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617 resultados encontrados para: TEMA: Bosques tropicales
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1.
Libro
Ecology of epiphytes and epiphyte communities in montane rain forests, Colombia / Jan Hendrik Diederik Wolf
Wolf, Jan Hendrik Diederik ;
[The Netherlands] : [University of Amsterdam, Department of Systematics, Evolution and Palaeobiology] , s.f.
Clasificación: 584.09861 / W6
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
ECO010008265 (Disponible)
Disponibles para prestamo: 1

2.
Libro
Programa de acción forestal tropical PROAFT
México. Secretaría de Agricultura y Recursos Hidráulicos. Subsecretaría Forestal y de Fauna Silvestre ;
México : Secretaría de Agricultura y Recursos Hidráulicos , s. f
Clasificación: F/634.928 / M4
Bibliotecas: San Cristóbal
Cerrar
SIBE San Cristóbal
SAF001677 (Disponible)
Disponibles para prestamo: 1

3.
- Artículo con arbitraje
*Solicítelo con su bibliotecario/a
Management strategies, silvopastoral practices and socioecological drivers in traditional livestock systems in tropical dry forests: an integrated analysis
Sánchez Romero, Rosa (autora) ; Balvanera, Patricia (autora) ; Castillo Álvarez, Alicia (autora) ; Mora Ardila, Francisco (autor) ; García Barrios, Luis Enrique (autor) ; González Esquivel, Carlos Ernesto (autor) ;
Disponible en línea
Contenido en: Forest Ecology and Management Volumen 479, artículo número 118506 (January 2021), páginas 1-10 ISSN: 0378-1127
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Understanding traditional livestock management is essential in the design of more sustainable systems, given the forest loss associated to the growing demand for meat. In Latin America, where extensive livestock production is increasing, along with tropical dry forest (TDF) transformation, the role of small holders is critical for designing more sustainable management practices. This study is an integrated socioecological analysis of traditional livestock systems in a region with TDF in Mexico. The objectives were to: a) characterise the historical development and current state of livestock systems and silvopastoral practices, b) define the management strategies and their impacts on forests, and c) identify the regional and local socioecological drivers that influence decision- making processes in livestock and forest management. In-depth interviews were carried out to 32 cattle farmers and analysed using a qualitative-interpretative approach which included multivariate and narrative analyses. Three historical stages (colonization, promotion of livestock and forest conservation) had a strong impact in the development and current state of livestock systems. Access to natural and economic resources and proportion of plant cover (grassland/forest) were essential in defining four groups of management strategies.

The main regional drivers favouring or restricting production include climate, native vegetation, markets and public policies; at the local scale, socioecological factors, such as water availability, native vegetation, economic assets, local knowledge and their interactions determine heterogeneity in management strategies, decision-making processes and their impacts on forests. Adaptive management of livestock and forests in a context of limited economic resources has allowed the conservation of forest areas and the use of silvopastoral practices with local tree species. The integrated socio-ecological approach and the use of mixed methods allowed a better understanding of drivers and their interrelationships, the local knowledge, objectives and perceptions of farmers in the decision-making processes regarding livestock and forest management. Perspectives of farmers on resource use can contribute to the design of more effective and inclusive policies for sustainable livestock systems in the dry tropics.


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Resumen en: Español |
Resumen en español

Here, we use 30 long-term, high-resolution palaeoecological records from Mexico, Central and South America to address two hypotheses regarding possible drivers of resilience in tropical forests as measured in terms of recovery rates from previous disturbances. First, we hypothesize that faster recovery rates are associated with regions of higher biodiversity, as suggested by the insurance hypothesis. And second, that resilience is due to intrinsic abiotic factors that are location specific, thus regions presently displaying resilience in terms of persistence to current climatic disturbances should also show higher recovery rates in the past. To test these hypotheses, we applied a threshold approach to identify past disturbances to forests within each sequence. We then compared the recovery rates to these events with pollen richness before the event. We also compared recovery rates of each site with a measure of present resilience in the region as demonstrated by measuring global vegetation persistence to climatic perturbations using satellite imagery. Preliminary results indeed show a positive relationship between pre-disturbance taxonomic richness and faster recovery rates. However, there is less evidence to support the concept that resilience is intrinsic to a region; patterns of resilience apparent in ecosystems presently are not necessarily conservative through time.


5.
Artículo
PDF
Resumen en: Inglés |
Resumen en inglés

Background: Reliable information about the spatial distribution of aboveground biomass (AGB) in tropical forests is fundamental for climate change mitigation and for maintaining carbon stocks. Recent AGB maps at continental and national scales have shown large uncertainties, particularly in tropical areas with high AGB values. Errors in AGB maps are linked to the quality of plot data used to calibrate remote sensing products, and the ability of radar data to map high AGB forest. Here we suggest an approach to improve the accuracy of AGB maps and test this approach with a case study of the tropical forests of the Yucatan peninsula, where the accuracy of AGB mapping is lower than other forest types in Mexico. To reduce the errors in field data, National Forest Inventory (NFI) plots were corrected to consider small trees. Temporal differences between NFI plots and imagery acquisition were addressed by considering biomass changes over time. To overcome issues related to saturation of radar backscatter, we incorporate radar texture metrics and climate data to improve the accuracy of AGB maps. Finally, we increased the number of sampling plots using biomass estimates derived from LiDAR data to assess if increasing sample size could improve the accuracy of AGB estimates.

Results: Correcting NFI plot data for both small trees and temporal differences between field and remotely sensed measurements reduced the relative error of biomass estimates by 12.2%. Using a machine learning algorithm, Random Forest, with corrected field plot data, backscatter and surface texture from the L‑band synthetic aperture radar (PALSAR) installed on the on the Advanced Land Observing Satellite‑1 (ALOS), and climatic water deficit data improved the accuracy of the maps obtained in this study as compared to previous studies (R²=0.44 vs R²= 0.32). However, using sample plots derived from LiDAR data to increase sample size did not improve accuracy of AGB maps (R²= 0.26). Conclusions: This study reveals that the suggested approach has the potential to improve AGB maps of tropical dry forests and shows predictors of AGB that should be considered in future studies. Our results highlight the importance of using ecological knowledge to correct errors associated with both the plot‑level biomass estimates and the mis‑match between field and remotely sensed data.


6.
Artículo
Mapping disturbance from selective logging in tropical forests of the Yucatan Peninsula, Mexico
Hernández Gómez, Irving Uriel (autor) ; Vázquez Luna, Dinora (autora) ; Cerdán Cabrera, Carlos Roberto (autor) ; Navarro Martínez, María Angélica (autora) ; Ellis, Edward Alan (autor) ;
Disponible en línea
Contenido en: Tropical and Subtropical Agroecosystems Volumen 23, número 1 (2020), páginas 143-152 ISSN: 1870-0462
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Resumen en: Español | Inglés |
Resumen en español

El mapeo de los impactos de la tala selectiva en la Península de Yucatán es importante para lograr la reducción de las emisiones de carbono y los objetivos de conservación de la biodiversidad. Objetivo. Evaluar la efectividad de la aplicación de técnicas de teledetección mediante el uso de imágenes LANDSAT 8 OLI para detectar la perturbación del bosque tropical a partir de la extracción de madera en cuatro bosques con manejo comunitario (ejidos). Además, evaluamos las diferencias entre ellos en términos de implementación de manejo forestal mejorado (IFM) y prácticas de aprovechamiento de impacto reducido (RIL). Metodología. Se calcularon los índices de vegetación y se realizó la clasificación de la cubierta forestal para hacer un mapa de las zonas taladas y no taladas y las perturbaciones específicas del aprovechamiento (por ejemplo, claros por la tala de árboles, carriles de arrastre, caminos forestales y áreas de acopio de madera) en las áreas de corta anual de 2014. Las evaluaciones de precisión se realizaron en función de los puntos de validación colectados en el campo después del aprovechamiento. Resultados. Encontramos que el 75% de las clasificaciones binarias (áreas impactadas y no impactadas) tenían precisiones globales medias superiores al 60%, lo que representa una precisión aceptable (40 a 70%), aunque el mapeo de las perturbaciones específicas de la cosecha tuvo poca precisión (<40%). Los índices de vegetación que obtuvieron los mejores resultados fueron el índice de vegetación de diferencia normalizada (NDVI), Tasseled Cap Greenness y Tasseled Cap Wetness. Los ejidos que aplicaron IFM y RIL impactaron un porcentaje menor de sus áreas de corta y menos área de bosque por metro cúbico de madera extraída, a pesar de intensidades de tala similares o mayores que los ejidos sin prácticas mejoradas.

Implicaciones. El monitoreo del impacto por la tala selectiva es importante para mejorar el manejo forestal y la certificación de sostenibilidad. Conclusiones. El mapeo y el monitoreo de los impactos de la tala selectiva por gestores y técnicos forestales se puede realizar de manera costo-efectiva utilizando imágenes LANDSAT 8, aunque la precisión se puede mejorar con imágenes de alta resolución.

Resumen en inglés

Background. Mapping selective logging impacts on the Yucatan Peninsula is important to pursuing carbon emissions reduction and biodiversity conservation goals. Objective. To evaluate the effectiveness of applying remote sensing techniques using LANDSAT 8 OLI imagery to detect tropical forest disturbance from timber harvesting in four communally managed forests (ejidos). We further assess differences among them in terms of implementing improved forest management (IFM) and reduced impact logging (RIL). Methodology. Vegetation indices were calculated, and forest cover classification was performed to map logged and unlogged forest and specific harvest disturbances (e.g. felling gaps, skid trails, logging roads and log landings) in annual cutting areas of 2014. Accuracy assessments were conducted based on validation points collected in the field after logging. Results. We found that 75% of the binary classifications (logged and unlogged forest) had mean overall accuracies greater than 60%, representing a fair (40 to 70%) accuracy, although mapping of specific harvesting disturbances had poor accuracy (<40%). Vegetation indices that performed the best were normalized vegetation index (NDVI), Tasseled Cap Greenness and Tasseled Cap Wetness. Ejidos that applied IFM and RIL impacted a smaller percentage of their cutting areas and less area of forest per cubic meter of timber extracted, despite similar or higher logging intensities than ejidos without improved practices. Implication. Monitoring selective logging disturbance is important to improved forest management and certification of sustainability. Conclusion. Mapping and monitoring impacts from selective logging by forest managers and technicians can be performed in a cost-efficient manner using LANDSAT 8 images, although accuracy could be improved with higher resolution imagery.


7.
Tesis - Maestría
*En proceso técnico. Solicítelo con el bibliotecario de SIBE-Campeche
Bacterias asociadas a árboles tropicales en zonas de recuperación de un disturbio antrópico / Ángel Antonio Becerra Lucio
Becerra Lucio, Ángel Antonio (0000-0002-9620-0829) ; Peña Ramírez, Yuri Jorge Jesús (Director) ; Chávez Bárcenas, Ana Tztzqui (Codirectora) ; Machkour M'Rabet, Salima (Asesora) ;
Lerma, Campeche, México : El Colegio de la Frontera Sur , 2019
Clasificación: TE/579.17097264 / B4
Bibliotecas: Campeche
Cerrar
SIBE Campeche
ECO040006967 (Disponible)
Disponibles para prestamo: 1
Nota: En proceso técnico. Solicítelo con el bibliotecario de SIBE-Campeche
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8.
- Artículo con arbitraje
*Solicítelo con su bibliotecario/a
Carbon storage in a silvopastoral system compared to that in a deciduous dry forest in Michoacán, Mexico
López Santiago, José Germain (autor) ; Casanova Lugo, Fernando (autor) ; Villanueva López, Gilberto (autor) ; Díaz Echeverria, Víctor Francisco (autor) ; Solorio Sánchez, Francisco Javier (autor) ; Martínez Zurimendi, Pablo (autor) ; Aryal, Deb Raj (autor) ; Chay Canul, Alfonso Juventino (autor) ;
Disponible en línea
Contenido en: Agroforestry Systems Vol. 93, no. 1 (Fabruary 2019), p. 199-211 ISSN: 0167-4366
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Resumen en: Inglés |
Resumen en inglés

Livestock production in the tropics contributes significantly to global greenhouse gas emissions, so better understanding the role of silvopastoral systems (SPS) in mitigating such emissions is necessary. The aim of this study was to evaluate the amounts of carbon stored in the biomass and soil organic carbon (SOC) components of a Leucaena leucocephala cum Panicum maximum silvopasture system (SPS) compared to a deciduous tropical forest (DTF), and a grass monoculture (GM) in Michoacán, Mexico. The above- and below-ground biomass were measured by destructive sampling in the SPS and GM, while previously reported allometric equations were used to quantify biomass stocks in the DTF. The SOC concentration up to 30 cm was determined by dry combustion method. The SPS and DTF contained more aboveground biomass (41.8 ± 3.30 and 36.7 ± 5.72 Mg DM ha−¹) compared to GM (8.0 ± 0.76 Mg DM ha−¹). However, the SPS exhibited greater belowground biomass (16.4 ± 1.95 Mg DM ha−¹) than the other systems. The DTF had the highest SOC fraction in all depth classes with values ranging from 3.1 ± 0.07% to 3.7 ± 0.06%, respectively, compared to the other systems. The total carbon stocks in SPS was similar to DTF (120.7 ± 10.97 vs. 120.9 ± 6.38 Mg C ha−¹) but was significantly higher than GM (78.2 ± 8.41 Mg C ha−¹). In dry tropical conditions, SPS displays enormous potential for increasing biomass and soil carbon stocks compared to the GM and can thus be used as a greenhouse gas mitigation strategy in livestock production systems.


9.
Artículo
Combining LiDAR data and airborne imagery of very high resolution to improve aboveground biomass estimates in tropical dry forests
Reyes Palomeque, Gabriela (autora) ; Manuel Dupuy, Juan (autor) ; Johnson, Kristofer D. (autor) ; Castillo Santiago, Miguel Ángel (autor) ; Hernández Stefanoni, José Luis (autor) ;
Disponible en línea
Contenido en: Forestry An International Journal of Forest Research Volume 92, número 5 (October 2019), p. 599–615 ISSN: 1464-3626
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Resumen en: Inglés |
Resumen en inglés

Knowledge of the spatial distribution of aboveground biomass (AGB) is crucial to guide forest conservation and management to maintain carbon stocks. LiDAR has been highly successful for this purpose, but has limited availability. Very-high resolution (<1 m) orthophotos can also be used to estimate AGB because they allow a fine distinction of forest canopy grain. We evaluated the separate and joint performance of orthophotos and LiDAR data to estimate AGB in two types of tropical dry forests in the Yucatan Peninsula. Woody plants were surveyed in twenty 0.1 ha plots in a semideciduous forest at Kaxil Kiuic Biocultural Reserve (RBKK) and 28 plots in a semievergreen forest at Felipe Carrillo Puerto (FCP). We fitted three regression models: one based on LiDAR data, another based on orthophoto variables calculated for forest canopy and canopy opening fractions, and a third model that combined both sets of variables. Variation in AGB was decomposed into LiDAR, orthophotos and joint components using variation-partitioning analyses. In FCP, regression models using LiDAR data only showed higher fit (R2 = 0.82) than orthophoto variables only (R² = 0.70). In contrast, orthophotos had a slightly higher fit (R² = 0.91) than LiDAR (R2 = 0.88) in RBKK, because orthophoto variables characterize very well the horizontal structure of canopies on this site. The model that combined both data sets showed a better fit (R2 = 0.85) only in FCP, which has a more complex forest structure. The largest percentage of AGB variation (88 per cent in RBKK and 67 per cent in FCP) was explained by the joint contribution of LiDAR and orthophotos. We conclude that both LiDAR and orthophotos provide accurate estimation of AGB, but their relative performance varies with forest type and structural complexity. Combining the two sets of variables can further improve the accuracy of AGB estimation, particularly in forests with complex vegeta


10.
Artículo
Conocimiento tradicional medicinal de árboles tropicales y su valor para la restauración de bosques tropicales
García Flores, Juana (autora) ; González Espinosa, Mario (autor) (1950-) ; Lindig Cisneros, Roberto (autor) ; Casas Fernández, Alejandro (autor) ;
Contenido en: Botanical Sciences Vol. 97, no. 3 (2019), p. 336–354 ISSN: 2007-4476
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Resumen en: Español | Inglés |
Resumen en español

Antecedentes. El conocimiento tradicional medicinal (CTM) permite atender necesidades de salud de 80 % de la población mundial y puede servir como guía para recuperar biodiversidad en regiones tropicales, ya que la mayor diversidad de plantas medicinales incluye especies tropicales. Pregunta. ¿Provee el CTM una estrategia para identificar especies arbóreas que por su importancia cultural y ecológica conviene emplear en proyectos de restauración de bosques tropicales? Sitio y fechas . El estudio se realizó en 2015, en cuatro comunidades rurales de la región Sierra de Tabasco, México. Métodos. Con base en revisión bibliográfica se obtuvo un listado de referencia sobre árboles medicinales nativos de la región. Efectuamos entrevistas semiestructuradas y un taller participativo en cada comunidad; se documentaron usos medicinales, enfermedades recurrentes, listados libres de especies medicinales y aquellas con prioridad para emplearse en acciones de restauración. Calculamos índices de riqueza de conocimiento ( IRC ) y de significancia cultural ( ICS ). Resultados. Registramos 45 especies arbóreas medicinales nativas. Las mujeres adultas y ancianas mostraron el mayor CTM. Las principales enfermedades fueron gastrointestinales (93-97 %) y las asociadas a dolores y fiebre (67-97 %), tratadas con 13 y 16 especies, respectivamente. El IRC reflejó un conocimiento promedio menor a 50 %. Gliricidia sepium, Bursera simaruba y Piper auritum tuvieron valores altos de ICS, mientras que Brosimum alicastrum, Ceiba pentandra y Castilla elastica mostraron valores bajos y son consideradas con alta prioridad para la restauración forestal. Conclusiones. El CTM es importante para seleccionar especies arbóreas en la restauración de los bosques tropicales del sureste de México.

Resumen en inglés

Background: Traditional medicinal knowledge (TMK) accounts for attending nearly 80 % of the worldwide needs of health and may guide biodiversity restoration efforts in tropical regions where the greatest diversity of medicinal plants occurs. Questions: Can TMK become a strategy to be used in identifying medicinal tree species, with both cultural and ecological importance, that should be considered in tropical forest restoration actions? Study site and dates: The study was conducted during 2015 in four communities of the Sierra region of southern Tabasco, Mexico. Methods: We obtained from the literature a checklist of medicinal trees native to the study region. We conducted semi-structured interviews and a workshop in each community; we obtained ethnobotanical data about the most common illnesses and the most frequently used plant species for attending them. We identified priority species for forest restoration, and calculated indexes of knowledge richness (IKR) and cultural significance (ICS). Results: We recorded a total of 45 tree species. Adult and elder women showed the highest TMK. The main illnesses detected were gastrointestinal (93-97 %) and those related with pain and fever (67-97 %), which were treated with 13 and 16 species, respectively. On average, the IKR was less than 50 % of all species recorded. Gliricidia sepium, Bursera simaruba and Piper auritum had high ICS values, while Brosimum alicastrum, Ceiba pentandra and Castilla elastica had low values and are considered high priority for forest restoration actions. Conclusions: TMK is important to select tree species in tropical forest restoration actions in southeastern Mexico.