The input reduction principle of agroecology is wrong when it comes to mineral fertilizer use in sub-Saharan Africa

Gatien Falconnier Marc Corbeels Frédéric Baudron Antoine Couëdel leonard rusinamhodzi bernard vanlauwe Ken Giller (2023, [Artículo])

Can farmers in sub-Saharan Africa (SSA) boost crop yields and improve food availability without using more mineral fertilizer? This question has been at the center of lively debates among the civil society, policy-makers, and in academic editorials. Proponents of the “yes” answer have put forward the “input reduction” principle of agroecology, i.e. by relying on agrobiodiversity, recycling and better efficiency, agroecological practices such as the use of legumes and manure can increase crop productivity without the need for more mineral fertilizer. We reviewed decades of scientific literature on nutrient balances in SSA, biological nitrogen fixation of tropical legumes, manure production and use in smallholder farming systems, and the environmental impact of mineral fertilizer. Our analyses show that more mineral fertilizer is needed in SSA for five reasons: (i) the starting point in SSA is that agricultural production is “agroecological” by default, that is, very low mineral fertilizer use, widespread mixed crop-livestock systems and large crop diversity including legumes, but leading to poor soil fertility as a result of widespread soil nutrient mining, (ii) the nitrogen needs of crops cannot be adequately met solely through biological nitrogen fixation by legumes and recycling of animal manure, (iii) other nutrients like phosphorus and potassium need to be replaced continuously, (iv) mineral fertilizers, if used appropriately, cause little harm to the environment, and (v) reducing the use of mineral fertilizers would hamper productivity gains and contribute indirectly to agricultural expansion and to deforestation. Yet, the agroecological principles directly related to soil fertility—recycling, efficiency, diversity—remain key in improving soil health and nutrient-use efficiency, and are critical to sustaining crop productivity in the long run. We argue for a nuanced position that acknowledges the critical need for more mineral fertilizers in SSA, in combination with the use of agroecological practices and adequate policy support.

Manure Crop Yields Smallholder Farming Systems Environmental Hazards CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA BIOLOGICAL NITROGEN FIXATION LEGUMES NUTRIENT BALANCE SOIL FERTILITY AGROECOLOGY YIELD INCREASES LITERATURE REVIEWS

Climate robust soil fertility management by smallholders in Africa, Asia, and Latin America

Tek Sapkota (2023, [Objeto de congreso])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SOIL FERTILITY SMALLHOLDERS FERTILIZERS NUTRIENT MANAGEMENT

Bacterial communities in the rhizosphere at different growth stages of maize cultivated in soil under conventional and conservation agricultural practices

Yendi Navarro-Noya Bram Govaerts Nele Verhulst Luc Dendooven (2022, [Artículo])

Farmers in Mexico till soil intensively, remove crop residues for fodder and grow maize often in monoculture. Conservation agriculture (CA), including minimal tillage, crop residue retention and crop diversification, is proposed as a more sustainable alternative. In this study, we determined the effect of agricultural practices and the developing maize rhizosphere on soil bacterial communities. Bulk and maize (Zea mays L.) rhizosphere soil under conventional practices (CP) and CA were sampled during the vegetative, flowering and grain filling stage, and 16S rRNA metabarcoding was used to assess bacterial diversity and community structure. The functional diversity was inferred from the bacterial taxa using PICRUSt. Conservation agriculture positively affected taxonomic and functional diversity compared to CP. The agricultural practice was the most important factor in defining the structure of bacterial communities, even more so than rhizosphere and plant growth stage. The rhizosphere enriched fast growing copiotrophic bacteria, such as Rhizobiales, Sphingomonadales, Xanthomonadales, and Burkholderiales, while in the bulk soil of CP other copiotrophs were enriched, e.g., Halomonas and Bacillus. The bacterial community in the maize bulk soil resembled each other more than in the rhizosphere of CA and CP. The bacterial community structure, and taxonomic and functional diversity in the maize rhizosphere changed with maize development and the differences between the bulk soil and the rhizosphere were more accentuated when the plant aged. Although agricultural practices did not alter the effect of the rhizosphere on the soil bacterial communities in the flowering and grain filling stage, they did in the vegetative stage.

Community Assembly Functional Diversity Intensive Agricultural Practices Plant Microbiome CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SUSTAINABLE AGRICULTURE TILLAGE SOIL BACTERIA MAIZE

Satellite imagery for high-throughput phenotyping in breeding plots

Francisco Pinto Mainassara Zaman-Allah Matthew Paul Reynolds Urs Schulthess (2023, [Artículo])

Optimized Soil Adjusted Vegetation Index CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA HIGH-THROUGHPUT PHENOTYPING SATELLITES WHEAT MAIZE BREEDING NORMALIZED DIFFERENCE VEGETATION INDEX

Impact of manures and fertilizers on yield and soil properties in a rice-wheat cropping system

Alison Laing Akbar Hossain (2023, [Artículo])

The use of chemical fertilizers under a rice-wheat cropping system (RWCS) has led to the emergence of micronutrient deficiency and decreased crop productivity. Thus, the experiment was conducted with the aim that the use of organic amendments would sustain productivity and improve the soil nutrient status under RWCS. A three-year experiment was conducted with different organic manures i.e. no manure (M0), farmyard manure@15 t ha-1 (M1), poultry manure@6 t ha-1(M2), press mud@15 t ha-1(M3), rice straw compost@6 t ha-1(M4) along with different levels of the recommended dose of fertilizer (RDF) i.e. 0% (F1), 75% (F2 and 100% (F3 in a split-plot design with three replications and plot size of 6 m x 1.2 m. Laboratory-based analysis of different soil as well as plant parameters was done using standard methodologies. The use of manures considerably improved the crop yield, macronutrients viz. nitrogen, phosphorus, potassium and micronutrients such as zinc, iron, manganese and copper, uptake in both the crops because of nutrient release from decomposed organic matter. Additionally, the increase in fertilizer dose increased these parameters. The system productivity was maximum recorded under F3M1 (13,052 kg ha-1) and results were statistically identical with F3M2 and F3M3. The significant upsurge of macro and micro-nutrients in soil and its correlation with yield outcomes was also observed through the combined use of manures as well as fertilizers. This study concluded that the use of 100% RDF integrated with organic manures, particularly farmyard manure would be a beneficial resource for increased crop yield, soil nutrient status and system productivity in RWCS in different regions of India.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA ORGANIC FERTILIZERS YIELDS SOIL PROPERTIES RICE WHEAT CROPPING SYSTEMS

The past, the present, the future, and occupational self-efficacy: an attributions and cultural differences perspective

Daniel Arturo Cernas Ortiz (2023, [Artículo, Artículo])

This study´s objective was to examine empirical relationships between three dimensions of time perspective (future, present fatalistic, and past negative) and occupational self-efficacy. By surveying Mexican (n = 286) and U.S. (n = 272) respondents, we also tested the moderating role of culture. Regression analyses revealed that time perspective dimensions have significant associations with occupational self-efficacy, being future time perspective more potent than its past negative and present fatalistic counterparts. Moderation analyses indicated that none of the examined time perspective-self-efficacy relationships varied significantly between the U.S. and Mexico. Overall, this study suggests that relationships between time perspective and occupational self-efficacy vary according to different temporal dimensions, that future TP is key to develop occupational self-efficacy, and that cultural values may not exert a significant influence on the time perspective-occupational self-efficacy connection.

Perspectiva de tiempo autoeficacia diferencias culturales análisis de moderación CIENCIAS SOCIALES CIENCIAS SOCIALES Time perspective self-efficacy cultural differences moderation analysis

Soil CO2 efflux fluctuates in three different annual seasons in a semideciduous tropical forest in Yucatan, Mexico

El flujo de CO2 del suelo fluctúa en tres temporadas del año en un bosque tropical semideciduo de Yucatán, México

Fernando Arellano-Martín JUAN MANUEL DUPUY RADA ROBERTH ARMANDO US SANTAMARIA José Luis Andrade Torres (2022, [Artículo])

Tropical forest soils store a third of the global terrestrial carbon and control carbon dioxide (CO2) terrestrial effluxes to the atmosphere produced by root and microbial respiration. Soil CO2 efflux varies in time and space and is known to be strongly influenced by soil temperature and water content. However, little is known about the influence of seasonality on soil CO2 efflux, especially in tropical dry forests. This study evaluated soil CO2 efflux, soil temperature, and soil volumetric water content in a semideciduous tropical forest of the Yucatan Peninsula under two sites (flat areas close to and far from hills), and three seasons: dry, wet, and early dry (a transition between the rainy and dry seasons) throughout a year. Additionally, six 24-h periods of soil CO2 efflux were measured within these three seasons. The mean annual soil CO2 efflux was 4±2.2 μmol CO2 m-2 s-1, like the mean soil CO2 efflux during the early dry season. In all seasons, soil CO2 efflux increased linearly with soil moisture, which explained 45% of the spatial-temporal variation of soil CO2 efflux. Soil CO2 efflux was higher close to than far from hills in some months. The daily variation of soil CO2 efflux was less important than its spatial and seasonal variation likely due to small diel variations in temperature. Transition seasons are common in many tropical dry forests, and they should be taken into consideration to have a better understanding of the annual soil CO2 efflux, especially under future climate-change scenarios. © 2022 Mexican Society of Soil Science. All Rights Reserved.

EARLY DRY SEASON SOIL TEMPERATURE SOIL VOLUMETRIC WATER CONTENT TROPICAL DRY FOREST BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Avances en Agricultura Sustentable : Resultados de plataformas de investigación Hub Pacífico Norte 2010-2021

Simon Fonteyne Nele Verhulst (2022, [Libro])

Esta edición presenta los resultados de la red de plataformas en el Hub Pacífico Norte, misma que resulta de la colaboración entre el CIMMYT; el Patronato para la Investigación y Experimentación Agrícola del Estado de Sonora A.C. (PIEAES); el Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias (INIFAP); la Asociación de Agricultores del Río Sinaloa Poniente (AARSP); la Asociación de Agricultores del Río Fuerte Sur (AARFS); la Asociación de Agricultores del Río Culiacán (AARC); la Universidad Autónoma de Sinaloa (UAS); Servicios Agrofinancieros del Norte S.A. de C.V. (SAFINSA); el Club de Labranza de Conservación del Valle del Évora; Granera del Noroeste S.A. de C.V; y el Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California (ICA-UABC). Los lectores podrán encontrar en este libro los resultados de las plataformas con más tiempo de operación, en donde ya se han podido generar suficientes datos para sacar conclusiones basadas en evidencias sólidas. Esperamos que el libro pueda servir de inspiración a los productores para que busquen que sus actividades en el campo sean más productivas, rentables y sustentables.

Plataformas de Investigación Maíz Amarillo Pulgón Áreas de extensión Módulos demostrativos Autosuficiencia Alimentaria Uso de Insumos Ganancias para el Productor Nodos de Innovación CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURA DE CONSERVACIÓN COSTOS DE PRODUCCIÓN EUTROFIZACIÓN MONOCULTIVO DEGRADACIÓN DEL SUELO CONTAMINACIÓN PLAGUICIDAS CAMBIO CLIMÁTICO PLATAFORMAS DE INNOVACIÓN EXTENSIÓN AGRÍCOLA AUTOSUFICIENCIA INSUMOS AGRÍCOLAS CONSERVATION AGRICULTURE PRODUCTION COSTS EUTROPHICATION MONOCULTURE SOIL DEGRADATION CONTAMINATION PESTICIDES CLIMATE CHANGE INNOVATION PLATFORMS AGRICULTURAL EXTENSION SELF-SUFFICIENCY FARM INPUTS

Structural analysis evaluationfor rollers of chassis dynoUsing finite element software

Jesús Emmanuel López Rizo ALFREDO CHAVEZ LUNA JAIME GONZALO SANTANA ESQUIVEL (2023, [Artículo])

This paper discusses the design considerations for a chassis dynamometer, focused on the rollers system used for measuring the power and torque of a vehicle in a university-level workshop. The design must prioritize factors such as safety, ease of use, adaptability to diverse types of vehicles, and the inclusion of safety systems to protect students and the vehicle. The work suggests adaptative features for the design, such as an adjustable fastening system and a compact and portable design, to adapt the structure into a university laboratory. The study also describes common methods for measuring engine power and torque using a chassis dynamometer, and the accurate and reliable measurement systems used for this purpose. This concludes with a discussion of the manufacturing methods used for the chassis dynamometer and a static analysis of the maximum effort capacity in each roller using Von Mises and Goodman fatigue theories. Developing a chassis dynamometer, in accordance the current patents available for workshop practices in a university is essential for providing students with comprehensive training.

Chassis dynamometer Conceptual design Finite element software Power and torque measurement Structural analysis INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Pertinencia del análisis transdisciplinario de la lírica-musical popular latinoamericana

Fermin Monroy Villanueva (2023, [Capítulo de libro])

Capítulo número 3 de la Sección El juego de los signos.

El objetivo de este texto es resaltar la importancia de llevar a la práctica el análisis transdisciplinario de lo que comúnmente es conocido como canción popular, elemento fundamental de los géneros musicales latinoamericanos que aún son considerados representativos de la identidad de sus países. De entre el basto universo integrado por este tipo de producciones, el enfoque está en la música de mariachi mexicano –base de la canción ranchera–, el tango canción argentino y el pasillo ecuatoriano. En este sentido, sostenemos que el análisis de las letras es una vía de aproximación para conocer las condiciones contextuales que caracterizaron la época en que fueron escritas, es decir, al ámbito social, cultural, político, histórico, económico y, de forma muy particular, al emocional. De tal modo, el análisis de la lírica permite reconocer continuidades y resaltar la vigencia de elementos simbólicos que participan en la configuración de sujetos, sociedades y culturas: patrióticos (en la mención de héroes nacionales, lugares y fechas históricas, banderas, escudos, himnos), religiosos (Dios, santos, vírgenes, mártires), espaciales (pueblos, barrios, el campo, las ciudades), conductuales (comportamientos estereotipados en mujeres y hombres, costumbres), etcétera.

Music--Semiotics. Popular music--Latin America--History and criticism. Musical analysis. Intercultural communication. Música popular. Análisis musical. Comunicación intercultural. Semiótica y arte. ML3845 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES MÚSICA, MUSICOLOGÍA