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10 resultados encontrados para: AUTOR: Huber Sannwald, Elisabeth
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¿Resinar, pastorear y conservar pinares en una reserva de la biósfera? Exploración socioecológica participativa / Marco Braasch, Luis Enrique García Barrios, Neptalí Ramírez Marcial, Héctor Sergio Cortina Villar, Elisabeth Huber-Sannwald, Gabriela García Marmolejo
Braasch, Marco ; García Barrios, Luis Enrique (coaut.) ; Ramírez Marcial, Neptalí (coaut.) (1963-) ; Cortina Villar, Héctor Sergio (coaut.) (1960-) ; Huber Sannwald, Elisabeth (coaut.) ; García Marmolejo, Gabriela (coaut.) ;
San Cristóbal de Las Casas, Chiapas, México : El Colegio de la Frontera Sur , 2018
Clasificación: EE/634.928097275 / R4
SIBE Campeche
ECO040006873 (Disponible)
Disponibles para prestamo: 1
SIBE Chetumal
ECO030008744 (Disponible)
Disponibles para prestamo: 1
SIBE San Cristóbal
ECO010019422 (Disponible) , ECO010019421 (Disponible)
Disponibles para prestamo: 2
SIBE Tapachula
ECO020013760 (Disponible)
Disponibles para prestamo: 1
SIBE Villahermosa
ECO050006407 (Disponible)
Disponibles para prestamo: 1
Índice | Resumen en: Español |
Resumen en español

Este libro describe la construcción de un estudio socioecológico participativo que explora formas para integrar a los actores locales y regionales en el proceso de toma de decisión y aprendizaje colectivo del manejo del bosque a partir de modelación acompañante. Se utiliza como ejemplo la resinación de Pinus oocarpa en dos ejidos de la Reserva de la Biósfera La Sepultura, Chiapas, México. El proyecto de resina combina la conservación de la biodiversidad y el desarrollo social de la población local. La viabilidad de este proyecto a largo plazo está en riesgo debido a la presencia de pastos exóticos que limitan el reclutamiento del pino resinero. Para entender el proceso social y ecológico y construir el modelo basado en agentes TRUE GRASP, se usaron diferentes herramientas metodológicas y técnicas, como información cartográfica, observaciones empíricas ecológicas y sociales, y experimentos de campo. TRUE GRASP es un modelo educativo virtual diseñado para simular las trayectorias futuras del bosque y contribuir así al aprendizaje colectivo de campesinos y otros actores regionales.


1. Antecedentes
1.1. El desafío de las reservas de la biósfera: un espacio para la conservación y el desarrollo social
1.2. El proyecto de resina en la Reserva de la Biósfera La Sepultura
1.3. Beneficios y limitaciones del proyecto de resina
Caja Informativa
Reclutamiento de la especie Pinus oocarpa
Los pastos exóticos invasores
2. El estudio socioecológico participativo
2.1. Historia del bosque abierto y su extensión
2.2. Conocimiento ecológico local y perspectivas futuras de los productores
2.3. Densidad de árboles en relación con la cobertura de suelo
2.4. Los efectos positivos y negativos del ganado en los renuevos
2.5. Los intereses de los actores involucrados en el proyecto de resina
2.6. Modelación de la sucesión del bosque abierto en resinación
2.7. El proceso de toma de decisión colectivo

*Solicítelo con su bibliotecario/a
TRUE GRASP: actors visualize and explore hidden limitations of an apparent win-win land management strategy in a MAB reserve
Braasch, Marco ; García Barrios, Luis Enrique (coaut.) ; Cortina Villar, Héctor Sergio (coaut.) (1960-) ; Huber Sannwald, Elisabeth (coaut.) ; Ramírez Marcial, Neptalí (coaut.) (1963-) ;
Contenido en: Environmental Modelling & Software Vol. 105 (July 2018), p. 153-170 ISSN: 1364-8152
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Win-win solutions might be short-lived. Government permission for smallholder farmers to extract and sell resin from a pine savanna biosphere-reserve in Mexico has settled a long dispute among different stakeholders in the short-term; however, forest production and conservation beyond 20 years are compromised due to low pine recruitment caused by competition with exotic grasses. Grass control practiced by farmers through grazing and fire has previously been discouraged by conservation authorities, which inadvertently limits long-term pine conservation and use. We describe the participatory design, rationale and simulation attributes of an educational, interactive, agent-based model that explores suites of management options and their economic and ecological outputs. We present and analyze the outcomes of four simulation workshops, where farmers and external-actors better grasped the complex ecological interactions involved in conserving and using pines in grazed pine savanna with exotic grasses, and discussed these findings with a long-term vision and tradeoff analysis approach.

- Artículo con arbitraje
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Can cattle grazing substitute fire for maintaining appreciated pine savannas at the frontier of a montane forest biosphere-reserve?
Braasch, Marco ; García Barrios, Luis Enrique (coaut.) ; Ramírez Marcial, Neptalí (coaut.) (1963-) ; Huber Sannwald, Elisabeth (coaut.) ; Cortina Villar, Héctor Sergio (coaut.) (1960-) ;
Contenido en: Agriculture, Ecosystems & Environment Vol. 250 (December 2017), p. 59–7 ISSN: 0167-8809
Nota: Solicítelo con su bibliotecario/a
Resumen en: Inglés |
Resumen en inglés

Human induced savannas in subtropical regions are often favored by small-holder farmers for livestock production and extraction of wood or non-wood products. Frequent burning and grazing are required to maintain the savanna vegetation structure. However, in conservation areas, fire suppression is promoted to avoid wildfires; whereas domestic livestock grazing is considered a strong interfering factor for tree establishment, due to trampling and browsing. In tropical forests which were converted to savannas, competitive exotic grasses have often replaced the native grasses. Where exotic grasses are present, aboveground biomass accumulation and thus man-induced fire risk are high and potentially undermine tree recruitment. On the long-term, the savanna state may shift into a grass-dominated state with little tree cover, generating unfavorable conditions from a livelihood perspective. We examined this problem in a human-induced pine savanna in the La Sepultura Biosphere Reserve in Chiapas, Mexico. Smallholder farmers highly valued this savanna for both livestock production and resin extraction from the fire resistant pine Pinus oocarpa. However, fire suppression and the presence of exotic grasses are reducing the tree recruitment. The main research question was to what degree can cattle grazing replace fire in its role of biomass removal and thereby stimulate pine recruitment and maintain the desired savanna state. We determined current savanna extension in the region and interviewed farmers to reconstruct past savannazation processes and expansion of exotic grasses. We related adult species-specific tree density to the herbaceous-grass cover, and pine and oak seedling and sapling densities to understory vegetation cover, canopy closure, and cattle grazing history. Finally, a field experiment was conducted to examine the effects of livestock grazing on survival and growth of planted pine saplings.

The savanna currently covers 20% of the study site; it is the result of past slash-and-burn agriculture and selective logging, which have favored the expansion of several exotic grass species. In savannas where exotic grasses are abundant, sapling density was lower compared to sites with a native grass cover. While livestock grazing seemed to increase pine seedling density likely as a consequence of reduced grass cover, pine sapling survival however, was significantly reduced by livestock trampling. By seeking a balance between the livestock’s benefits and adverse effects on pine recruitment, farmers may develop an integrated management system adapted to their specific biotic rangeland conditions. It should allow forage production, while controlling the negative effects of exotic grasses on pine recruitment, thus maintaining a productive pine savanna system.

Resumen en: Inglés |
Resumen en inglés

While semiarid forests frequently colonize rocky substrates, knowledge is scarce on how roots garner resources in these extreme habitats. The Sierra San Miguelito Volcanic Complex in central Mexico exhibits shallow soils and impermeable rhyolitic-rock outcrops, which impede water movement and root placement beyond the soil matrix. However, rock fractures, exfoliated rocks and soil pockets potentially permit downward water percolation and root growth. With ground-penetrating radar (GPR) and electrical resistivity tomography (ERT), two geophysical methods advocated by Jayawickreme et al. (2014) to advance root ecology, we advanced in the method development studying root and water distribution in shallow rocky soils and rock fractures in a semiarid forest. We calibrated geophysical images with in situ root measurements, and then extrapolated root distribution over larger areas. Using GPR shielded antennas, we identified both fine and coarse pine and oak roots from 0.6 to 7.5cm diameter at different depths into either soil or rock fractures. We also detected, trees anchoring their trunks using coarse roots underneath rock outcroppings. With ERT, we tracked monthly changes in humidity at the soil–bedrock interface, which clearly explained spatial root distribution of both tree species. Geophysical methods have enormous potential in elucidating root ecology. More interdisciplinary research could advance our understanding in belowground ecological niche functions and their role in forest ecohydrology and productivity.

Tesis - Doctorado
Vacas, pinos resineros y pastos exóticos; exploración participativa de un balance socio-ecológico con experimentos y modelos / Marco Braasch
Braasch, Marco ; García Barrios, Luis Enrique (director) ; Ramírez Marcial, Neptalí (asesor) (1963-) ; Cortina Villar, Héctor Sergio (asesor) (1960-) ; Huber Sannwald, Elisabeth (asesor) ;
San Cristóbal de Las Casas, Chiapas, México : El Colegio de la Frontera Sur , 2017
Clasificación: TE/634.928097275 / B7
Bibliotecas: San Cristóbal
SIBE San Cristóbal
ECO010019411 (Disponible)
Disponibles para prestamo: 1
Índice | Resumen en: Español |
Resumen en español

En la resinación de Pinus oocarpa se concilió la conservación y aprovechamiento de recursos naturales en la Reserva de la Biosfera la Sepultura, Chiapas, México. La persistencia de este proyecto depende del constante reclutamiento de este pino, que actualmente está limitado por la presencia de pastos exóticos, favorecidos por un manejo conservacionista, no quemar y no permitir el pastoreo. Ignorar la ausencia de renuevos en el presente, amenaza la viabilidad del proyecto de resina a largo plazo. Los campesinos proponen la ganadería extensiva como una forma de controlar el crecimiento de los pastos. Sin embargo, no es clara la magnitud de los beneficios y daños que tiene el pastoreo en la estabilidad de este sistema socio-ecológico, como tampoco se conoce la aceptación de esta práctica por otros actores regionales involucrados en el proyecto. El objetivo central fue determinar las condiciones socio-ecológicas necesarias para reclutar nuevas cohortes de P. oocarpa en un bosque abierto de pino, tipo vegetación sabanoide, apreciada para uso de resina y pastoreo extensivo. Mediante encuestas se determinó el conocimiento ecológico local y se describió la historia de la sabana. La extensión y ecología de la sabana fue determinada a través de técnicas de sensores remotos y observaciones ecológicas empíricas, y mediante un experimento se evaluaron los efectos directos e indirectos de la ganadería sobre plántulas de pino transplantadas. Con base de este conocimiento socio-ecológico se construyó, parametrizó y calibró un modelo basado en agentes TRUE GRASP, que se aplicó en un taller participativo para estudiar los procesos de toma de decisión entre actores. Se encontró que la ganadería es un manejo potencial viable para mantener la resinación a largo plazo.

Sin embargo, para ser aceptado por diferentes actores, se requiere encontrar un balance entre daño y beneficio que exploraron campesinos y actores regionales en conjunto con simulaciones en TRUE GRASP.


Palabras claves
Capítulo I
Objetivos específicos
Organización de la tesis
Capítulo II
Can cattle grazing substitute fire for maintaining appreciated pine savannas at the frontier of a montane forest biosphere-reserve?
1 Introduction
2 Study area and methods
2.1 Study area
2.2 Methods
2.2.1 Actual spatial extent of pine savanna
2.2.2 Land use history and drivers of savannization
2.2.3 Savanna tree species composition and diameter at breast height class distribution
2.2.4 Influence of grass type and grazing on sapling density
2.2.5 Influence of vegetation cover on seedling density
2.2.6 Direct and indirect effects of livestock on pine sapling growth and survival in exotic and native grass plots
2.3 Data analysis
3 Results
3.1 Current spatial extent of pine savanna
3.2 Land use history and drivers of savannization
3.3 Savanna tree species composition and DBH class distribution
3.4 Influence of grass type and grazing on sapling density
3.5 Influence of vegetation cover on seedling density
3.6 Direct and indirect effects of livestock on pine sapling growth and survival in exotic and native grass plots
3.6.1 Soil conditions, soil temperature and soil humidity in the experimental plots
3.6.2 Grass growth and aboveground biomass production
3.6.3 Survival of pine saplings in response to biomass removal treatments and grass species
3.6.4 Growth of pine saplings in experimental plots
4 Discussion
5 Conclusions
Appendix A
Supplementary data
Capítulo III
TRUE GRASP: Actors visualize and explore hidden limitations of an apparent win-win land management strategy in a MAB Reserve
1 Introduction
2 Methods
2.1 Study area
2.2 Extensive surveys with resin producers, main topics and analyses
2.3. The TRUE GRASP agent based model

2.3.1. Virtual world and components
2.3.2 Management practices to control exotic grasses and pine needle litter
2.3.3 Model parameterization and calibration
2.4 Single- and multi Actor Workshop
2.4.1 Preliminary surveys
2.4.2 Single actor workshops
2.4.3 Multi-actor joint workshop
3 Results
3.1 Farmer interviews to explore local ecological knowledge
3.2 Agent based model capabilities
3.3 ABM-supported scenario exploration Workshops:
3.3.1 Pre-agent based model surveys and tests
3.3.2 Farmers´ and externals´ understanding and validation of the agent based model
3.3.3 Farmers´ and externals´ management parameter explorations in search of pre-established ecological-economical goals
3.3.4 The “two-brother” exercise
3.3.5 Reflection meetings (farmer vs external separate reflection meetings)
3.3.6 Multi-actor joint ABM exploration
3.3.7 Multi-actor meeting to discuss decision tree
4 Discussion and Conclusion
Pre-modelling interviews
Model Development
Pre-simulation Quizzes
Learning, trusting and using TRUE GRASP
User´s evaluation of TRUE GRASP
Multi-actor exercises and deliberation
Cited literature
Appendix A
TRUE GRASP: Overview, Design concepts, and Details (ODD)
Appendix B
Sensitivity analisis
Capítulo IV
Conclusión general
Literatura Citada
Anexo A:
Resumen de los resultados de las entrevistas con 52 campesinos en California y Tres Picos durante 2016
Anexo B
Cuestionario de las entrevistas y material que se usó para las encuestas
Anexo C
Precipitación y temperatura del área de estudio
Anexo D
Caracterización de las parcelas experimentales

- Artículo con arbitraje
Landscape composition influences abundance patterns and habitat use of three ungulate species in fragmented secondary deciduous tropical forests, Mexico
García Marmolejo, Gabriela ; Chapa Vargas, Leonardo (coaut.) ; Weber, Manuel (coaut.) ; Huber Sannwald, Elisabeth (coaut.) ;
Contenido en: Global Ecology and Conservation Vol. 3 (January 2015), p. 744–755 ISSN: 2351-9894
Resumen en: Inglés |
Resumen en inglés

Secondary forests are extensive in the tropics. Currently, these plant communities are the available habitats for wildlife and in the future they will possibly be some of the most wide-spread ecosystems world-wide. To understand the potential role of secondary forests for wildlife conservation, three ungulate species were studied: Mazama temama, Odocoileus virginianus and Pecari tajacu. We analyzed their relative abundance and habitat use at two spatial scales: (1) Local, where three different successional stages of tropical deciduous forest were compared, and (2) Landscape, where available habitats were compared in terms of landscape composition (proportion of forests, pastures and croplands within 113 ha). To determine the most important habitat-related environmental factors influencing the Sign Encounter Rate (SER) of the three ungulate species, 11 physical, anthropogenic and vegetation variables were simultaneously analyzed through model selection using Akaike’s Information Criterion. We found, that P. tajacu and O. virginianus mainly used early successional stages, while M. temama used all successional stages in similar proportions. The latter species, however, used early vegetation stages only when they were located in landscapes mainly covered by forest (97%). P. tajacu and O. virginianus also selected landscapes covered essentially by forests, although they required smaller percentages of forest (86%). All ungulate species avoided landscape fragments covered by pastures. For all three species, landscape composition and human activities were the variables that best explained SER. We concluded that landscape is the fundamental scale for ungulate management, and that secondary forests are potentially important landscape elements for ungulate conservation.

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

Over the past 20 years, the multifunctionality of tropical mountain rural landscapes has been encouraged to enhance the provision of numerous commodities, as well as ecological and cultural services. However, globalization and neoliberal policies have boosted agricultural production for global markets and simultaneously marginalized fundamental rural activities related to self-supply agriculture. This trend has modified smallholder livelihoods from being mostly agricultural to becoming increasingly wage-labor oriented. This shift in household income feeds back to land use configuration and landscape function. We examined origins, development and current states of farmer livelihoods and associated land use and cover changes that occurred in a tropical watershed landscape of the Huasteca Potosina in Mexico between 1970 and 2009. For this purpose, we adopted the Drylands Development Paradigm (DDP) as our analytical framework (Reynolds et al., 2007). Based on aerial photographs and interviews applied to farmers and key stakeholders, we identified local, regional, national and international socio-economic and biophysical drivers that led to current livelihood diversification in several communities sharing the same watershed, and the extent and rate of land use change that has occurred over the past 40 years. We found an increasingly fragmented landscape with a diverse mosaic of land use types (citrus, sugarcane, milpa and secondary forests) yet increasingly dominated by citrus plantations.

This reflects an intergeneration livelihood transition towards land use decisions driven by the interaction of diverse and contrasting rural development policies, changing markets, price fluctuations and extreme climatic events. We suggest that the diversity of livelihood strategies and land use types is dynamic and continuously in transition; this creates a complex and changing landscape. The watershed landscape has responded to global markets at the cost of local needs, knowledge systems and social networks. Thus, landscape multifunctionality, preservation of ecosystem services and human well being could be at stake under current trends of globalization and global environmental change.

Resumen en: Inglés |
Resumen en inglés

Development of sustainable agricultural production systems in the tropics is challenging in part because the local and external conditions that affect sustainability are constantly in flux. The Quesungual agroforestry system (QSMAS) was developed in response to these changing conditions. The history and potential future of the QSMAS provide an opportunity to consider the factors affecting small-scale agricultural production systems on marginal lands throughout the world. We evaluated the QSMAS in Honduras in the context of the five principles of the Drylands Development Paradigm (DDP) during three periods: pre-QSMAS, QSMAS adoption and the future. The first two periods provided lessons that could be relevant to other regions. The QSMAS system in Honduras must continue to evolve, if long-term benefits are to be realized. We conclude that while the DDP was a useful framework for systematically identifying the critical drivers and processes determining the sustainability of QSMAS in Honduras, it is ultimately no more able to predict the future than the collective knowledge of those who choose to apply it. The DDP, however, can facilitate the integration and application of knowledge.


- Capítulo de libro con arbitraje