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Strategies steering intensification pathways of farmers in central Malawi

Carl Timler Jeroen Groot Sieglinde Snapp Pablo Tittonell (2023, [Artículo])

Smallholder farmers face many challenges to improve their livelihoods and food security. Intensification of agricultural production can help to achieve these goals. Yet farmers are highly heterogenous in their strategies towards intensification, potentially following unsustainable intensification pathways. Using Q Methodology, we ascertain different strategies regarding farm improvement and intensification of smallholder farmers in the Dedza and Ntcheu Extension Planning Areas in Central Malawi. These strategies were associated to coherent sequential choices as expressed in “managerial intensification pathways” (MIPs). Three main strategies emerged: Seed Saving Peasants, Aspirant Modern Farmers and Entrepreneurial Business(wo)men. These were subsequently linked to four MIPs. Seed Saving Peasants focus strongly on local seed systems and post-harvest protection of grains, but also allocate more labour to improving crop residue use and manure quality, thus pointing to a labour-oriented MIP. Aspirant Modern Farmers willingly adopt hybrid seeds and inorganic fertilizers but require more extension support; these farmers follow a technology-oriented MIP. Entrepreneurial Business(wo)men are early adopters of new technologies and benefit from improved access to market information and suppliers of new technologies and follow a sustainable technology-based or techno-ecological intensification pathway. This study shows that strongly contrasting perspectives on intensification exist among smallholders and it is expected that their preferred intensification choices will have diverging impacts on the sustainability of their farms. A diversity of extension, advice and incentive instruments will be needed to support farmer decision making towards sustainably intensified farms.

Smallholder Farmers Q Methodology CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SMALLHOLDERS STRATEGIES SUSTAINABLE INTENSIFICATION

Hymenopteran parasitoid complex and fall armyworm: a case study in eastern India

Tapamay Dhar PRATEEK MADHAB BHATTACHARYA Mahesh Gathala Alison Laing (2024, [Artículo])

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) has significantly affected maize crop yields, production efficiency, and farmers’ incomes in the Indian Eastern Gangetic Plains region since it was first observed in India in 2018. A lack of awareness by maize growers of the appropriate selection, method, and timing of insecticide application not only creates a barrier to sustainable FAW control but also contributes to increased environmental pollution, reduced human health and increased production costs. We demonstrated that FAW inflicted the most damage in early whorl growth stage of maize, regardless of whether chemical insecticides were applied. FAW egg masses and larvae collected from maize fields in which no insecticides had been sprayed showed high parasitism rates by parasitoid wasps; in contrast fields that had been sprayed had much lower rates of parasitism on FAW. Ten hymenopteran parasitoids were observed in maize fields across the study region, suggesting a diversity of natural methods to suppress FAW in maize at different growth stages. These included two FAW egg parasitoids and eight FAW larval parasitoids. Microplitis manilae Ashmead was the most abundant FAW larval parasitoid species, and Telenomus cf. remus was the dominant FAW egg parasitoid species. Endemic FAW parasitoids such as those observed in this study have great potential as part of a sustainable, cost-effective agroecological management strategy, which can be integrated with other methods to achieve effective control of FAW.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA FALL ARMYWORMS MAIZE INSECTICIDES INSECT CONTROL

Multicriteria assessment of alternative cropping systems at farm level. A case with maize on family farms of South East Asia

Santiago Lopez-Ridaura (2023, [Artículo])

CONTEXT: Integration of farms into markets with adoption of maize as a cash crop can significantly increase income of farms of the developing world. However, in some cases, the income generated may still be very low and maize production may also have strong negative environmental and social impacts. OBJECTIVE: Maize production in northern Laos is taken as a case to study how far can farms' performance be improved with improved crop management of maize with the following changes at field level: good timing and optimal soil preparation and sowing, allowing optimal crop establishment and low weed infestation. METHODS: We compared different farm types' performance on locally relevant criteria and indicators embodying the three pillars of sustainability (environmental, economic and social). An integrated assessment approach was combined with direct measurement of indicators in farmers' fields to assess eleven criteria of local farm sustainability. A bio-economic farm model was used for scenario assessment in which changes in crop management and the economic environment of farms were compared to present situation. The farm model was based on mathematical programming maximizing income under constraints related to i) household composition, initial cash and rice stocks and land type, and ii) seasonal balances of cash, labour and food. The crop management scenarios were built based on a diagnosis of the causes of variations in the agronomic and environmental performances of cropping systems, carried out in farmers' fields. RESULTS AND CONCLUSIONS: Our study showed that moderate changes in crop management on maize would improve substantially farm performance on 4 to 6 criteria out of the 11 assessed, depending on farm types. The improved crop management of maize had a high economic attractiveness for every farm type simulated (low, medium and high resource endowed farms) even at simulated production costs more than doubling current costs of farmers' practices. However, while an improvement of the systems performance was attained in terms of agricultural productivity, income generation, work and ease of work, herbicide leaching, improved soil quality and nitrogen balance, trade-offs were identified with other indicators such as erosion control and cash outflow needed at the beginning of the cropping season. SIGNIFICANCE: Using farm modelling for multicriteria assessment of current and improved maize cropping systems for contrasted farm types helped capture main opportunities and constraints on local farm sustainability, and assess the trade-offs that new options at field level may generate at farm level.

Bio-Economic Farm Model Smallholder Farms CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CASH CROPS INDICATORS SMALLHOLDERS CROPPING SYSTEMS MAIZE

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

Estudio de la factibilidad ambiental, desarrollo sustentable, urbano, social y legal para el desarrollo de estrategias participativas y de mediación social para la construcción de sistemas de humedales artificiales (SHA) para el saneamiento del aporte del Río Amanalco a la Presa Valle de Bravo

Ricardo Víctor López Mera Jóse luis Martínez Ruiz Eduardo López Ramírez Gemma Cristina Millán Malo Denise Soares (2018, [Documento de trabajo])

Este proyecto ha tenido como objetivo general identificar, mediante un estudio social y legal, la factibilidad de adquirir los predios donde se implementarán los sistemas de humedales artificiales, así como determinar los posibles impactos sociales asociados a su construcción, operación y mantenimiento, con el fin de proponer estrategias de mitigación y lograr la aceptación por parte de las comunidades seleccionadas en el estudio.

Humedales Factores socioeconómicos Calidad de vida Estudios de factibilidad CIENCIAS SOCIALES

Propiedades fisicoquímicas del aceite de semillas de Jatropha curcas de poblaciones silvestres en México

NIDIA ARAIZA LIZARDE MIGUEL ANGEL ANGULO ESCALANTE TEODORO REYNOSO GRANADOS MARIA MAGDALENA ORTEGA NIEBLAS Lilia Alcaráz Meléndez Pedro Cruz Hernández (2015, [Artículo])

"Existe la necesidad de estudiar fuentes renovables de energía a partir de plantas oleaginosas con este potencial. La semilla de Jatropha curca se caracteriza por su alto contenido de aceite. En México solo existen estudios enfocados en evaluar las propie-dades fisicoquímicas del aceite de J. curcas silvestre y cultivada en la región sur. El objetivo de este trabajo, fue evaluar las propiedades fisicoquímicas del aceite de J. curcas silvestre en tres ecotipos del estado de Sinaloa (noroeste de México) y su aplicación en la elaboración de biodiesel. Los resultados obtenidos fueron que el contenido de aceite del germen fue de 52 a 56%. La viscosidad, densidad específica, índice de acidez, peróxido, yodo y refracción no mostraron diferencias significativas en las semillas colectadas en los tres ecotipos en estudio. Los ácidos grasos saturados más abundantes fueron el palmítico (4 a 6%) y esteárico (3 a 4%). Los ácidos grasos insaturados más abundantes fueron el oleico (44 a 46%) y linoleico (42 a 44%). Las características fisicoquímicas del aceite de J. curcas de Sinaloa son similares a las del sur de México y otros países, esto sugiere que el germoplasma del noroeste del país podría ser considerado para su conservación, aprovechamiento racional y producción de biodiesel."

"The need for studying sources of renewable energy is important starting from potential oleaginous plants. Jatropha curcas seed is characterized by its high oil content. In Mexico studies are focused on evaluating the physicochemical properties of J. curcas oil in wild plants cultivated in the southern region. The objective of this study was to evaluate these properties in three ecotypes of wild J. curcas of Sinaloa and their oil application in biodiesel production. The oil content of the germ was found to be 52 to 56%. Viscosity, density, acidity index, peroxide, iodine, and refraction showed no signif-icant differences in the seeds collected from the three ecotypes in our study. The most abundant saturated fatty acids were palmitic (4 to 6%) and stearic (3 to 4%). The most abundant unsaturated fatty acids were oleic (44 to 46%) and linoleic (42 to 44%). Physi-cochemical characteristics of J. curcas oil of Sinaloa specimens are similar to those of southern Mexico and other countries, which suggest that the germplasm of the north-western part of the country could be considered for conservation, rational utilization, and biodiesel production."

Fatty acid, ecotype, fatty acid, physicochemical analysis Ácidos grasos, biodiesel, ecotipos, análisis fisicoquímicos, Jatropha BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOQUÍMICA LÍPIDOS LÍPIDOS

Desarrollo de tecnologías para tratamiento de aguas residuales. Etapa 2: remoción de compuestos emergentes mediante procesos avanzados

Petia Mijaylova Nacheva (2020, [Documento de trabajo])

El objetivo del proyecto es evaluar la remoción de compuestos emergentes mediante la aplicación de procesos avanzados en el tratamiento de aguas residuales. Con el fin de alcanzar dicho objetivo se ha desarrollado e implementado una técnica analítica, la cual permite la determinación de microcontaminantes emergentes ácidos y neutros sin derivatización de las muestras. De igual forma, se ha elucidado la degradación de compuestos farmacéuticos en agua mediante oxidación fotocatalítica usando películas con estructura nanotubular de TiO2.

Tratamiento de aguas residuales Contaminantes emergentes Remoción de contaminantes Productos farmacéuticos y de cuidado personal INGENIERÍA Y TECNOLOGÍA

Viabilidad y barreras para el ejercicio del derecho humano al agua y saneamiento en México

RICARDO VICTOR LOPEZ MERA JOSE LUIS MARTINEZ RUIZ (2014, [Libro])

El libro tiene dos objetivos principales: por un lado, la necesidad de reflexionar respecto a los retos, alcances y limitaciones sociales, económicas, políticas, ambientales y legales para el ejercicio del derecho humano al agua y, por el otro, el saneamiento en los diferentes escenarios del país.

Derecho humano al agua Saneamiento Estudios de factibilidad México CIENCIAS SOCIALES