RESUMO O pimentão, cultura de importância nutricional, destaca-se por seu valor de vitamina C. Diante da necessidade de práticas agrícolas sustentáveis, o estudo explorou o uso de biocarvões derivados de resíduos regionais como alternativa na cultura de pimentão. Nesse contexto, objetivou-se avaliar o efeito de biocarvões provenientes de cama de frango, fibra de coco e palha de arroz, nas características biométricas e físico-químicas de frutos de pimentão verde, na produção de frutos por planta e na produtividade. A pesquisa foi conduzida em campo no delineamento em blocos casualizados, em esquema fatorial 5 × 3 + 1, referentes a cinco doses de biocarvão (0, 3, 6, 9 e 12 t ha-1) e três tipos de biocarvão (fibra de coco, cama de aviário e palha de arroz) com quatro repetições, mais um tratamento adicional (adubação mineral). Foram avaliadas variáveis biométricas (comprimento e diâmetro dos frutos, espessura da casca, número de frutos, massa do fruto) e físico-químicas dos frutos (sólidos solúveis, acidez titulável, pH, vitamina C e teor de cinzas), produção e produtividade dos frutos. A produção de frutos de pimentão verde não foi influenciada pelos biocarvões, porém as doses de biocarvões influenciaram todas as variáveis analisadas com exceção da espessura da casca. Os teores de vitamina C e de sólidos solúveis foram maiores nos tratamentos com biocarvões e menores com adubação mineral. A maior influência na acidificação dos frutos foi com o biocarvão produzido com palha de arroz. nutricional destacase destaca se sustentáveis contexto objetivouse objetivou frango arroz físicoquímicas físico químicas casualizados 1 0, 0 (0 6 ha1 ha ha-1 repetições mineral . mineral) comprimento casca fruto titulável pH cinzas, cinzas , cinzas) ( ha-

ABSTRACT Bell pepper, a crop of nutritional importance, stands out for its vitamin C content. Given the need for sustainable agricultural practices, the present study explored the use of biochars derived from regional waste as an alternative in bell pepper cultivation. In this context, the present study aimed to evaluate the effect of biochars from poultry litter, coconut fiber, and rice straw on the biometric and physicochemical characteristics of bell pepper fruits, on fruit production per plant and on fruit yield. The experiment was performed in the field in a randomized block design, in a 5 × 3 + 1 factorial scheme, referring to five doses of biochar (0, 3, 6, 9, and 12 t ha-1) and three types of biochar (coconut fiber, poultry litter, and rice straw) with four repetitions, plus an additional treatment (mineral fertilization). Biometric variables (fruit length and diameter, skin thickness, number of fruits, fruit mass) and physicochemical variables of the fruits (soluble solids, titratable acidity, pH, vitamin C, and ash content), production and yield of the fruits were evaluated. The production of bell pepper fruits was not influenced by biochars, but the doses of biochars influenced all variables analyzed with the exception of skin thickness. Vitamin C and soluble solids contents were higher in treatments with biochar and lower with mineral fertilizer. Biochar produced from rice straw had the greatest influence on fruit acidification. importance content practices cultivation context litter fiber design scheme 0, 0 (0 6 9 ha1 ha ha-1 repetitions fertilization. fertilization . fertilization) diameter thickness mass acidity pH content, , content) evaluated fertilizer acidification ( ha-

ABSTRACT Knowledge of the complicated correlation between meteorological variables and crop yield is crucial for food security and agricultural sustainability. This study aimed to investigate how incident solar radiation has affected crop production in the Gadarif region of Sudan over the last 41 years. Using a predictive framework, trends in annual incident solar radiation and temporal variations during sorghum and sesame growing seasons were examined and machine learning (ML) with Extreme Gradient Boosting (XGBoost), Boosted Regression Forest (BRF), and K-Nearest Neighbors (K-NN) was used to predict crop yield. Significant relationships between incident solar radiation indicators and crop yields were identified via detrending approaches and correlation analyses. Results indicate a significant inverse correlation between solar radiation and sorghum yield, and a positive correlation between sesame yield and solar radiation. For both sorghum and sesame yield, K-NN was the most accurate model, demonstrating the significance of incident solar radiation and temperature in predicting crop yield. These findings highlight the potential of ML to improve agricultural forecasting models and inform adaptive agricultural practices in the region. In general, this study provides valuable insights into the dynamic relationship between incident solar radiation and crop yield, emphasizing the importance of considering meteorological factors in agricultural planning and management. sustainability 4 years framework (ML XGBoost, XGBoost , (XGBoost) BRF, BRF (BRF) KNearest K Nearest KNN NN (K-NN analyses model general management (XGBoost (BRF

RESUMO O conhecimento da complicada correlação entre as variáveis meteorológicas e o rendimento das culturas é crucial para a segurança alimentar e a sustentabilidade agrícola. Este estudo está centrado na investigação de como a radiação solar incidente afetou a produção agrícola na região de Gadarif, no Sudão, nos últimos quarenta anos. Usando uma estrutura preditiva, a pesquisa avalia tendências recentes na radiação solar incidente anual, examina variações temporais durante as estações de cultivo de sorgo e gergelim e utiliza técnicas de aprendizado de máquina para prever o rendimento das culturas. Além disso, ML, incluindo Extreme Gradient Boosting (XGBoost), Boosted Regression Forest (BRF) e K-Nearest Neighbours (K-NN), foram empregados para previsão de rendimento. Através de abordagens de redução de tendências e análises de correlação, foram identificadas relações significativas entre os indicadores de radiação solar incidente e o rendimento das culturas. Os resultados indicam uma correlação inversa substancial entre a radiação solar e a produção de sorgo, enquanto a produção de gergelim demonstra uma correlação positiva com a radiação solar. Tanto para o rendimento do sorgo como do gergelim, o K-NN surge como o modelo mais preciso, mostrando a importância da radiação solar incidente e da temperatura na previsão do rendimento das culturas. Estas descobertas destacam o potencial da aprendizagem de máquina para melhorar os modelos de previsão agrícola e informar as práticas agrícolas adaptativas na região. Em geral, este estudo fornece informações valiosas sobre a relação dinâmica entre a radiação solar incidente e o rendimento das culturas, enfatizando a importância de considerar fatores meteorológicos no planeamento e gestão agrícola. Gadarif Sudão anos preditiva anual disso ML XGBoost, XGBoost , (XGBoost) BRF (BRF KNearest K Nearest KNN, KNN NN (K-NN) preciso geral (XGBoost (K-NN

ABSTRACT This study investigates the impact of drying on the shape and size of mung beans (Vigna radiata L.), which are well-regarded for their nutritional, medicinal, and agronomic benefits. Understanding their physical properties at varying moisture levels is crucial for improving agricultural practices from planting through post-harvest. Initially harvested at about 27% moisture content (wet basis, wb), the beans were air-dried naturally to approximately 9% moisture content (wb). The analysis involved measuring the orthogonal axes, length, width, and thickness of 30 representative beans. Parameters such as circularity, sphericity, volume, surface area, projected area, surface-to-volume ratio, and geometric diameter were calculated based on these measurements. Findings indicate that drying reduces the size of mung beans but maintains their circular and spherical shape. The length and width diminish more than the thickness. As drying progresses, the surface-to-volume ratio increases, while the projected area, surface area, and geometric diameter decrease. Vigna L., L L. , L.) wellregarded well regarded nutritional medicinal benefits postharvest. postharvest post harvest. harvest post-harvest 27 wet basis wb, wb wb) airdried air dried 9 wb. . (wb) axes 3 circularity sphericity volume area surfacetovolume measurements progresses increases decrease 2 (wb

RESUMO Objetivou-se com esta pesquisa determinar e avaliar o comportamento da forma e do tamanho do feijão mungo durante a secagem. O feijão mungo tem sido destaque no meio científico e agronômico devido suas propriedades nutricionais, medicinais e produtivas, e o conhecimento de suas propriedades físicas em diferentes teores de água é fundamental para otimização dos processos de plantio, colheita e pós-colheita. Os grãos foram colhidos com o teor de água de aproximadamente 27% (base úmida, bu), e posteriormente submetidos à secagem artificial com ventilação natural, até atingirem o teor de água de aproximadamente 9% (bu). Ao longo do processo de secagem a forma e o tamanho dos grãos foram avaliados mediante determinação dos eixos ortogonais, comprimento, largura e espessura em 30 grãos por repetição. De posse desses dados foram calculados a circularidade, esfericidade, volume, área superficial, área projetada, relação superfície-volume e diâmetro geométrico. A secagem reduz o tamanho dos grãos de feijão mungo, sem alterar de maneira expressiva a sua forma, que pode ser considerada circular e esférica. O comprimento e a largura dos grãos se reduzem em proporção maior que à espessura. A relação superfície/volume aumenta com a secagem, e a área projetada, área superficial e diâmetro geométrico diminuem. Objetivouse Objetivou nutricionais produtivas plantio póscolheita. póscolheita pós colheita. pós-colheita 27 base úmida bu, bu , bu) natural 9 bu. . (bu) ortogonais 3 repetição circularidade esfericidade volume projetada superfícievolume superfície esférica diminuem 2 (bu

Abstract Introduction. Sustainable practices are important tools for mitigating and adapting to climate change, making it essential to understand the factors influencing rice producers’ decisions to adopt conservation practices in their production system. Objective. To determine the causal relationships between variables that explain the adoption of conservation practices by rice producers. Materials and methods. A study was conducted between July and September 2021 in rice production systems in Costa Rica, involving producers from the Brunca, Chorotega, Huetar, and Central Pacific regions through quota sampling. A survey was administered to a total of 67 rice producers. The research was quantitative, identifying degrees of adoption of conservation practices, performing cluster groupings, and using an ordered probit model was to analyze the factors influencing the intensity of adoption of conservation technologies or practices in these production systems. Results. Greater adoption of conservation practices in rice production systems was influenced by the producer’s level of education, membership or affiliation with organizations in rice sector, and land ownership. Conclusions. The design of strategies for conservation practice in rice cultivation benefits from a better understanding of the relationships between socioeconomic, productive, and environmental variables, which can increase the likelihood that a producer will implement and maintain these conservation practices over time.

Resumen Introducción. Las prácticas sostenibles son importantes como herramientas de mitigación y adaptación al cambio climático, por lo que es oportuno comprender qué factores influencian las decisiones de las personas productoras del cultivo de arroz en adoptar una práctica de conservación en su sistema de producción. Objetivo. Determinar las relaciones causales entre las variables que permiten entender la adopción de prácticas de conservación en el cultivo del arroz por parte de las personas productoras. Materiales y métodos. Se realizó un estudio entre julio y septiembre del 2021 en los sistemas productivos de arroz en Costa Rica, con personas productoras de las regiones Brunca, Chorotega, Huetar y Pacífico Central, a través de un muestreo por cuotas. Se aplicó una encuesta a un total de 67 personas productoras de arroz. La investigación realizada fue cuantitativa y se identificaron grados de adopción de prácticas de conservación, se realizaron agrupaciones mediante clústeres y se utilizó un modelo probit ordenado para analizar los factores que influyen en la intensidad de adopción de tecnologías o prácticas de conservación en estos sistemas productivos. Resultados. Una mayor adopción de prácticas de conservación en los sistemas productivos del cultivo de arroz estuvo influenciada por el nivel de escolaridad de la persona productora, la pertenencia o afiliación a organizaciones del sector arrocero y la tenencia de la tierra. Conclusiones. El diseño de estrategias de prácticas de conservación en el cultivo del arroz se beneficia de una mejor comprensión de las relaciones entre las variables socioeconómicas, productivas y del entorno, que permitan aumentar la probabilidad de que una persona productora implemente y mantenga en el tiempo el uso de estas prácticas de conservación.

Abstract Introduction. Seedlings formation under controlled conditions is crucial for cultivating species like strawberry. With LED artificial lighting technology allowing greater control over light, variations in components such as wavelength and intensity can be manipulated to generate seedlings with different characteristics. However, there is a need to generate information for the development of precise and efficient light control practices. Objective. The evaluate strawberry seedling formation under different intensities of violet, blue, and red LED light. Material and methods. The study was conducted in 2020 at the Plant Genetics Laboratory of the Department of Agronomy at the Universidad de Guanajuato, Guanajuato, Mexico. Seeds from San Andreas variety fruits were collected, and seedlings were grown under violet, blue, and red LED light at high, medium, and low intensities. Color determinations of cotyledon area, Chroma saturation index, and Hue angle were performed. Additionally, physio-technical, chemical, and antioxidant activity variables were measured. Results. The most suitable treatments were high and medium intensity violet light, as well as high intensity blue light, with germination range exceeding 60 %. Seedlings did not elongate or thin out and exhibited the largest cotyledons areas and chlorophyll concentrations. Furthermore, these light treatments consumed, on average, 31.2 % less electrical energy. Conclusions. In addition to white light, the most suitable treatments for strawberry seedlings formation were high and medium intensity violet light, as well as high intensity blue light. It is suggested to evaluate violet and blue light treatments in other cultivars to confirm their positive effect on strawberry seedlings. Red light limited germination and showing higher antioxidant activity.

Resumen Introducción. La formación de plántulas en condiciones controladas es fundamental para cultivar especies como la fresa. Dado que la tecnología de iluminación artificial LED ha permitido un mayor control de la luz, la variación de componentes como la longitud de onda y la intensidad pueden ser manipulados para generar plántulas con diferentes características. Sin embargo, es necesario generar información para el desarrollo de prácticas precisas y eficientes en el control de la luz. Objetivo. Evaluar la formación de plántulas de fresa en diferentes intensidades de luz LED violeta, azul y roja. Materiales y métodos. El estudio se realizó durante 2020 en el Laboratorio de Genética Vegetal del Departamento de Agronomía de la Universidad de Guanajuato, Guanajuato, México. Se recuperaron semillas de frutos de la variedad San Andreas y se sembraron plántulas en luz LED violeta, azul y roja a intensidades alta, media y baja. Se realizaron determinaciones de color del área del cotiledón, índice de saturación de color y ángulo Hue. Además, se midieron variables fisiotécnicas, químicas y actividad antioxidante. Resultados. Los tratamientos más adecuados fueron luz violeta de intensidades altas y medias; así como luz azul de alta intensidad, debido a que el porcentaje de germinación superó el 60 %. Las plántulas no se alargaron ni adelgazaron, presentaron las mayores áreas de cotiledones y concentraciones de clorofila. Además, estos tratamientos de luz consumieron en promedio 31,2 % menos energía eléctrica. Conclusiones. Además de la luz blanca, los tratamientos más adecuados para la formación de plántulas de fresa fueron la luz violeta a alta y media intensidad, así como la luz azul a alta intensidad. Se sugiere evaluar los tratamientos de luz violeta y azul en otros cultivares para confirmar el efecto positivo en las plántulas de fresa. La luz roja limitó la germinación y mostró mayor actividad antioxidante.

Resumen Antecedentes: Los sistemas agrícolas tradicionales en Mesoamérica son adaptaciones ancestrales a los diversos y complejos ambientes. La tezcalera representa uno de ellos. Preguntas: ¿En qué contexto ambiental se desarrolla la tezcalera? ¿Cuáles son las prácticas de manejo que se llevan a cabo en la tezcalera?¿Cómo afectan a la riqueza, composición y abundancia de las arvenses? ¿Cómo influyen en la resiliencia del sistema agrícola, de los bosques tropicales secos y al mantenimiento de los recursos para la subsitencia? Especies de estudio: Arvenses en tezcaleras con diferente manejo. Sitio y años de estudio: Zumpahuacán, Estado de México, 2020-2021 Métodos: Entrevistas sobre prácticas de manejo de la tezcalera. Registro de la riqueza, composición y abundancia de malezas en parcelas con diferente historia de manejo. Resultados: Las tezcaleras se originan de la roza-tumba-quema y siguen diferentes rutas: el tlacolol-milsol-regeneración o potrero, y recientemente, cultivo de Agave. Registramos 161 morfoespecies y 45 familias botánicas; 95 % nativas de la selva baja caducifolia. Veinticinco son endémicas de la región del Balsas y 34 están en alguna categoría de riesgo. La riqueza y abundancia de las arvenses varió entre tezcaleras. La composición florística fue similar; 65 % tuvieron valor tangible o intangible. Conclusiones: La tezcalera es una unidad biocultural y un agroecosistema resiliente. Las prácticas tradicionales favorecen la riqueza y composición de las especies nativas. Los herbicidas y la introducción del cultivo de Agave desplazan a los cultivos tradicionales, poniendo en riesgo la agrobiodiversidad local.

Abstract Background: Traditional agricultural systems in Mesoamerica are adaptations of ancient farmers to the complex and varied environments. Tezcalera represents one of them. Questions: How is the environmental context under which the tezcalera develop? Which management practices are followed in tezcalera? How do these management practices affect weeds' richness, composition, and abundance? How do these management practices contribute to the resilience of the agricultural system, the tropical dry forests, and to the maintenance of subsistence resources? Studied species: Weeds growing in tezcaleras with different management. Study site and dates: Zumpahuacán, Estado de México, 2020-2021. Methods: Twenty-four collaborators were interviewed about the environmental, technological, and cultural aspects of tezcalera. We recorded weeds' richness, composition, and abundance in seven plots with different management histories. Results: Tezcaleras originate from the slash-burn process and follow different paths: tlacolol-milsol-shallow plot, potrero, and recently, Agave crop. We recorded 161 morphospecies from 45 botanical families; 95 % were native to tropical dry forests. Twenty-five species are endemic to the Balsas region, and thirty-four are at risk. Richness and abundance varied between tezcaleras, where tlacolol plots exhibited the highest values. Plant composition was similar; 65 % had intangible or tangible values. Conclusions: Tezcalera is a biocultural unit and a resilient agroecosystem. Traditional practices remain and positively impact the richness and composition of native weeds. The uncontrolled use of herbicides and the introduction of Agave crop are displacing traditional crops and modifying traditional practices, risking local agrobiodiversity.

Abstract Cattle production acquired special relevance in the northeast of Río Negro province over sheep farming. The change in the sanitary status to the south of the Colorado River in 2013, favored the progressive development of the activity. In addition, the activities from irrigated areas were diversified including forage and grain production. The purpose of this work is to understand the practices and strategies developed by cattle producers, based on the following research questions, What level of homogeneity and heterogeneity do the livestock producers of the region present? How did the changes occurred in the region affected management and production management practices? The quantitative-qualitative approach oriented to the actors, allowed identifying tree livestock social types, as well as the relationship with the production systems, revealing itself as an effective methodology for understanding their specificities. The testimonies collected in this investigation give an indication of the changes that occurred in a sector that was favored by the economic conditions provided by the barrier that boosted the value of the farm, generating a greater number of opportunities.

Resumen La producción bovina adquirió especial relevancia en el nordeste de la provincia de Río Negro por sobre la ganadería ovina. El cambio en el estatus sanitario al sur del río Colorado en 2013, favoreció el progresivo desarrollo de la actividad. Además, las áreas de bajo riego se diversificaron con la producción forrajera y de granos. El presente trabajo tiene por finalidad entender las prácticas y estrategias desarrolladas por los productores ganaderos bovinos a partir de las siguientes preguntas de investigación: ¿qué nivel de homogeneidad y heterogeneidad presentan? y ¿cómo incidió, en sus prácticas de manejo y gestión de la producción, los cambios acontecidos en la región? El abordaje cuanti cualitativo orientado a los actores, permitió identificar tres tipos sociales ganaderos, así como la relación con la producción y la diversificación de actividades prediales y extraprediales, revelándose como una metodología eficaz para la comprensión de sus especificidades. Los testimonios recabados en esta investigación dan indicio de los cambios sucedidos en un sector que fue favorecido por las condiciones económicas brindadas por la barrera que impulsó el valor de la hacienda, generando un mayor número de oportunidades.

Resumo A produção bovina adquiriu especial relevância no nordeste da província de Río Negro por sobre o gado ovino. O câmbio no status sanitário ao sul do rio Colorado em 2013, favoreceu o progressivo desenvolvimento da atividade. Além disso, as áreas de baixo risco diversificaram-se com a produção de forragem e de grãos. Este trabalho tem como finalidade entender as práticas e estratégias desenvolvidas pelos produtores pecuários bovinos a partir das seguintes perguntas de investigação: qual nível de homogeneidade e heterogeneidade apresentam? e como incidiu, em suas práticas de manuseio e gestão da produção, as modificações acontecidas na região? A abordagem quanti qualitativo orientado aos atores, permitiu identificar três tipos sociais pecuários, assim como a relação com a produção e a diversificação de atividades prediais e extraprediais, revelando-se como uma metodologia eficaz para a comprenssão de suas especificidades. Os testimunhos conseguidos nesta investigação dão indícios dos câmbios acontecidos num setor que foi favorecido pelas condições econômicas brindadas pela barreira que impulsou o valor da fazenda gerando um maior número de oportunidades.

Abstract Over the last decades, institutional interventions in the Andean regions of northwest Argentina have been mainly focused on stimulating the production of Andean crops through Agroecological Transition Processes. Despite these efforts, Andean crop production remains marginal compared to conventional commercial horticulture. In this paper I intend to provide ethnographic data to challenge the premature diagnosis according to which both production models compete with each other to the disadvantage of more sustainable practices, in order to argue that, at times, both forms of production may constitute strategies deployed by the same extended families in order to achieve two complementary goals, namely: to generate sufficient economic income for domestic reproduction, but at the same time to maintain the production of crops of affective and cultural value, as well as the plots where they are produced, which are of greater ancestral importance but less profitable, and which through this type of creative solutions are protected from the excessive aggressiveness of conventional agriculture. decades Processes efforts horticulture practices that times goals namely reproduction value produced profitable agriculture

Resumen La intervenciones institucionales que tuvieron lugar en las regiones andinas del noroeste argentino durante las últimas décadas han estado ancladas principalmente en estimular la producción de cultivos andinos mediante Procesos de Transición Agroecológica. A pesar de estos esfuerzos, la producción de cultivos andinos sigue resultando marginal en comparación a la horticultura comercial mediante agricultura convencional. En este artículo propongo aportar datos etnográficos que permitan poner en debate el diagnóstico apresurado según el cual ambos modelos productivos compiten entre sí en perjuicio de las prácticas más sustentables, para sostener que, en ocasiones, ambas formas de producción pueden constituir estrategias desplegadas por las mismas familias extensas con el fin de lograr dos objetivos complementarios, a saber: generar ingresos económicos suficientes para la reproducción doméstica, pero a la vez mantener vigente la producción de cultivos de valor afectivo y cultural, así como las parcelas agrícolas donde éstos son producidos, de mayor importancia ancestral pero menor rentabilidad, y que mediante este tipo de soluciones creativas son amparados de la excesiva agresividad de la agricultura convencional. Agroecológica esfuerzos convencional sustentables ocasiones complementarios saber doméstica cultural producidos rentabilidad

Abstract Bahía Blanca and Punta Alta are the most important urban agglomeration in the south of the Province of Buenos Aires, Argentina, with 300 extensive farmers in their area of influence. In this semi-arid region, wind erosion affects human health in the city, due to suspended dust, and the sustainability of agricultural production, due to soil loss. Faced with this critical territorial problem, the Rural Extension Agency of the National Institute of Agricultural Technology Bahía Blanca has conducted out surveys and interacted with different actors to set up a Territorial Observatory of Local Sustainable Practices. This article aims to describe the levels of information generated in this process, which is still under development, and to assess its usefulness in recognizing transformations towards the use of sustainable practices in the territory. The study adopts an exploratory-descriptive design. Geographic Information Systems maps and the MESMIS method generated information layers. These were socialized and disseminated to contribute to understanding the territorial dynamics in the adoption of sustainable innovations and to reduce the margin of error in the decisions of public-private actors in the territory for its development and sustainability.

Resumen Las ciudades de Bahía Blanca y Punta Alta son el aglomerado urbano más importante del sur de la Provincia de Buenos Aires, en la República Argentina, con 300 productores extensivos en su área de influencia. En esta región semiárida, la erosión eólica afecta a la salud humana en la ciudad, por el polvo en suspensión, y a la sustentabilidad de la producción agropecuaria, por la pérdida de suelo. Frente a esta problemática crítica del territorio, la Agencia de Extensión Rural del Instituto Nacional de Tecnología Agropecuaria Bahía Blanca ha efectuado relevamientos e interactuado con distintos actores para constituir un Observatorio Territorial de Prácticas Sostenibles Locales. El objetivo del artículo es describir los niveles de información generados en este proceso, que aún está en desarrollo, y valorar su utilidad para reconocer transformaciones hacia el empleo de prácticas sustentables en el territorio. El estudio adopta un diseño exploratorio-descriptivo. Se utilizaron mapas de Sistemas de Información Geográfica y el método MESMIS para generar capas de información, las cuales se socializaron y difundieron para contribuir al conocimiento de la dinámica territorial para la adopción de innovaciones sustentables y reducir el margen de error en decisiones de actores público-privados del territorio para su desarrollo y sustentabilidad.

Resumo As cidades de Bahía Blanca e Punta Alta são o aglomerado urbano mais importante do sul da Provincia de Buenos Aires, na República Argentina, com 300 produtores extensivos na sua área de influência. Nesta região semiárida, a erosão eólica afeta à saúde humana na cidade, por el polvo en suspensión, y a la sustentabilidad de la producción agropecuaria, pela pérdida do solo. Frente a essa problemática crítica do território, a Agência de Extensião Rural do Instituto Nacional de Tecnologia Agropecuária Bahía Blanca tem efetuado relevamentos e interatuado com distintos atores para constituir um Observatório Territorial de Práticas Susutentáveis Locais. O objetivo do artigo é descreveros níveis de informação gerados neste processo, que ainda está em desenvolvimento, e valorar sua utilidade para reconhecer transformações em vias do emprego de práticas sustentáveis no território. O estudo adota um desenho exploratório-descritivo. Utilizam-se mapas de Sistemas de Informação Geográfica e o método MESMIS para gerar capas de informação, as quais foram socializadas e difundiron para contribuir ao conhecimento da dinâmica territorial para a adoção de inovações sustentáveis e reduzir o margem de erro em decisões de atores público-privados do território para seu desenvolvimento sustentável.

There is growing recognition that climate change is a worldwide phenomenon with far-reaching effects and that it is linked to an increase in the frequency of extreme weather occurrences. In rural areas of most of the sub-Saharan countries and other developing countries in the world, the frequent occurrences of extreme weather events such as flooding, heat waves, and drought have significantly destroyed livelihood activities of poor communities. Unfavorable geographic characteristics, a lack of resources, and a higher reliance on climate-sensitive sources of income among many community members in poor nations all contribute to the impact. These include livelihood activities associated with land use and agricultural practices. Sadly, the population's capacity and incentive to stay in rural areas have been altered because of climate change and its detrimental impacts on agricultural output, income, and subsistence living; as a result, many rural dwellers are migrating to urban areas. Rural populations migrate to urban areas in search of economic opportunities to earn a living. It is evident that the expected opportunities in urban areas are not always available; thus, most of the rural migrants are stuck in informal settlements, shanty towns, and slums without access to services. Consequently, it is evident that climate change is somehow transferring poverty from rural to urban areas. This study adopted the push/pull theory as a theoretical framework to guide the discussion and analysis. Based on an extensive review of the existing literature using qualitative document analysis, the purpose of this article is to examine the role of climate change on rural-urban migration, which ultimately contributes to the increase in urban poverty. The article concludes by reviewing the current (limited) research on climate change and poverty and argues for a research agenda in the context of sub-Saharan Africa toward sustainable ways to respond to the challenges of climate-induced migration, urbanization, and poverty.

ABSTRACT While zinc (Zn) is an essential element for plant metabolism, anthropic activities and poor agricultural practices as well as frequent use of pesticides and fertilizers rich in this element can cause toxic levels of Zn to plants. A study was done under greenhouse conditions in Tunja, Colombia in which bulb onion seedlings (Allium cepa L.) were exposed to 0 (control), 20, 40, and 80 mg L-1 of Zn in mixture with a nutrient solution containing macro and micronutrients. The excess Zn in the solution had a rather drastic effect on the accumulation of dry weight and reduced the absolute growth rate, the specific leaf area, the water uptake, the water use efficiency, the leaf area, the length of all roots per plant, and on the contrary, increased the content of total soluble solids in the juice of the bulb. Thus, most growth-related variables were negatively affected from 20 mg L-1 and up of Zn in solution. In addition, the toxic effect of Zn is more drastic on plants growing in nutrient solution compared to those growing in soil. The experiment lasted until 54 days after transplanting, which was the limit for plant survival, especially at higher concentrations of Zn, so it can be inferred that these plants have low tolerance to high Zn contents in the substrate.

RESUMEN A pesar de que el zinc (Zn) es un elemento esencial para el metabolismo de las plantas, las actividades antrópicas y las malas prácticas agrícolas, así como también, el uso frecuente de plaguicidas y fertilizantes ricos en este elemento pueden causar que niveles tóxicos de Zn estén disponibles para las plantas. Se realizó en Tunja, Colombia, un trabajo en invernadero en el que plántulas de cebolla de bulbo (Allium cepa L.) se expusieron a 0 (control), 20, 40, y 80 mg L-1 de Zn en solución nutritiva. El exceso de Zn en la solución tuvo un efecto bastante drástico sobre la acumulación de peso seco, también redujo los valores de la tasa absoluta de crecimiento, del área foliar especifica, del consumo de agua, de la eficiencia en el uso del agua, del área foliar, de la longitud de raíces y, por el contrario, incrementó el contenido de solidos solubles totales en el zumo del bulbo. De este modo, la mayoría de las variables relacionadas con el crecimiento fueron afectadas negativamente a partir de 20 mg L-1 de Zn en la solución. Además, el efecto tóxico del Zn es más drástico cuando las plantas crecen en solución nutritiva en comparación a cuando crecen en suelo. Por otro lado, el experimento duró solo hasta 54 días después del trasplante, dado que fue el momento máximo que pudieron soportar las plantas, especialmente aquellas que se expusieron a contenidos de Zn más elevados, con lo que se puede inferir que estas plantas tienen baja tolerancia a contenidos elevados de Zn en el sustrato.

Verlorenvlei is a globally important RAMSAR wetland on the arid west coast of South Africa. A prolonged drought between 2016 and 2021 and increasing competition for water from the agricultural sector resulted in extremely low water levels. We used historical aerial and satellite imagery from 1942 and rainfall and water level data for the past 50 years, to assess habitat changes within the estuarine functional zone of the Verlorenvlei Estuarine Lake. Prior to the drought, lake water levels and water surface area remained stable (1113 ± 27 ha (SE)). Since then, there has been a 64% decrease in open water area, exposing 193 ha of sandbanks, of which 190.9 ha were hyper-sulfidic pyrite-rich. The water in the lower lake was hypersaline (>100), and in the middle, it was acidic (pH<3). The low water level plus sediment and nutrient input from surrounding agriculture resulted in a localised increase in reeds. Additional pressures, such as fires, have reduced the above-ground biomass of reeds and sedges, potentially altering surface morphology and reducing stored carbon. Despite flooding and filling up in June 2023, the lake remained in an acidic state (3.9-4.3). Similar low-lake level, hypersaline and acidic conditions are predicted to become more common under future climate change scenarios where aridity and extreme weather events are anticipated. Inflow of fresh water into the estuary and control of farming practices are required to keep the Verlorenvlei in a functional state, with long-term monitoring necessary to assess the ecological condition in response to restoration actions. SIGNIFICANCE: We assessed the habitat changes in Verlorenvlei, an estuarine lake on the arid west coast of South Africa. Estuarine lakes are scarce, and an extended drought greatly reduced the water surface area, exposing hyper-sulfidic pyrite-rich soils, leading to lake acidification and a negative response from biota. Competition for water from agribusiness and the burning of reeds are added pressures. Subsequent heavy rains have been slow to buffer lake acidity, and the impacts thereof serve as a warning for the management of similar ecosystems and their ecological water requirements, especially under climate change where extreme weather conditions, increased aridity and competition for water are realities.

RESUMEN Trichoderma, un género de hongos filamentosos es ampliamente utilizado en la agricultura debido a sus propiedades y usos diversos, destacando su habilidad para funcionar como un agente biocontrolador contra diversos fitopatógenos. El éxito de Trichoderma se basa en múltiples mecanismos de acción, que incluyen antibiosis, micoparasitismo, competencia por espacio y nutrientes, producción de enzimas y metabolitos secundarios con actividad antimicrobiana y la estimulación de la respuesta de defensa de las plantas ante los patógenos. Esta mini revisión se centra en los mecanismos de acción de Trichoderma como biocontrolador y sus potencialidades para el uso en la agricultura. Este género de hongos filamentosos con capacidad para inhibir el crecimiento de patógenos, estimular el crecimiento de las plantas y mejorar la calidad del suelo lo convierten en un recurso valioso para los agricultores. El conocimiento de estos mecanismos puede ayudar a mejorar aún más su uso en la agricultura y promover prácticas agrícolas sostenibles.

ABSTRACT Trichoderma, a genus of filamentous fungi, is widely used in agriculture due to its various properties and uses, particularly its ability to function as a biocontrol agent against various phytopathogens. The success of Trichoderma is based on multiple mechanisms of action, including antibiosis, mycoparasitism, competition for space and nutrients, production of enzymes and secondary metabolites with antimicrobial activity, and stimulation of the plant defense response against pathogens. This mini review focuses on the mechanisms of action of Trichoderma as a biocontrol agent and its potential for use in agriculture. Its ability to inhibit the growth of pathogens, stimulate plant growth, and improve soil quality makes it a valuable resource for farmers. Understanding these mechanisms can further improve its use in agriculture and promote sustainable agricultural practices.

Abstract During the neoliberal regime, food policy in Mexico focused on the paradigm of ensuring physical and economic access to safe and cheap food; However, the measures to meet this objective caused, among other things, a trade deficit in basic foods such as corn, orientation of production towards export crops, environmental and people’s health deterioration. In response to this problem, in the mid-1990s, the concept of food sovereignty gained strength. This paradigm contributed to making visible the problems faced by small family productive units and the importance of including in public policy actions that respect the diversity of cultivated seeds, traditional agricultural practices, the care of resources and the reproduction of culturally accepted foods. In this context, the objective of this work is to characterize corn production in three lake regions of Michoacán (Mexico) from the perspective of food sovereignty and, based on this, raise considerations for its strengthening. A comparative analysis was carried out on the approaches of the food sovereignty paradigm based on own information obtained through a survey applied to corn producers from three lake regions of the state of Michoacán. The results show the coexistence of diverse production systems ranging from traditional to intensive production in each region, with manifest experiences of food sovereignty in the Pátzcuaro region and silent in the Cuitzeo region.

Resumen Durante el régimen neoliberal, la política alimentaria en México se centró en el paradigma de asegurar el acceso físico y económico a alimentos inocuos y baratos; sin embargo, las medidas para atender este objetivo provocaron, entre otras consecuencias, un creciente déficit en la balanza comercial de alimentos básicos como el maíz, la orientación de la producción hacia cultivos de exportación, y el paulatino deterioro de la calidad ambiental y de la salud de las personas. Frente a esta compleja problemática, a mediados de la década de los años noventa, surge con fuerza el paradigma de soberanía alimentaria, cuyo concepto contribuyó a visibilizar los problemas que enfrentan las pequeñas unidades productivas familiares y la importancia de incluir en la política pública acciones que respeten la diversidad de las semillas cultivadas, las prácticas agrícolas tradicionales, el cuidado de los recursos y la reproducción de alimentos culturalmente aceptados. En este contexto, el presente trabajo tiene como objetivo caracterizar la producción de maíz de tres regiones lacustres de Michoacán desde la perspectiva de la soberanía alimentaria y, a partir de ello, delinear algunas consideraciones de política pública para su fortalecimiento. Para ello, se realizó un análisis comparado sobre los planteamientos del paradigma de soberanía alimentaria a partir de información propia obtenida mediante una encuesta aplicada a productores de maíz de tres regiones lacustres del estado de Michoacán. Los resultados muestran la coexistencia de diversos sistemas productivos que van desde los tradicionales hasta la producción intensiva en cada región, observando experiencias de soberanía alimentaria manifiestas en la región Pátzcuaro y silenciosas en la región Cuitzeo.

Abstract Background: Agroforestry systems integrate agricultural, forestry and cultural diversity and have been little studied in coastal regions of Mexico. The SA managed by mixtecs and afro-mexicans are unknown. Questions: Which agroforestry systems are found in Mixtec and Afro-Mexican communities? Which are the forms of management, agricultural and agroforestry practices and useful species in agroforestry systems? Studied species: Various. Study site and dates: Santa María Chicometepec, Cerro de la Esperanza, Collantes, Santa Elena Comaltepec, San Agustín Chayuco, Santiago Tetepec, Oaxaca. October 2021 to October 2022. Methods: Sixty semi-structured interviews were conducted with local specialists in three Mixtec and three Afro-Mexican communities. Questions were asked about traditional agroforestry systems, agricultural, agroforestry and management practices, and useful species. Tours and collections of herbarium specimens were carried out. Each system was described, management and agroforestry practices were categorized; and the number of useful species by category of use and cultural group was recorded. Results: Six agroforestry systems were recorded and described: milpa, pastures, plots, acahuales; piñal and coconut. Agricultural practices in Mixtec communities are carried out with basic tools and inputs and the production is for self-consumption and local sale, while in Afro-Mexican communities they are technical, and their destination is regional sale. The most common agroforestry practices were the boundaries and isolated trees. Conclusions: The cultural groups share agroforestry systems, forms of management, and number of useful species is similar, but they differ in agricultural practices. In the agroforestry systems, edible and timber species (firewood, poles, fences, construction) are mainly conserved.

Resumen Antecedentes: Los sistemas agrosilvícolas (SA) integran diversidad agrícola, forestal y cultural. En regiones costeras de México han sido poco estudiados, particularmente los manejados por mixtecos y afromexicanos de la costa de Oaxaca. Preguntas: ¿Qué SA se encuentran en comunidades mixtecas y afromexicanas?, ¿Cuáles son las especies útiles, formas de manejo, prácticas agrícolas y agroforestales de los SA? Especies de estudio: Diversas. Sitio y años de estudio: Santa María Chicometepec, Cerro de la Esperanza, Collantes, Santa Elena Comaltepec, San Agustín Chayuco, Santiago Tetepec, Oaxaca. Octubre 2021 a octubre 2022. Métodos: Se realizaron 60 entrevistas semiestructuradas a especialistas locales en tres comunidades mixtecas y tres afromexicanas. Se preguntó acerca de especies útiles, sistemas agrosilvícolas, prácticas agrícolas, agroforestales y de manejo. Se realizaron recorridos y colectas de ejemplares de herbario. Se describió cada sistema por sus prácticas agroforestales y de manejo. Se registró el número de especies útiles por categoría de uso y grupo cultural. Resultados: Se documentaron y describieron seis SA: milpa, potreros, solares, acahuales, piñal y cocotal. Las prácticas agrícolas en comunidades mixtecas se realizan con herramientas e insumos básicos y la producción tiene un fin de autoconsumo y venta local, mientras que en comunidades afromexicanas son tecnificadas y su destino es la venta regional. Linderos y árboles aislados fueron las prácticas agroforestales más comunes. Conclusiones: Mixtecos y Afromexicanos comparten SA, formas de manejo y prácticas agroforestales, difieren en las prácticas agrícolas. En los SA se conservan principalmente especies comestibles y maderables. El número de especies útiles es similar en comunidades mixtecas y afromexicanas.