El impacto de la violencia en los flujos migratorios procedentes de Guatemala

Thania Berenice Hernández Alarcón (2021, [Tesis de maestría])

Con este trabajo buscamos entender cómo la violencia en el lugar de origen de una persona puede motivar su decisión de migrar. La aproximación teórica al fenómeno de la migración sugiere que la provisión relativa de bienes públicos es un factor en el análisis costo beneficio mediante el cual el agente evalúa la rentabilidad de la migración. Desde esta perspectiva, la búsqueda de beneficios pecuniarios, como un mayor salario, es compatible con la búsqueda de beneficios no pecuniarios, como mayores niveles de seguridad. Nos interesamos por evaluar lo anterior para el caso de Guatemala. Sirviéndonos de la variación trimestral de trecientos veintinueve municipios en una ventana de once años buscamos evidencia de que la tasa de migración de personas de origen guatemalteco que buscan empleo en México o Estados Unidos se correlaciona de manera positiva con la tasa de homicidios en sus municipios de origen. Nuestros resultados sugieren que esto se cumple y que aumentos en los niveles de violencia homicida pueden propiciar desplazamientos laborales.

Guatemala -- Emigration and immigration -- Effect of violence on -- Econometric models United States -- Emigration and immigration -- Econometric models. CIENCIAS SOCIALES CIENCIAS SOCIALES

Do provisioning ecosystem services change along gradients of increasing agricultural production?

Ronju Ahammad Stephanie Tomscha Sarah Gergel Frédéric Baudron Jean-Yves Duriaux Chavarría Samson Foli Dominic Rowland Josh Van Vianen Terence Sunderland (2024, [Artículo])

Context: Increasing agricultural production shapes the flow of ecosystem services (ES), including provisioning services that support the livelihoods and nutrition of people in tropical developing countries. Although our broad understanding of the social-ecological consequences of agricultural intensification is growing, how it impacts provisioning ES is still unknown. Objectives: We examined the household use of provisioning ES across a gradient of increasing agricultural production in seven tropical countries (Bangladesh, Burkina Faso, Cameroon, Ethiopia, Indonesia, Nicaragua and Zambia). We answered two overarching questions: (1) does the use of provisioning ES differ along gradients of agriculture production ranging from zones of subsistence to moderate and to high agriculture production? and (2) are there synergies and/or trade-offs within and among groups of ES within these zones? Methods: Using structured surveys, we asked 1900 households about their assets, livestock, crops, and collection of forest products. These questions allowed us to assess the number of provisioning ES households used, and whether the ES used are functionally substitutable (i.e., used similarly for nutrition, material, and energy). Finally, we explored synergies and trade-offs among household use of provisioning ES. Results: As agricultural production increased, provisioning ES declined both in total number and in different functional groups used. We found more severe decreases in ES for relatively poorer households. Within the functional groups of ES, synergistic relationships were more often found than trade-offs in all zones, including significant synergies among livestock products (dairy, eggs, meat) and fruits. Conclusions: Considering landscape context provides opportunities to enhance synergies among provisioning services for households, supporting resilient food systems and human well-being.

Agricultural Production Zones Agricultural Intensifcation Synergies and Trade-Offs Landscape Multifunctionality Social-Ecological Systems CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURE INTENSIFICATION ECOSYSTEM SERVICES LANDSCAPE SOCIAL-ECOLOGICAL RESILIENCE ECOSYSTEM SERVICES

Testing innovations for adoption of newer and more adapted maize varieties

Michael Ndegwa Pieter Rutsaert Jason Donovan Jordan Chamberlin (2023, [Objeto de congreso])

Changing Production Conditions Genetic Innovations Maize Hybrids CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA TESTING MAIZE VARIETIES YIELDS FARMERS EXPERIMENTATION

Modelo híbrido de sistemas energéticos para la evaluación del uso de energías renovables

Carlos Iván Torres González (2020, [Tesis de maestría])

En este trabajo proponemos un modelo híbrido para evaluar diferentes escenarios de generación de electricidad con energías renovables que maximiza el bienestar social desde la perspectiva económica contemplando un enfoque técnico sobre la estructura de costos de producción de electricidad. Adicionalmente, realizamos 2 simulaciones del modelo propuesto al sistema eléctrico de Baja California Sur para 10 períodos, contemplando 4 escenarios de producción limpia diferentes. De los resultados observados en ambas simulaciones podemos remarcar 2 puntos en términos de políticas públicas. El primer punto es la importancia de tener múltiples generadores que funcionen con combustibles renovables si se desea producir una proporción significativa de electricidad con FER. El segundo punto es el trade-off entre bienestar y emisiones de CO2. Los resultados sugieren que el aumento del consumo de electricidad es un elemento importante para aumentar el bienestar social. A su vez, el aumento de consumo eléctrico implica un aumento de producción, y por tanto un aumento de emisiones de CO2. Los resultados de la segunda simulación sugieren que con el aumento de la capacidad de generación limpia y costos eficientes, se pueden alcanzar niveles de bienestar casi iguales a los tradicionales, pero con la mitad de emisiones de CO2.

Electric power production -- Effect of renewable energy sources on -- Mexico -- Baja California Sur (State) -- 2015 -- Mathematical models. Carbon dioxide mitigation -- Effect of renewable energy sources on -- Mexico -- Baja California Sur (State) -- 2015 -- Mathematical models. CIENCIAS SOCIALES CIENCIAS SOCIALES

Contrasting spatial patterns in active-fire and fire-suppressed mediterranean climate old-growth mixed conifer forests

Danny L. Fry  (2014, [Artículo])

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference forest sites can help management efforts to restore forests conditions that may be more resilient to future changes in disturbance regimes and climate. In this study, we characterize tree spatial patterns using four-ha stem maps from four old-growth, Jeffrey pine-mixed conifer forests, two with active-fire regimes in northwestern Mexico and two that experienced fire exclusion in the southern Sierra Nevada. Most of the trees were in patches, averaging six to 11 trees per patch at 0.007 to 0.014 ha-1, and occupied 27-46% of the study areas. Average canopy gap sizes (0.04 ha) covering 11-20% of the area were not significantly different among sites. The putative main effects of fire exclusion were higher densities of single trees in smaller size classes, larger proportion of trees (≥56%) in large patches (≥10 trees), and decreases in spatial complexity. While a homogenization of forest structure has been a typical result from fire exclusion, some similarities in patch, single tree, and gap attributes were maintained at these sites. These within-stand descriptions provide spatially relevant benchmarks from which to manage for structural heterogeneity in frequent-fire forest types.

article, climate, controlled study, ecosystem fire history, forest structure, geographic distribution, geographic mapping, land use, mathematical computing, mathematical model, Mexico, spatial analysis, taiga, United States, comparative study, conife CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA