6, 2068 (June 2018) ISSN: 2071-1050
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Resumen en: Inglés |
Resumen en inglés

Urban gardens are a prominent part of agricultural systems, providing food security and access within cities; however, we still lack sufficient knowledge and general principles about how to manage pests in urban agroecosystems in distinct regions. We surveyed natural enemies (ladybeetles and parasitoids) and conducted sentinel pest removal experiments to explore local management factors and landscape characteristics that influence the provisioning of pest control services in California, USA, and Chiapas, Mexico. We worked in 29 gardens across the two locations. In each location, we collected data on garden vegetation, floral availability, ground cover management, and the percentage of natural, urban, and agricultural land cover in the surrounding landscape. We sampled ladybeetles, Chalcidoidea, and Ichneumonoidea parasitoids with sticky traps, and monitored the removal of three different pest species. Ladybeetle abundance did not differ between locations; abundance decreased with garden size and with tree cover and increased with herbaceous richness, floral abundance, and barren land cover. Chalcicoidea and Ichneumonoidea parasitoids were more abundant in Chiapas.

Chalcicoidea abundance decreased with herbaceous richness and with urban cover. Ichneumonoidea abundance increased with mulch and bare ground cover, garden size, garden age, and with agriculture land cover but decreased with tree richness and urban cover. Predators removed between 15–100% of sentinel prey within 24 h but prey removal was greater in California. Generally, prey removal increased with vegetation diversity, floral abundance, mulch cover, and urban land cover, but declined with vegetation cover and bare ground. Although some factors had consistent effects on natural enemies and pest control in the two locations, many did not; thus, we still need more comparative work to further develop our understanding of general principles governing conservation biological control in urban settings.


2.
- Artículo con arbitraje
Influences of species interactions with aggressive ants and habitat filtering on nest colonization and community composition of arboreal twig-nesting ants
Philpott, Stacy M. (autora) ; Serber, Zachary (autor) ; De la Mora, Aldo (autor) ;
Disponible en línea
Contenido en: Environmental Entomology Vol. 47, no. 2 (April 2018), p. 309–317 ISSN: 1938-2936
Resumen en: Inglés |
Resumen en inglés

Ant community assembly is driven by many factors including species interactions (e.g., competition, predation, parasitism), habitat filtering (e.g., vegetation differences, microclimate, food and nesting resources), and dispersal. Canopy ant communities, including dominant and twig-nesting ants, are structured by all these different factors, but we know less about the impacts of species interactions and habitat filters acting at the colonization or recruitment stage. We examined occupation of artificial twig nests placed in shade trees in coffee agroecosystems. We asked whether species interactions—aggression from the dominant canopy ant, Azteca sericeasur Longino (Hymenoptera: Formicidae)—or habitat filtering—species of tree where nests were placed or surrounding vegetation—influence colonization, species richness, and community composition of twig-nesting ants. We found 20 species of ants occupying artificial nests. Nest occupation was lower on trees with A. sericeasur , but did not differ depending on tree species or surrounding vegetation. Yet, there were species-specific differences in occupation depending on A. sericeasur presence and tree species. Ant species richness did not vary with A. sericeasur presence or tree species. Community composition varied with A. sericeasur presence and surrounding vegetation. Our results suggest that species interactions with dominant ants are important determinants of colonization and community composition of twig-nesting ants. Habitat filtering at the level of tree species did not have strong effects on twig-nesting ants, but changes in coffee management may contribute to differences in community composition with important implications for ant conservation in agricultural landscapes, as well as biological control of coffee pests.


3.
- Artículo con arbitraje
*Solicítelo con su bibliotecario/a
Response of ground spiders to local and landscape factors in a Mexican coffee landscape
Marín, Linda (coaut.) ; Philpott, Stacy M. (coaut.) ; De la Mora, Aldo (coaut.) ; Ibarra Núñez, Guillermo (coaut.) ; Tryban, Stephen (coaut.) ; Perfecto, Ivette (coaut.) ;
Contenido en: Agriculture, Ecosystems and Environment Vol. 222, (April 2016), p. 80–92 ISSN: 0167-8809
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

In order to secure the provisioning of ecosystem services, detailed analyses of the relationship between biodiversity and agriculture are required. We studied ground spider diversity in a 52 km² coffee landscape in Southern Mexico, and asked the following questions. (1) How do coffee management variables and local microhabitat variables change among coffee agroecosystems and forest sites and across seasons? (2) How does coffee management affect ground spider richness, abundance, and composition? (3) How do local and landscape factors in fl uence ground spider richness and abundance? and (4) What role does seasonality play in shaping ground spider communities? During the dry season and rainy season of 2011 we sampled ground active spiders using pitfall traps from high and low shade coffee agroecosystems (27 sites) and from forest (10 sites). On local scale, for each 20 m × 20 m site we measured leaf litter variables, invertebrate dry biomass, slope of the terrain and elevation, and management variables such as canopy cover, shade tree richness, shade tree density and proportion of Inga trees. At the landscape scale, we measured distance to the nearest forest and percent of forest in buffers of 500 m. Results show that agricultural management had a strong influence on spider richness and abundance. Across seasons, local spider richness and abundance had or tended to have higher values in the low-shade coffee. Spider richness and abundance were strongly in fl uenced by physiographic and local predictors and weakly by landscape predictors. Furthermore, predictors varied with seasonality, with slope of the terrain being the strongest predictor in the dry season and canopy cover being the strongest predictor in the rainy season. We conclude that ground active spiders in this coffee landscape are greatly in fl uenced by coffee management and local characteristics.


4.
- Artículo con arbitraje
Local and Landscape Drivers of Ant Parasitism in a Coffee Landscape
De la Mora, Aldo ; Pérez Lachaud, Gabriela (coaut.) ; Lachaud, Jean Paul (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Environmental Entomology Vol. 44, no. 4 (Aug. 2015), p. 939-950 ISSN: 0046-225X
Resumen en: Inglés |
Resumen en inglés

Parasitism of ants that nest in rotting wood by eucharitid wasps was studied in order to examine whether habitat and season influence ant parasitism, vegetation complexity and agrochemical use correlate with ant parasitism, and whether specific local and landscape features of agricultural landscapes correlate with changes in ant parasitism. In a coffee landscape, 30 coffee and 10 forest sites were selected in which local management (e.g., vegetation, agrochemical use) and landscape features (e.g., distance to forest, percent of rustic coffee nearby) were characterized. Rotten logs were sampled and ant cocoons were collected from logs and cocoons were monitored for parasitoid emergence. Sixteen ant morphospecies in three ant subfamilies (Ectatomminae, Ponerinae, and Formicinae) were found. Seven ant species parasitized by two genera of Eucharitidae parasitoids (Kapala and Obeza) were reported and some ant–eucharitid associations were new. According to evaluated metrics, parasitism did not differ with habitat (forest, high-shade coffee, low-shade coffee), but did increase in the dry season for Gnamptogenys ants. Parasitism increased with vegetation complexity for Gnamptogenys and Pachycondyla and was high in sites with both high and low agrochemical use. Two landscape variables and two local factors positively correlated with parasitism for some ant genera and species. Thus, differences in vegetation complexity at the local and landscape scale and agrochemical use in coffee landscapes alter ecological interactions between parasitoids and their ant hosts.


5.
- Artículo con arbitraje
Local, landscape, and diversity drivers of predation services provided by ants in a coffee landscape in Chiapas, Mexico
De la Mora Rodríguez, Aldo Alejandro ; García Ballinas, José Álvaro (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Agriculture, Ecosystems and Environment Vol. 201, (March 2015), p. 83–91 ISSN: 0167-8809
PDF
Resumen en: Inglés |
Resumen en inglés

Agricultural management and the landscape surrounding farms impact biological diversity and ecosystem services, such as predation, in agroecosystems. Diversified coffee agroecosystems harbor biodiversity, and maintain ecosystem services, especially when in complex landscapes, and when diversity of organisms providing services is maintained. But few have examined whether biological diversity, per se, or the local and landscape habitat features are stronger drivers of the services provided. We studied the relationships between local characteristics associated with agricultural management (vegetation complexity and agrochemical use), landscape surroundings of farms, abundance and richness of ants, and predation services provided by ants in a tropical coffee landscape. Specifically, we tested whether: (1) ants remove prey items and prey removal differs in the wet and dry season, (2) ant prey removal differs in farms that vary in vegetation complexity and agrochemical use, (3) ant prey removal differs with changes in ant abundance and species richness, and (4) ant prey removal differs with changes in local and landscape characteristics. We established sites across a range of coffee management systems, at varying distances to forest fragments, and in forest fragments and examined prey removal by ants on the ground, coffee branches, and shade tree trunks in the wet and dry season. Prey removal did not differ with season. Prey removal on the ground increased within increases in ant abundance and richness, and number of hollow coffee twigs.

Prey removal on coffee plants decreased with vegetation complexity, but increased with ant abundance and richness, coffee density (a local factor), and rustic coffee within 200 m (a landscape factor). Prey removal on trees declined with vegetation complexity, but increased with abundance and richness of ants. Characteristics of the ant community were consistent predictors of prey removal, whereas local and landscape habitat features were less important, and only three habitat features correlated with prey removal. Our results demonstrate the positive effects of ant diversity for predatory function, and that promoting pest control services within coffee agroecosystems may be best accomplished by manipulating ant abundance and richness, or vegetation factors that correlate with ants.


6.
Tesis - Doctorado
Hormigas en cafetales: estudio sobre la calidad de la matriz en fincas cafetaleras en el Soconusco, Chiapas / Aldo Alejandro de la Mora Rodríguez
De la Mora Rodríguez, Aldo Alejandro ; Ibarra Núñez, Guillermo (director) ; Philpott, Stacy M. (codirectora) ; Lachaud, Jean Paul (asesor) ; Pérez Lachaud, Gabriela (asesora) ; Soto Pinto, Lorena (asesora) (1958-) ;
Tapachula, Chiapas, México : El Colegio de la Frontera Sur , 2014
Clasificación: TE/595.796097275 / M67
Cerrar
SIBE Campeche
ECO040005482 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Chetumal
ECO030008232 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE San Cristóbal
ECO010017601 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Tapachula
ECO020013100 (Disponible)
Disponibles para prestamo: 1
Cerrar
SIBE Villahermosa
ECO050005678 (Disponible)
Disponibles para prestamo: 1
Resumen en español

La intensificación de agroecosistemas afecta la diversidad de la flora y fauna. Los objetivos fueron: conocer los efectos de la intensificación agronómica de cafetales y de los remanentes de bosque sobre la diversidad de hormigas, la relación entre la diversidad de hormigas y la remoción de insectos presa por parte de éstas y finalmente, analizar cómo afectan las variables locales y de paisaje a la tasa de parasitismo en las diferentes especies de hormigas en un agroecosistema de café. Se establecieron 40 sitios experimentales (400 m² cada uno) en siete fincas de café y en fragmentos de bosque en el Soconusco, Chiapas. Se calculó un índice de complejidad de vegetación (IVC), y mediante encuestas al personal de las fincas sobre el uso y frecuencia de aplicación de agroquímicos se elaboró un índice de agroquímicos (IA). Con los datos de la vegetación se clasificaron los 40 sitios experimentales en diferentes manejos del área de estudio en: monocultivos (17 sitios), policultivos (13 sitios) y bosques (10 sitios). Con los programas ArcView, y ArcMap se calcularon las siguientes variables de paisaje: distancia de cada sitio al borde del bosque, áreas con radios de 50, 200 y 500 m para sitios de bosques y de café de tipo rústico. En cada sitio, en las temporadas de secas y lluvias, se colectaron las hormigas del suelo, cafetos y arboles con diversos métodos de muestreo.

Los resultados de esta investigación sugieren que los factores de manejo agronómico y la influencia de fragmentos de bosque afectan la diversidad y abundancia de hormigas e indirectamente influyen positivamente en los servicios ecosistémicos que las hormigas ofrecen. Sin embargo, la intensidad de parasitismo sufrido por las hormigas es afectada principalmente por factores del paisaje, la cantidad de humus y numero de pupas para ciertos grupos de hormigas. Se propone realizar acciones de diversificación de las zonas de café empleando diferentes especies de árboles para sombra (preferentemente nativos) o plantar diversas especies de Inga, con el fin de proveer refugio y alimentación para los diferentes organismos que existen y así favorecer las interacciones ecológicas entre ellos, favoreciendo una mejor calidad de la matriz agrícola que promovería sustentabilidad, economía y salud de los productores en la región.

Índice

Resumen
Capítulo I
1.1. Introducción General
1.1.1. Contexto global de la biodiversidad
1.1.2. Agroecosistemas de café: Factores de intensificación y de paisaje que inciden en la funcionalidad del agroecosistema
1.1.3. Hormigas como indicadoras de diversidad y su importancia ecológica
1.2 Hipótesis y Objetivos
1.2.1. Hipótesis general e hipótesis particulares
1.2.2 Objetivo general y objetivos particulares
1.3. Metodología General
1.3.1. Caracterización del área de estudio y técnicas de muestreo utilizadas
1.3.2. Análisis estadísticos
Capítulo II. Factores locales y de paisaje promueven la biodiversidad de cuatro grupos de hormigas en paisajes cafetaleros (Local and landscape drivers of biodiversity of four guilds of ants in coffee landscapes. Biodiversity Conservation, 22:871-888)
Capítulo III. Factores locales, del paisaje y de diversidad promueven los servicios ecosistemicos de depredación por hormigas en cafetales (Local, landscape, and diversity drivers of predation services provided by ants in coffee landscapes. Agriculture, Ecosystems and Environment, Manuscript re-submitted
Number : AGEE10440)
Capítulo IV. Factores locales y de paisaje promueven el parasitismo en un paisaje de café (Local and landscape drivers of ant parasitism in a coffee landscape. Environmental Entomology, Manuscrito sometido)
Capítulo V. Conclusiones y Recomendaciones
Capítulo VI.- Literatura Citada
Anexo 1
Acuse de artículo aceptado: Local and landscape drivers of biodiversity of four guilds of ants in coffee landscapes. Biodiversity Conservation, 22:871-888
Anexo 2
Normas editoriales de Agriculture, Ecosystems, and Environment


7.
- Artículo con arbitraje
Local and landscape drivers of biodiversity of four groups of ants in coffee landscapes
De la Mora, Aldo ; Murnen, C. J. (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Biodiversity and Conservation Vol. 22, no. 4 (2013), p. 871–888 ISSN: 0960-3115
PDF
Resumen en: Inglés |
Resumen en inglés

Agriculture of varying management intensity dominates fragmented tropical areas and differentially impacts organisms across and within taxa. We examined impacts of local and landscape characteristics on four groups of ants in an agricultural landscape in Chiapas, Mexico comprised of forest fragments and coffee agroecosystems varying in habitat quality. We sampled ground ants found in leaf litter and rotten logs and arboreal ants found in hollow coffee twigs and on tree trunks. Then using vegetation and agro- chemical indices and conditional inference trees, we examined the relative importance of local (e.g. vegetation, elevation, agrochemical) and landscape variables (e.g. distance to and amount of nearby forest and rustic coffee) for predicting richness and abundance of ants. Leaf litter ant abundance increased with vegetation complexity; richness and abun- dance of ants from rotten logs, twig-nests, and tree trunks were not affected by vegetation complexity. Agrochemical use did not affect species richness or abundance of any ant group. Several local factors (including humus mass, degree of decay of logs, number of hollow twigs, tree circumference, and absence of fertilizers) were significant positive predictors of abundance and richness of some ant groups. Two landscape factors (forest within 200 m, and distance from forest) predicted richness and abundance of twig-nesting and leaf litter ants. Thus, different ant groups were influenced by different characteristics of agricultural landscapes, but all responded primarily to local characteristics. Given that ants provide ecosystem services (e.g. pest control) in coffee farms, understanding ant responses to local and landscape characteristics will likely inform farm management decisions.


8.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Do species sorting and mass effects drive assembly in tropical agroecological landscape mosaics
Livingston, George A. ; Philpott, Stacy M. (coaut.) ; De la Mora Rodríguez, Aldo Alejandro (coaut.) ;
Contenido en: Biotropica Vol. 45. no. 1 (January 2012), p. 10-17 ISSN: 0006-3606
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
51646-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en español

Evaluaciones recientes sobre la diversidad en agroecosistemas tropicales han mostrado una alta diversidad taxonómica y funcional en sistemas con un bajo manejo agronómico de intensificación. Esta diversidad es el producto del ensamblaje en la comunidad. Sin embargo, debido a que los agroecosistemas son ambientes nuevos comparados con sistemas naturales, y ocurren en paisajes fragmentados, el proceso de ensamblaje que se forman en las comunidades de agroecosistemas es pobremente entendible. Dos modelos han sido propuestos para explicar el ensamblaje a nivel de paisaje: (1) Compromiso en realización de las especies a través de los hábitats (ordenamiento de especies) y (2) El dinamismo de fuente sumidero entre hábitats con calidades diferentes (efecto de masa). Estos modelos no han sido evaluados en agroecosistemas tropicales ampliamente. Utilizamos una extensa base de datos en una comunidad de hormigas tropicales que anidan en ramas de cinco microhabitats en cafetales de sombra, con el fin de evaluar ambos modelos (ordenamiento de especies y efecto de masa) o un modelo mixto. Para estudiar las diferencias entre estos modelos realizamos: análisis de similitud-comunidad y una prueba de varianza de descomposición sobre un microhábitat focal (finca de café con sombra moderada) para particionar la varianza de la comunidad en un componente espacial y ambiental. Para identificar la fuente de hábitat por efecto de masa y evaluar su solidez, medimos la dispersión de alados (reinas aladas), nidos artificiales, tamaño de nidos y colonias en árboles y plantas de café.

Encontramos un significancia ambiental y espacial, así como evidencia para ambos modelos:ordenamiento de especies y efecto de masa. Así también, que el efecto de modelo de ordenamiento de especies ocurre entre las especies más comunes, mientras el efecto de masa puede ser mas entre especies raras que provienen del dosel. Nuestros resultados indican que ambos modelos de metacomunidad (ordenamiento de especies y efecto de masa) ocurren en fragmentos de paisajes tropicales, pero estos pueden no ser evaluados igualmente en todas las especies en comunidades, gradientes de hábitats o en tiempo.

Resumen en inglés

Recent assessments of biodiversity in tropical agroecosystems have revealed surprisingly high functional and taxonomic diversity in systems with low management intensity. This biodiversity is the product of community assembly. Because agroecosystems are novel ecosystems and occur in landscape mosaics, the assembly processes generating communities in agroecosystems are poorly resolved. Broadly, two models have been proposed to explain landscape assembly: trade-offs in species performance across habitats (species sorting) and source-sink dynamics between habitats of differential quality (mass effects). These models are largely untested in tropical agroecosystems. We utilize an extensive data set on a tropical twig-nesting ant community from five microhabitat types in a shaded coffee agroecosystem to test for species sorting, mass effects, or a mixed model. To test among these models, we used community similarity and a variance decomposition on a focal microhabitat (a moderate-shade coffee farm) to partition community variance into spatial and environmental components. To identify the source habitat for mass effects and assess their strength, we measured dispersing alates (winged reproductives), artificial nests, and colony and nest size in shade trees and coffee. We found significant environmental and spatial signal and evidence for both species sorting and mass effects. We find sorting occurs among common species, but that mass effects are prevalent among rare species and likely originate in the shade trees. Our results indicate that both metacommunity models occur in tropical landscape mosaics, but they may not apply equally to all species in communities, habitat gradients, or timescales.


9.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Azteca instabilis ants and the defence of a coffee shade tree: an ant-plant association without mutual rewards in Chiapas, México
Gonthier, David J. ; Pardee, Gabriella L. (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Journal of Tropical Ecology Vol. 26, part 3 (January 2010), p. 343-346 ISSN: 0266-4674
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
49288-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Inglés |
Resumen en inglés

Ants (Hymenoptera: Formicidae) are important predators of herbivorous insects on plants (Rosumek et al. 2009). Ant removal or absence may result in negative indirect effects on plants, as herbivore abundance and herbivory increase and plant growth and reproduction decline (Rosumek et al. 2009, Schmitz et al. 2000). Ant presence on plants often results from a mutualistic interaction. For example, strong highly coevolved ant–plant mutualisms are found on myrmecophytic plants that house ants in domatia (specialized nesting sites). Weaker mutualistic associations are found with myrmecophilic plants that only offer extra-floral nectaries (EFNs) or food bodies to attract ants, or on other plants hosting honeydew-producing hemipterans (indirect ant–plant interactions) that mediate ant abundance (Hölldobler & Wilson 1990). However, in most cases, plants and arboreal ants form more passive associations, where ants nest in the natural cavities of branches or bark, or construct carton nests on plant substrates (Hölldobler & Wilson 1990) and the only reward plants offer these ants is the use of their substrates. In these situations the indirect effect of ants on plants is merely by chance, a byproduct of ant presence (byproduct association).


10.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Epiphyte biodiversity in the coffee agricultural matrix: canopy stratification and distance from forest fragments
Moorhead, Leigh C. (autor) ; Philpott, Stacy M. (autora) ; Bichier, Peter (autor) ;
Contenido en: Conservation Biology Vol. 24, no. 3 (June 2010), p. 737-746 ISSN: 0888-8892
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
49277-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Español | Inglés |
Resumen en español

La calidad de la matriz agrícola afecta profundamente a la biodiversidad y la dispersión en áreas agrícolas. Los agroecosistemas cafetaleros con una vegetación compleja mantienen riqueza de especies a mayores distancias del bosque. Las epífitas colonizan el dosel de árboles y proporcionan recursos para aves e insectos y, por lo tanto, los efectos de la producción agrícola sobre las epífitas pueden afectar a otras especies. Comparamos la diversidad, composición, diversidad y estratificación vertical de epífitas en un fragmento de bosque y en dos fincas cafetaleras con diferente intensidad de manejo en el sur de México. También examinamos la distribución espacial de epífitas respecto al fragmento de bosque para evaluar la calidad de los dos tipos de matriz para la conservación de epífitas. Muestreamos las epífitas vasculares en un fragmento de bosque, una finca con sombra policultivo y una con sombra monocultivo a 100 m, 200 m y 400 m del bosque. La riqueza de epífitas y orquídeas fue mayor en el bosque que en el bosque que el monocultivo pero la riqueza fue similar en el bosque y el policultivo. La composición de especies de epífitas difirió con el tipo de hábitat, pero no con la distancia al bosque.

En el bosque, las epífitas se distribuyeron en el dosel de los árboles, pero en las fincas se distribuyeron principalmente sobre los troncos y ramas mayores. La riqueza y similitud de especies de epífitas disminuyeron con la distancia al fragmento de bosque en elmonocultivo, pero la riqueza y la similitud con las especies de bosque no declinaron con la distancia al bosque en el policultivo. Esto sugiere que el café policultivo tiene un mayor valor de conservación. En contraste, el café monocultivo probablemente es un hábitat vertedero para epífitas en dispersión desde los bosques. Las fincas cafetaleras difieren de los bosques en términos del hábitat que proporcionan y la composición de especies, por lo tanto la protección de fragmentos de bosque es esencial para la conservación de epífitas. Sin embargo, las fincas cafetaleras con vegetación compleja pueden contribuir a la conservación de epífitas mejor que otros usos de suelo en los paisajes agrícolas.

Resumen en inglés

Quality of the agricultural matrix profoundly affects biodiversity and dispersal in agricultural areas. Vegetatively complex coffee agroecosystemsmaintain species richness at larger distances from the forest. Epiphytes colonize canopy trees and provide resources for birds and insects and thus effects of agricultural production on epiphytes may affect other species. We compared diversity, composition, and vertical stratification of epiphytes in a forest fragment and in two coffee farms differing in management intensity in southern Mexico. We also examined spatial distribution of epiphytes with respect to the forest fragment to examine quality of the two agricultural matrix types for epiphyte conservation. We sampled vascular epiphytes in a forest fragment, a shade polyculture farm, and a shade monoculture farm at 100 m, 200 m, and 400 m from the forest. Epiphyte and orchid richness was greater in the forest than in the monoculture but richness was similar in the forest and polyculture farm.

Epiphyte species composition differed with habitat type, but not with distance from the forest. In the forest, epiphytes were distributed throughout tree canopies, but in the farms, epiphytes were primarily found on trunks and larger branches. Epiphyte richness and species similarity to forest species declined with distance from the forest fragment in the monoculture, but richness and similarity to forest species did not decline with distance from forest in the polyculture. This suggests polyculture coffee has greater conservation value. In contrast, monoculture coffee is likely a sink habitat for epiphytes dispersing from forests into coffee. Coffee farms differ from forests in terms of the habitat they provide and species composition, thus protecting forest fragments is essential for epiphyte conservation. Nonetheless, in agricultural landscapes, vegetatively complex coffee farms may contribute to conservation of epiphytes more than other agricultural land uses.


11.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Twig-Nesting Ants: the hidden predators of the coffee berry borer in Chiapas, México
Larsén, Asley ; M. Philpott, Stacy (coaut.) ;
Contenido en: Biotropica Vol. 42, no. 3 (May 2010), p. 342-347 ISSN: 0006-3606
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
49083-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
PDF
Resumen en: Inglés |
Resumen en inglés

Coffee is a globally important crop that is subject to numerous pest problems, many of which are partially controlled by predatory ants. Yet several studies have proposed that these ecosystem services may be reduced where agricultural systems are more intensively managed. Here we investigate the predatory ability of twig-nesting ants on the main pest of coffee, the coffee berry borer (Hypothenemus hampei) under different management systems in southwest Chiapas, Mexico. We conducted both laboratory and field experiments to examine which twig-nesting ant species, if any, can prey on free-living borers or can remove borers embedded in coffee fruits and whether the effects of the twig-nesting ant community differ with habitat type. Results indicate that several species of twig-nesting ants are effective predators of both free-living borers and those embedded in coffee fruits.

In the lab, Pseudomyrmex ejectus, Pseudomyrmex simplex, and Pseudomyrmex PSW-53 effectively removed free-living and embedded borers. In the field, abundance, but not diversity, of twig-nesting ant colonies was influenced by shade management techniques, with the highest colony abundance present in the sites where shade trees were recently pruned. However, borer removal rates in the field were significant only in the shadiest site, but not in more intensively managed sites. This study provides evidence that twig-nesting ants can act as predators of the coffee berry borer and that the presence of twig-nesting ants may not be strongly linked to shade management intensity, as has been suggested for other arthropod predators of the borer.


12.
- Artículo con arbitraje
*En hemeroteca, SIBE-Tapachula
Wood-nesting ants and their parasites in forests and coffee agroecosystems
De la Mora, Aldo ; Philpott, Stacy M. (coaut.) ;
Contenido en: Environmental Entomology Vol. 39, no. 5 (October 2010), p. 1473-1481 ISSN: 0046-225X
Bibliotecas: Tapachula
Cerrar
SIBE Tapachula
27180-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-Tapachula
Resumen en: Inglés |
Resumen en inglés

Agricultural intensification is linked to reduced species richness and may limit the effectiveness of predators in agricultural systems. We studied the abundance, diversity, and species composition of wood-nesting ants and frequency of parasitism of poneromorph ants in coffee agroecosystems and a forest fragment in Chiapas, Mexico. In three farms differing in shade management and in a nearby forest fragment, we surveyed ants nesting in rotten wood. We collected pupae of all poneromorph ants encountered, and incubated pupae for 15 d to recover emerging ant parasites. If no parasites emerged, we dissected pupae to examine for parasitism. Overall, we found 63 ant morphospecies, 29 genera, and 7 subfamilies from 520 colonies. There were no significant differences in ant richness or abundance between the different sites. However, there were significant differences in the species composition of ants sampled in the four different sites. The parasitism rates of ants differed according to site; in the forest 77.7% of species were parasitized, and this number declined with increasing intensification in traditional polyculture (40%), commercial polyculture (25%), and shade monoculture (16.6%). For three of four poneromorph species found in >1 habitat, parasitism rates were higher in the more vegetatively complex sites. The result that both ant species composition and ant parasitism differed among by site indicates that coffee management intensification affects wood-nesting ant communities. Further, coffee intensification may significantly alter interactions between ants and their parasites, with possible implications for biological control in coffee agroecosystems.


13.
- Artículo con arbitraje
*En hemeroteca, SIBE-San Cristóbal
Beyond reserves: a research agenda for conserving biodiversity in human-modified tropical landscapes
Chazdon, Robin L. ; Harvey, Celia Alice (coaut.) ; Komar, Oliver (coaut.) ; Griffith, Daniel M. (coaut.) ; Ferguson, Bruce G. (coaut.) (1967-) ; Martínez Ramos, Miguel (coaut.) ; Morales, H. (coaut.) ; Soto Pinto, Lorena (coaut.) (1958-) ; van Breugel, Michiel (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Biotropica Vol. 41, No. 2 (March 2009), p. 142-153 ISSN: 0006-3606
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
47231-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Inglés |
Resumen en inglés

To truly understand the current status of tropical diversity and to forecast future trends, we need to increase emphasis on the study of biodiversity in rural landscapes that are actively managed or modified by people. We present an integrated landscape approach to promote research in human-modified landscapes that includes the effects of landscape structure and dynamics on conservation of biodiversity, provision of ecosystem services, and sustainability of rural livelihoods. We propose research priorities encompassing three major areas: biodiversity, human-environment interactions, and restoration ecology. We highlight key areas where we lack knowledge and where additional understanding is most urgent for promoting conservation and sustaining rural livelihoods. Finally, we recommend participatory and multidisciplinary approaches in research and management. Lasting conservation efforts demand new alliances among conservation biologists, agroecologists, agronomists, farmers, indigenous peoples, rural social movements, foresters, social scientists, and land managers to collaborate in research, co-design conservation programs and policies, and manage human-modified landscapes in ways that enhance biodiversity conservation and promote sustainable livelihoods.



PDF
Resumen en: Español | Inglés |
Resumen en español

En junio de 2008 convocamos un foro-taller en Chiapas, México para potencializar alianzas entre organizaciones campesinas, conservacionistas y académicos. Los ponentes trazaron la evolución de las relaciones entre sistemas productivos, bosques y biodiversidad desde la época prehispánica hasta la actual crisis de la economía neoliberal y la agricultura industrial. También delinearon un nuevo paradigma para la conservación en donde los campesinos son protagonistas. En grupos de trabajo, elaboramos propuestas para cimentar una agenda común entre los distintos sectores representados. Las redes de cooperación emergieron como estructuras para coordinar acción y facilitar el intercambio de información y apoyo a distintas escalas geográficas. Los mercados solidarios son la confluencia de diversos intereses en dónde se pueden constituir dichas redes. También identificamos algunos temas específicos de trabajo, entre ellos: los agrocombustibles y la soberanía energética, los servicios ambientales y la educación para el campo. La biodiversidad y la soberanía alimentaria y territorial son los ejes de esta agenda de cooperación, que forma parte de una lucha internacional para reconstruir nuestros sistemas alimenticios.

Resumen en inglés

In June, 2008, we convoked a forum and workshop in Chiapas, Mexico to strengthen alliances among farmers’ organizations, conservationists and academics. Speakers outlined the evolution of the relations among production systems, forests and biodiversity from the prehispanic era through the current crisis in the neoliberal economic model and industrial agriculture. They also framed a new conservation paradigm that prioritizes the role of farmers. We formed working groups that elaborated proposals for collaboration among the participating sectors. Cooperative networks emerged as appropriate structures for coordinating action and facilitating the exchange of information and support at various geographic scales. Solidarity-based markets are a venue where diverse interests converge, favoring the formation of such networks. We also identified some specific issues for collaboration, including: agrofuels and energy sovereignty, environmental services and rural education. Biodiversity and food sovereignty are the two axes of this agenda for cooperation that forms part of an international struggle to reconstruct our food systems.


16.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Arboreal ant abundance and leaf miner damage in coffee agroecosystems in Mexico
De la Mora, Aldo ; Livingston, George A. (coaut.) ; Philpott, Stacy M. (coaut.) ;
Contenido en: Biotropica Vol. 40, no. 6 (November 2008), p. 742-746 ISSN: 0006-3606
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
46895-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
PDF
Resumen en: Español | Inglés |
Resumen en español

Agroecosistemas de café con sombra tradicionalmente tienen pocos problemas de plagas debido potencialmente a la alta abundancia y diversidad de depredadores. Sin embargo, con la intensificación de cafetales (e.g. remoción o poda de la sombra), algunos problemas de plagas aumentan. Por ejemplo, erupciones del minador de la hoja del café están vinculadas con manejo de sombra más intensivo e aumentos en el uso de agroquímicos. Evidencia demuestra que avispas parasitoides controlan al minador de la hoja del café, pero pocos estudios han examinado la función de los depredadores, como las hormigas, que son abundantes y diversas en cafetales. Acá, examinamos vinculaciones entre comunidades de hormigas arbóreas e incidencia del minador de la hoja del café en cafetales en el sur de México. Examinamos la relación entre incidencia y severidad de ataque del minador y (1) variabilidad en cobertura del dosel, densidad de árboles, diversidad de árboles, abundancia relativa de árboles de Inga spp., (2) presencia de Azteca instabilis, una hormiga arbórea y dominante, y (3) el numero de especies y de nidos de hormigas arbóreas que habitan en las ramas de café. Encontramos que diferencias en vegetación entre parcelas no correlacionaron con daño del minador. Además, presencia de A. instabilis no influyó en la presencia o severidad de daño del minador. La proporción de hojas con daño del minador bajó significativamente en áreas en donde la abundancia de hormigas que habitan en las ramas de café era mayor pero no en donde la riqueza era mayor. Estos resultados indican que la abundancia de hormigas que habitan en las ramas de café en cafetales de sombra quizás contribuye en mantener bajas las poblaciones del minador, además que hormigas proveen servicios al ecosistema importantes en agroecosistemas del café.

Resumen en inglés

Shaded coffee agroecosystems traditionally have few pest problems potentially due to higher abundance and diversity of predators of herbivores. However, with coffee intensification (e.g., shade tree removal or pruning), some pest problems increase. For example, coffee leaf miner outbreaks have been linked to more intensive management and increased use of agrochemicals. Parasitic wasps control the coffee leaf miner, but few studies have examined the role of predators, such as ants, that are abundant and diverse in coffee plantations. Here, we examine linkages between arboreal ant communities and coffee leaf miner incidence in a coffee plantation in Mexico. We examined relationships between incidence and severity of leaf miner attack and: (1) variation in canopy cover, tree density, tree diversity, and relative abundance of Inga spp. shade trees; (2) presence of Azteca instabilis, an arboreal canopy dominant ant; and (3) the number of arboreal twig-nesting ant species and nests in coffee plants. Differences in vegetation characteristics in study plots did not correlate with leaf miner damage perhaps because environmental factors act on pest populations at a larger spatial scale. Further, presence of A. instabilis did not influence presence or severity of leaf miner damage. The proportion of leaves with leaf miner damage was significantly lower where abundance of twig-nesting ants was higher but not where twig-nesting ant richness was higher. These results indicate that abundance of twig-nesting ants in shaded coffee plantations may contribute to maintenance of low leaf miner populations and that ants provide important ecosystem services in coffee agroecosystems.


17.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Biodiversity coservation, yield, and alternative products in coffee agroecosystems in Sumatra, Indonesia
Philpott, Stacy M. ; Bichier, Peter (coaut.) ; Rice, Robert A. (coaut.) ; Greenberg, Russell (coaut.) ;
Contenido en: Biodiversity and Conservation Vol. 17, no. 8 (July 2008), p. 1805-1820 ISSN: 0960-3115
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
46760-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Inglés |
Resumen en inglés

Agroecology and conservation must overlap to protect biodiversity and farmer livelihoods. Coffee agroecosystems with complex shade canopies protect biodiversity. Yet, few have examined biodiversity in coffee agroecosystems in Asia relative to the Americas and many question whether coffee agroecosystems can play a similar role for conservation. We examined vegetation, ant and bird diversity, coffee yields and revenues, and harvest of alternative products in coffee farms and forests in SW Sumatra, Indonesia near Bukit Barisan Selatan National Park (BBS). BBS is among the last habitats for large mammals in Sumatra and >15,000 families illegally cultivate coffee inside of BBS. As a basis for informing management recommendations, we compared the conservation potential and economic outputs from farms inside and outside of BBS. Forests had higher canopy cover, canopy depth, tree height, epiphyte loads, and more emergent trees than coffee farms. Coffee farms inside BBS had more epiphytes and trees and fewer coffee plants than farms outside BBS. Tree, ant, and bird richness was significantly greater in forests than in coffee farms, and richness did not differ in coffee farms inside and outside of BBS. Species similarity of forest and coffee trees, ants, and birds was generally low (<50%). Surprisingly, farms inside the park were significantly older, but farm size, coffee yields, and revenues from coffee did not depend on farm location. Farmers outside BBS received higher prices for their coffee and also more often produced other crops in their coffee fields such that incentives could be created to draw illegal farmers out of the park. We also discuss these results with reference to similar work in Chiapas, Mexico to compare the relative contribution of coffee fields to conservation in the two continents, and discuss implications for working with farmers in Sumatra towards conservation plans incorporating sustainable coffee production.


18.
- Artículo con arbitraje
*En hemeroteca, SIBE-San Cristóbal
Biodiversity loss in Latin American coffee landscapes: review of the evidence on ants, birds, and trees
Philpott, Stacy M. ; Arendt, Wayne J. (coaut.) ; Armbrecht, Inge (coaut.) ; Bichier, Peter (coaut.) ; Diestch, Thomas V. (coaut.) ; Gordon, Caleb (coaut.) ; Greenberg, Russell (coaut.) ; Perfecto, Ivette (coaut.) ; Reynoso Santos, Roberto (coaut.) ; Soto Pinto, Lorena (coaut.) (1958-) ; Tejeda Cruz, César (coaut.) ; Williams Linera, Guadalupe (coaut.) ; Valenzuela González, Jorge Ernesto (coaut.) ; Zolotoff, José Manuel (coaut.) ;
Contenido en: Conservation Biology Vol. 22, no. 5 (October 2008), p. 1093-1105 ISSN: 0888-8892
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
46889-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en español

Diversos estudios han documentado las pérdidas de biodiversidad debido a la intensificación del manejo de café (disminución de la riqueza y complejidad del dosel). Sin embargo, persisten preguntas sobre la sensibilidad relativa de diferentes taxa, especialistas de hábitat y grupos funcionales, y sí las implicaciones para la conservación de la biodiversidad varían entre regiones. Revisamos cuantitativamente los datos de estudios de biodiversidad de hormigas, aves y árboles en agroecosistemas de café para abordar las siguientes preguntas: ¿La riqueza de especies declina con la intensificación o con las características individuales de la vegetación?¿Hay pérdidas significativas de riqueza de especies en los sistemas cafetaleros en comparación con los bosques?¿Es mayor la pérdida en especies de bosque o en grupos funcionales particulares? y ¿Las aves o las hormigas son más afectadas por la intensificación? En los estudios revisados, la riqueza de hormigas y aves declinó con la intensificación del manejo y con los cambios de vegetación. La riqueza de especies de todas las hormigas y aves y la de especies de hormigas y aves de bosque fue menor en la mayoría de los agroecosistemas cafetaleros que en los bosques, pero el café rústico (cultivado bajo dosel de bosque nativo) sustentó la mayor pérdida de especies, y la pérdida de especies de hormigas, aves y árboles de bosque aumentó con la intensificación del manejo.

Las pérdidas de especies de hormigas y aves fueron similares, aunque las pérdidas de hormigas de bosque fueron más drásticas en el café rústico. La riqueza de especies de aves migratorias y de aves que forrajean en varios estratos de vegetación fueron menos afectadas por la intensificación que las especies residentes de dosel y de sotobosque. Las fincas rústicas protegieron más especies que otros sistemas cafetaleros, y la pérdida de especies dependió mayormente de la especialización de hábitat y de los atributos funcionales. Recomendamos que el bosque sea protegido, se promueva el café rústico y se restauren las fincas intensivas mediante el incremento de la densidad y riqueza de árboles nativos y permitiendo el crecimiento de epífitas. También recomendamos que las futuras investigaciones enfoquen las compensaciones potenciales entre la conservación de la biodiversidad y la forma de vida de los campesinos que producen café.

Resumen en inglés

Studies have documented biodiversity losses due to intensification of coffee management (reduction in canopy richness and complexity). Nevertheless, questions remain regarding relative sensitivity of different taxa, habitat specialists, and functional groups, and whether implications for biodiversity conservation vary across regions.We quantitatively reviewed data from ant, bird, and tree biodiversity studies in coffee agroecosystems to address the following questions: Does species richness decline with intensification or with individual vegetation characteristics? Are there significant losses of species richness in coffee-management systems compared with forests? Is species loss greater for forest species or for particular functional groups?and Are ants or birds more strongly affected by intensification? Across studies, ant and bird richness declined with management intensification and with changes in vegetation. Species richness of all ants and birds and of forest ant and bird species was lower in most coffee agroecosystems than in forests, but rustic coffee (grown under native forest canopies) had equal or greater ant and bird richness than nearby forests.

Sun coffee(grown without canopy trees) sustained the highest species losses, and species loss of forest ant, bird, and tree species increased with management intensity. Losses of ant and bird species were similar, although losses of forest ants were more drastic in rustic coffee. Richness of migratory birds and of birds that forage across vegetation strata was less affected by intensification than richness of resident, canopy, and understory bird species. Rustic farms protected more species than other coffee systems, and loss of species depended greatly on habitat specialization and functional traits. We recommend that forest be protected, rustic coffee be promoted,and intensive coffee farms be restored by augmenting native tree density and richness and allowing growth of epiphytes. We also recommend that future research focus on potential trade-offs between biodiversity conservation and farmer livelihoods stemming from coffee production.


19.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Effects of predatory ants on lower trophic levels across a gradient of coffee management complexity
Philpott, Stacy M. ; Perfecto, I. (coaut.) ; Vandermeer, John (coaut.) ;
Contenido en: Journal of Animal Ecology Vol. 77, no. 3 (May 2008) p. 505-511 ISSN: 0021-8790
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
46377-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Inglés |
Resumen en inglés

1. Ants are important predators in agricultural systems, and have complex and often strong effects on lower trophic levels. Agricultural intensification reduces habitat complexity, food web diversity and structure, and affects predator communities. Theory predicts that strong top-down cascades are less likely to occur as habitat and food web complexity decrease. 2. To examine relationships between habitat complexity and predator effects, we excluded ants from coffee plants in coffee agroecosystems varying in vegetation complexity. Specifically, we studied the effects of eliminating ants on arthropod assemblages, herbivory, damage by the coffee berry borer and coffee yields in four sites differing in management intensification. We also sampled ant assemblages in each management type to see whether changes in ant assemblages relate to any observed changes in top-down effects. 3. Removing ants did not change total arthropod densities, herbivory, coffee berry borer damage or coffee yields. Ants did affect densities of some arthropod orders, but did not affect densities of different feeding groups. The effects of ants on lower trophic levels did not change with coffee management intensity. 4. Diversity and activity of ants on experimental plants did not change with coffee intensification, but the ant species composition differed. 5. Although variation in habitat complexity may affect trophic cascades, manipulating predatory ants across a range of coffee agroecosystems varying in management intensity did not result in differing effects on arthropod assemblages, herbivory, coffee berry borer attack or coffee yields. Thus, there is no clear pattern that top-down effects of ants in coffee agroecosystems intensify or dampen with decreased habitat complexity.


20.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Field-testing ecological and economic benefits of coffee certification programs
Philpott, Stacy M. ; Bichier, Peter (coaut.) ; Rice, Robert (coaut.) ; Greenberg, Russell (coaut.) ;
Contenido en: Conservation Biology Vol. 21, no. 4 (August 2007), p. 975-985 ISSN: 0888-8892
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
44157-10 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Español | Inglés |
Resumen en español

Los agroecosistemas de café son críticos para el éxito de esfuerzos de conservación en América Latina debido a su importancia ecológica y económica. Los programas de certificación de café pueden ofrecer una manera de proteger la biodiversidad y mantener el sustento de los campesinos. Los programas de certificación de café caen en tres categorías distintas, pero no mutuamente excluyentes: orgánico, comercio justo y de sombra. Los resultados de estudios previos demuestran que la certificación de sombra puede beneficiar a la biodiversidad, pero no es claro si la participación de un campesino en cualquier programa de certificación puede proporcionar beneficios tanto ecológicos como económicos. Para estimar el valor de la certificación de café para los esfuerzos de conservación en la región, examinamos aspectos económicos y ecológicos de la producción de café en ocho cooperativas en Chiapas, México, que tenían certificado orgánico, certificado orgánico y comercio justo o no certificado. Comparamos la vegetación y la diversidad de aves y hormigas en las fincas cafetaleras y bosques, y entrevistamos a campesinos para determinar la producción de café, la ganancia bruta por la producción de café y la superficie con producción de café.

Aunque no hay fincas con certificación de sombra en la región de estudio, utilizamos datos de la vegetación para determinar si las cooperativas pudieran calificar para certificación de sombra. Con base en la certificación, no encontramos diferencias en las características de la vegetación, riqueza de especies de aves y hormigas o la fracción de fauna de bosque en las fincas. Los campesinos con certificación orgánica y orgánica y comercio justo tuvieron más tierra bajo cultivo y, en algunos casos, mayores ganancias que los campesinos no certificados. La superficie de producción de café no varió entre tipos de finca. Ninguna cooperativa alcanzó los estándares de certificación de sombra porque sus plantaciones carecían de estratificación vertical, aunque las variables de la vegetación para la certificación de sombra se correlacionaron significativamente con la diversidad de aves y hormigas. Aunque los campesinos del altiplano de Chiapas con certificación orgánica y/o de comercio justo pueden obtener algunos beneficios económicos de su estatus de certificación, sus fincas no protegen tanta biodiversidad como las fincas con certificación de sombra. Trabajar hacia la triple certificación (orgánica, comercio justo y sombra) a nivel de fincas puede reforzar la protección de biodiversidad, incrementar beneficios a los campesinos y llevar hacia estrategias de conservación más exitosas en regiones productoras de café.

Resumen en inglés

Coffee agroecosystems are critical to the success of conservation efforts in Latin America because of their ecological and economic importance. Coffee certification programs may offer one way to protect biodiversity and maintain farmer livelihoods. Established coffee certification programs fall into three distinct, but not mutually exclusive categories: organic, fair trade, and shade. The results of previous studies demonstrate that shade certification can benefit biodiversity, but it remains unclear whether a farmer's participation in any certification program can provide both ecological and economic benefits. To assess the value of coffee certification for conservation efforts in the region, we examined economic and ecological aspects of coffee production for eight coffee cooperatives in Chiapas, Mexico, that were certified organic, certified organic and fair trade, or uncertified. We compared vegetation and ant and bird diversity in coffee farms and forests, and interviewed farmers to determine coffee yield, gross revenue from coffee production, and area in coffee production. Although there are no shade-certified farms in the study region, we used vegetation data to determine whether cooperatives would qualify for shade certification.

We found no differences in vegetation characteristics, ant or bird species richness, or fraction of forest fauna in farms based on certification. Farmers with organic and organic and fair-trade certification had more land under cultivation and in some cases higher revenue than uncertified farmers. Coffee production area did not vary among farm types. No cooperative passed shade-coffee certification standards because the plantations lacked vertical stratification, yet vegetation variables for shade certification significantly correlated with ant and bird diversity. Although farmers in the Chiapas highlands with organic and/or fair-trade certification may reap some economic benefits from their certification status, their farms may not protect as much biodiversity as shade-certified farms. Working toward triple certification (organic, fair trade, and shade) at the farm level may enhance biodiversity protection, increase benefits to farmers, and lead to more successful conservation strategies in coffee-growing regions.


21.
Libro
Stability of tropical rainforest margins: linking ecological, economic and social constraints of land use and conservation / Teja Tscharntke, Christoph Leuschner, Manfred Zeller, Edi Guhardja, Arifuddin Bidin, (eds.)
Disponible en línea: Stability of tropical rainforest margins: linking ecological, economic and social constraints of land use and conservation.
Tscharntke, Teja (editor) (1952-) ; Leuschner, Christoph (editor) ; Zeller, Manfred (editor) ; Guhardja, Edi (editor) ; Bidin, Arifuddin (editor) ;
Berlin, Heidelberg, Germany : Springer-Verlag Berlin Heidelberg , c2007
Disponible en línea
Clasificación: 634.928 / S8
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
ECO010011083 (Disponible)
Disponibles para prestamo: 1

22.
Libro
Arthropod diversity and conservation / edited by David L. Hawksworth and Alan T. Bull
Disponible en línea: Arthropod diversity and conservation.
Hawksworth, David L. (editor) ; Bull, Alan T. (editor) ;
Dordrecht, The Netherlands : Springer , c2006
Disponible en línea
Clasificación: 632.65 / A7
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
ECO010015069 (Disponible)
Disponibles para prestamo: 1

23.
Capítulo de libro
*Solicítelo con su bibliotecario/a
The importance of ants and high-shade management to coffee pollination and fruit weight in Chiapas, Mexico
Philpott, Stacy M. (autora) ; Uno, Shinsuke (coaut.) ; Maldonado, Jorge (autor) ;
Disponible en línea
Contenido en: Arthropod diversity and conservation / edited by David L. Hawksworth and Alan T. Bull Dordrecht, The Netherlands : Springer, c2006 página 473-487 ISBN:1-4020-5203-0 :: 978-1-4020-5203-3
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
60056-10 (Disponible)
Disponibles para prestamo: 1
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Recent reports show importance of pollinators to coffee and importance of ants as pollinators or floral protectors in many systems. Arthropod and pollinator diversity, however, declines with management intensification of coffee (Coffea arabica) agroecosystems. We investigated influences of both flying pollinators and ants on coffee fruit set and fruit weight in one high-shade (high-biodiversity) and one low-shade (low-biodiversity) coffee farm in Chiapas, Mexico through exclusion experiments. Contradictory to previous reports, flying pollinators alone did not affect coffee fruit set or fruit weight. Individual fruit weights, however, were higher on branches with both ants and flying pollinators (1.78 g ± 0.312 (SE)) compared to branches without ants (1.03 ± 0.029) or branches without ants or flying pollinators (1.05 ± 0.049), but only in the high-shade site. Although the mechanisms producing higher fruit weights are unknown, we discuss how ants or ant-flying pollinator interactions under high-shade coffee management may contribute to increased fruit weight and the implications of high-shade management for both sustainable coffee production and biodiversity conservation.


24.
Artículo
*Solicítelo con su bibliotecario/a
The importance of ants and high-shade management to coffee pollination and fruit weight in Chiapas, Mexico
Philpott, Stacy M. (autora) ; Uno, Shinsuke (coaut.) ; Maldonado, Jorge (autor) ;
Disponible en línea
Contenido en: Biodiversity and Conservation Vol. 15, no. 1 (January 2006), p. 487-501 ISSN: 0960-3115
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Recent reports show importance of pollinators to coffee and importance of ants as pollinators or floral protectors in many systems. Arthropod and pollinator diversity, however, declines with management intensification of coffee (Coffea arabica) agroecosystems. We investigated influences of both flying pollinators and ants on coffee fruit set and fruit weight in one high-shade (high-biodiversity) and one low-shade (low-biodiversity) coffee farm in Chiapas, Mexico through exclusion experiments. Contradictory to previous reports, flying pollinators alone did not affect coffee fruit set or fruit weight. Individual fruit weights, however, were higher on branches with both ants and flying pollinators (1.78 g ± 0.312 (SE)) compared to branches without ants (1.03 ± 0.029) or branches without ants or flying pollinators (1.05 ± 0.049), but only in the high-shade site. Although the mechanisms producing higher fruit weights are unknown, we discuss how ants or ant-flying pollinator interactions under high-shade coffee management may contribute to increased fruit weight and the implications of high-shade management for both sustainable coffee production and biodiversity conservation.


25.
Artículo
*En hemeroteca, SIBE-San Cristóbal
Seasonal shift in the foraging niche of a tropical avian resident: resource competition at work?
Jedlicka, Julie A. ; Greenberg, Russell (coaut.) ; Perfecto, Ivette (coaut.) ; Philpott, Stacy M. (coaut) ;
Contenido en: Journal of Tropical Ecology Vol. 22, no. 4 (July 2006 ), p. 419-429 ISSN: 0266-4674
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
B9155 (Disponible)
Disponibles para prestamo: 1
Nota: En hemeroteca, SIBE-San Cristóbal
Resumen en: Español | Inglés |
Resumen en español

Este estudio examinó el comportamiento de forrajeo de un ave residente, Basileuterus rufifrons (RCWA), en una finca de café con sombra en Chiapas, México. A diferencia de muchas aves residentes que usan los agroecosistemas de café con sombra solamante durante una estación, RCWAs no se van a otros hábitats cuando los aves migrantes están presente. El forrajeo de RCWA fue comparado cuando las aves migrantes eran presente (la época seca) y ausente (la época de lluvia). La hipótesis fue que los RCWA exhibirían un cambio de forrajeo con los cambios de estaciones a causa de la competencia de recursos con los migrantes. Observaciones en el docel y el sotobosque en un cafetal muestran que durante la época de lluvia, los RCWAs forrajean igualmente en los dos niveles de vegetación, pero tienen más éxito forrajeando en el docel. Durante la época seca, los migrantes forrajean principalmente en el docel y los RCWAs se mueven al sotobosque donde efectúan 80% de las maniobras de forrajeo. Durante ese tiempo, los RCWAs tuvieron menos éxito forrajeando tanto en el docel como en el sotobosque. Durante la época seca el número de artrópodos bajó entre 47–79% en el docel y entre 4–5% en el sotobosque a causa de la depredación de las aves. En el docel, la disponibilidad de artrópodos grandes (>5 mm en longitud) bajó en un 58% de la época de lluvia a la época seca. Tales reducciones de recursos podrían causar el cambio de lugar a forrajeo observado en RCWA, pero otras explicaciones e hipótesis son discutidas. Pueden ser que este cambio de forrajeo sea común en algunas aves residentes pequeñas que comen artrópodos para evitar la competencia con los migrantes durante la época seca

Resumen en inglés

This study examined the foraging behaviour of a resident bird species, the rufous-capped warbler (RCWA, Basileuterus rufifrons), in a shaded-coffee farm in Chiapas, Mexico. Unlike many resident species that use shaded-coffee agroecosystems seasonally, RCWAs do not move to other habitats when migrants are present. RCWA foraging was compared when migrant birds were present (dry season) and absent (wet season). It was hypothesized that RCWAs would exhibit a seasonal foraging niche shift because of resource competition with migrants. Observations from both the canopy and coffee understorey show that RCWAs foraged almost equally in both vegetative layers during the wet season although they were more successful foraging in the canopy. In the dry season, migrants foraged primarily in the canopy and RCWAs shifted so that 80% of RCWA foraging manoeuvres were in the understorey. At that time RCWAs foraged less successfully in both vegetative layers. Avian predation in the dry season was found to reduce densities of arthropods by 47-79% in the canopy, as opposed to 4-5% in the understorey. In the canopy, availability of large (>5 mm in length) arthropods decreased by 58% from the wet to dry season. Such resource reductions could have caused the RCWA foraging niche shift yet other alternative or additional hypotheses are discussed. Shifts in foraging niche may be a widespread mechanism for some small insectivorous residents to avoid seasonal competition with abundant migrant species.