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94 resultados, página 7 de 10

Near-real-time welfare and livelihood impacts of an active war: Evidence from Ethiopia

Kibrom  Abay Guush Berhane Jordan Chamberlin Mehari Hiluf Abay (2023, [Artículo])

Ethiopia recently experienced a large-scale war that lasted for more than two years. Using unique High-Frequency Phone Survey (HFPS) data, which span several months before and after the outbreak of the war, this paper provides evidence on the immediate impacts of the conflict on households’ food security. We also assess potential mechanisms and evaluate impacts on proximate outcomes, including on livelihood activities and access to food markets. We use difference-in-differences and two-way fixed effects estimation to compare trends across affected and unaffected regions (households) and before and after the outbreak of the war. Seven months into the conflict, we find that the war was associated with a 37 percentage points increase in the probability of moderate to severe food insecurity. Using the Armed Conflict Location and Event Data (ACLED), we show that exposure to an additional battle leads to a 1 percentage point increase in the probability of moderate or severe food insecurity. The conflict was associated with significant reduction in access to food through supply chain disruptions and by curtailing non-farm livelihood activities. Non-farm and wage related activities were affected the most, whereas farming activities were relatively more resilient. Our estimates, which likely underestimate the true average effects on the population, constitute novel evidence on the near-real-time impacts of large-scale conflict. Our work highlights the potential of HFPS to monitor active and large-scale conflicts, especially in contexts where conventional data sources are not immediately available.

Phone Surveys CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA WAR CONFLICTS FOOD SECURITY LIVELIHOODS

Impact of different on-farm management practices on bread wheat quality: a case study in the Yaqui Valley

Facundo Tabbita Iván Ortíz-Monasterios Francisco Javier Pinera-Chavez Maria Itria Ibba Carlos Guzman (2023, [Artículo])

BACKGROUND: Continuous development of new wheat varieties is necessary to satisfy the demands of farmers, industry, and consumers. The evaluation of candidate genotypes for commercial release under different on-farm conditions is a strategy that has been strongly recommended to assess the performance and stability of new cultivars in heterogeneous environments and under different farming systems. The main objectives of this study were to evaluate the grain yield and quality performance of ten different genotypes across six contrasting farmers' field conditions with different irrigation and nitrogen fertilization levels, and to develop suggestions to aid breeding programs and farmers to use resources more efficiently. Genotype and genotype by environment (GGE) interaction biplot analyses were used to identify the genotypes with the strongest performance and greatest stability in the Yaqui Valley. RESULTS: Analyses showed that some traits were mainly explained by the genotype effect, others by the field management conditions, and the rest by combined effects. The most representative and diverse field conditions in the Yaqui Valley were also identified, a useful strategy when breeders have limited resources. The independent effects of irrigation and nitrogen levels and their interaction were analyzed for each trait. The results showed that full irrigation was not always necessary to maximize grain yield in the Yaqui Valley. Other suggestions for more efficient use of resources are proposed. CONCLUSIONS: The combination of on-farm trials with GGE interaction analyses is an effective strategy to include in breeding programs to improve processes and resources. Identifying the most outstanding and stable genotypes under real on-farm systems is key to the development of novel cultivars adapted to different management and environmental conditions.

Wheat Quality Bread Wheat Bread-Making CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SOFT WHEAT QUALITY FARMING SYSTEMS

Monitoreo con drones en gráficas con viento dinámico

Jovanni Manuel López Elisea (2024, [Tesis de maestría])

108 páginas. Maestría en Optimización.

Dada una gráfica completa no dirigida, se desea recorrer un subconjunto de sus aristas usando una flotilla de drones. Los drones tienen baterías limitadas que pueden recargarse al regresar a la base y, en principio, el tiempo para recorrer una arista está en función de la distancia entre sus vértices. Sin embargo, ante la presencia de viento el tiempo de recorrer una arista puede depender del sentido en el que se haga. La dificultad del problema aumenta si además la intensidad del viento puede variar de un instante a otro. En esta tesis se aborda el problema anteriormente descrito para el caso particular en el que los vértices son puntos en el plano, el impacto del viento en los tiempos de recorrido de las aristas está relativamente acotado y el subconjunto de las aristas a recorrer inducen un árbol que abarca todos los vértices excepto la base de los drones. Dado que los drones operan simultáneamente y pueden recorrer distintas partes de la gráfica de manera independiente, se desea minimizar el tiempo que emplea el dron con el recorrido más tardado. Esta tesis presenta un modelo matemático para resolver el problema de manera exacta, así como tres heurísticas diferentes para obtener buenas soluciones factibles. La primera de estas heurísticas transforma una solución sin viento y sin batería en una solución con viento y batería. La segunda heurística es un algoritmo glotón sin comunicación entre los drones y la última heurística también es un algoritmo glotón, pero con comunicación entre los drones. Aunque el problema abordado resulta ser lo suficientemente difícil como para que su resolución exacta sea inviable en la práctica, las heurísticas diseñadas son fáciles de implementar y obtuvieron resultados razonables en un tiempo corto de cómputo.

Drone aircraft--Control systems. Drone aircraft--Mathematical models. Mathematical optimization. Heuristic programming. Dynamical systems. Graph theory. Micro vehículos aéreos. Optimización matemática. Programación heurística. Teoría de grafos. TL589.4 CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA MATEMÁTICAS INVESTIGACIÓN OPERATIVA DISTRIBUCIÓN Y TRANSPORTE

Research for development approaches in mixed crop-livestock systems of the Ethiopian highlands

Million Gebreyes James Hammond Lulseged Tamene Getachew Agegnehu Rabe Yahaya Anthony Whitbread (2023, [Artículo])

This study presents processes and success stories that emerged from Africa RISING's Research for Development project in the Ethiopian Highlands. The project has tested a combination of participatory tools at multiple levels, with systems thinking and concern for sustainable and diversified livelihoods. Bottom-up approaches guided the selection of technological interventions that could address the priority farming system challenges of the communities, leading to higher uptake levels and increased impact. Joint learning, appropriate technology selection, and the creation of an enabling environment such as the formation of farmer research groups, the establishment of innovation platforms, and capacity development for institutional and technical innovations were key to this study. The study concludes by identifying key lessons that focus more on matching innovations to community needs and geographies, systems orientation/integration of innovations, stepwise approaches to enhance the adoption of innovations, documenting farmers' capacity to modify innovations, building successful partnerships, and facilitating wider scaling of innovations for future implementation of agricultural research for development projects.

Action Research Systems Thinking CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA INNOVATION PARTNERSHIPS SCALING UP INTEGRATED CROP-LIVESTOCK SYSTEMS

How diverse are farming systems on the Eastern Gangetic Plains of South Asia? A multi-metric and multi-country assessment

Brendan Brown Pragya Timsina Emma Karki (2023, [Artículo])

While crop diversification has many benefits and is a stated government objective across the Eastern Gangetic Plains (EGP) of South Asia, the complexity of assessment has led to a rather limited understanding on the progress towards, and status of, smallholder crop diversification. Most studies focus on specific commodities or report as part of a singular index, use outdated secondary data, or implement highly localized studies, leading to broad generalisations and a lack of regional comparison. We collected representative primary data with more than 5000 households in 55 communities in Eastern Nepal, West Bengal (India) and Northwest Bangladesh to explore seasonally based diversification experiences and applied novel metrics to understand the nuanced status of farm diversification. While 66 crops were commercially grown across the region, only five crops and three crop families were widely grown (Poaceae, Malvaceae, and Brassicaceae). Non-cereal diversification across the region was limited (1.5 crops per household), though regional differentiation were evident particularly relating to livestock and off-farm activities, highlighting the importance of cross border studies. In terms of farmer's largest commercial plots, 20% of systems contained only rice, and 57% contained only rice/wheat/maize, with substantial regional diversity present. This raises concerns regarding the extent of commercially oriented high value and non-cereal diversification, alongside opportunities for diversification in the under-diversified pre-monsoon and monsoon seasons. Future promotional efforts may need to focus particularly on legumes to ensure the future sustainability and viability of farming systems.

Agricultural Production Systems Farming Systems Change CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURAL PRODUCTION CROPPING SYSTEMS DIVERSIFICATION FARMING SYSTEMS SUSTAINABLE INTENSIFICATION