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Unanswered questions and unquestioned answers: the challenges of crop residue retention and weed control in Conservation Agriculture systems of southern Africa

Christian Thierfelder Blessing Mhlanga Hambulo Ngoma Paswel Marenya Md Abdul Matin Adane Tufa (2024, [Artículo])

Production and utilization of crop residues as mulch and effective weed management are two central elements in the successful implementation of Conservation Agriculture (CA) systems in southern Africa. Yet, the challenges of crop residue availability for mulch or the difficulties in managing weed proliferation in CA systems are bigger than a micro-level focus on weeds and crop residues themselves. The bottlenecks are symptoms of broader systemic complications that cannot be resolved without appreciating the interactions between the current scientific understanding of CA and its application in smallholder systems, private incentives, social norms, institutions, and government policy. In this paper, we elucidate a series of areas that represent some unquestioned answers about chemical weed control and unanswered questions about how to maintain groundcover demanding more research along the natural and social sciences continuum. In some communities, traditional rules that allow free-range grazing of livestock after harvesting present a barrier in surface crop residue management. On the other hand, many of the communities either burn, remove, or incorporate the residues into the soil thus hindering the near-permanent soil cover required in CA systems. The lack of soil cover also means that weed management through soil mulch is unachievable. Herbicides are often a successful stopgap solution to weed control, but they are costly, and most farmers do not use them as recommended, which reduces efficacy. Besides, the use of herbicides can cause environmental hazards and may affect human health. Here, we suggest further assessment of the manipulation of crop competition, the use of vigorously growing cover crops, exploration of allelopathy, and use of microorganisms in managing weeds and reducing seed production to deplete the soil weed seed bank. We also suggest in situ production of plant biomass, use of unpalatable species for mulch generation and change of grazing by-laws towards a holistic management of pastures to reduce the competition for crop residues. However, these depend on the socio-economic status dynamics at farmer and community level.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA INTEGRATED CROP-LIVESTOCK SYSTEMS CROP RESIDUES ZERO TILLAGE SOCIAL NORMS SUSTAINABLE INTENSIFICATION WEED CONTROL

Movilidad inclusiva, divergencia intrínseca

VICTOR MANUEL COLLANTES VAZQUEZ (2019, [Capítulo de libro])

10 páginas.

Universidad Autónoma Metropolitana. Unidad Azcapotzalco.

En estos tiempos, hablar de diseño, innovación y su influencia en la vida cotidiana es un tema cada día más necesarios. Distintas tendencias se están manifestando en relación a la participación de las tecnologías de la información, accesibilidad movilidad. El tema de este trabajo está relacionado con el desarrollo inclusivo, entendiendo a la discapacidad para caminar como un reto para lo que representa el avanzar hacia una sociedad que considere la totalidad de los habitantes. El caso de estudio es la Alcaldía de Azcapotzalco. Se presenta la experiencia de abordar el tema desde diferentes metodologías que han sido consideradas para enriquecer la investigación y se expresa el aprendizaje a través del reto de estudiar una diversidad de subtemas.

Discapacidad, movilidad, diseño, envejecimiento. Accessible Web sites for people with disabilities. Customer services--Management. Social justice. Accesibilidad de páginas Web a personas con discapacidad. Acceso para personas con discapacidad. HV1568.4 INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LOS ORDENADORES DISEÑO CON AYUDA DE ORDENADOR

Changes in soil organic carbon pools after 15 years of Conservation Agriculture in rice (Oryza sativa)-wheat (Triticum aestivum) cropping system of eastern Indo-Gangetic plains

C.M. Parihar Mahesh Gathala ML JAT (2023, [Artículo])

The present study was carried out at Dr. Rajendra Prasad Central Agricultural University, Samastipur, Bihar during 2021-2023 to focus on examining alterations in SOC pools resulting from conservation agriculture (CA) practices in R-W system in the eastern IGP, following the collection of soil samples from a long-term trial that was initiated in rainy (kharif) season 2006. The trial included eight combinations, namely: conventional tilled rice (Oryza sativa L.) and wheat (Triticum aestivum L.) (CTR-CTW); CT rice and zero till wheat (CTR-ZTW); direct seeded rice (DSR) and wheat on permanent raised beds (PBDSR-PBW); ZTDSR and CT Wheat (ZTDSR-CTW); ZTDSR and ZT wheat without residue (ZTDSR-ZTW-R); ZTDSR-ZT wheat with residue (ZTDSR-ZTW +R); unpuddled transplanted riceZTW (UpTR-ZTW) and ZTDSR-sesbania brown manure-ZTW (ZTDSR-S-ZTW). Results revealed that implementing zero tillage (ZT) combined with residue retention in rice and wheat cultivation led to enhanced levels of soil organic carbon (SOC) across all four fractions, namely very labile (CVL), labile (CL), less labile (CLL), and non-labile (CNL), in comparison to the continuous and rotational tillage practices. The tillage and residue management options significantly affected the lability index (LI) and C pool index (CPI), with zero-tillage and residue retention leading to lower LI and higher CPI values. The management practices significantly affected the C management index (CMI), with zero-tillage and residue retention showing the highest CMI values. Findings showed the potential of CA practices for enhancing soil C quality as well as C sequestration in soil of the Eastern IGP of India.

Carbon Management Index Soil Organic Carbon Fractions CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE SOIL ORGANIC CARBON ZERO TILLAGE

Red neuronal artificial base radial en la estimación de la evapotranspiración de referencia

ROCIO CERVANTES OSORNIO RAMON ARTEAGA RAMIREZ MARIO ALBERTO VAZQUEZ PEÑA WALDO OJEDA BUSTAMANTE (2012, [Artículo])

En la agricultura resulta importante conocer con cierto grado de anticipación algunas variables climáticas tal como la evapotranspiración de referencia, variable primordial en la planeación y distribución del recurso agua en los distritos de riego. En el presente trabajo se utilizaron métodos convencionales y modelos de redes neuronales artificiales, específicamente feedforward backpropagation, con las mismas variables de entradas que sus homólogos modelos empíricos, para estimación de la evapotranspiración de referencia, esto se realizó para la estación Santa Rosa 1 III AC, ubicada en el Distrito 075, Valle del Fuerte, Los Mochis, Sinaloa. Los resultados obtenidos mostraron que las redes neuronales artificiales representan una alternativa de modelo confiable en la estimación de la evapotranspiración de referencia.

Planificación del riego Distritos de riego Evapotranspiración Redes neuronales artificiales INGENIERÍA Y TECNOLOGÍA

El papel del juego en la domesticación de plantas

JAIME MARTINEZ CASTILLO EDUARDO PERALTA IDROVO FRANCISCO PERALTA IDROVO HERNAN PERALTA IDROVO ANDREA LEON CADENA (2022, [Artículo])

Cuando pensamos en la domesticación de plantas, es común que se nos venga a la mente especies que satisfacen las necesidades básicas del humano, como aquellas de uso alimenticio, medicinal y vestido; sin embargo, ¿Existen especies en donde el juego una actividad banal para muchas personasha sido parte de su domesticación? En este artículo revisamos este tema tan interesante usando información sobre las especies domesticadas de frijol (Phaseolus spp.) presentes en Sur América.

FRIJOL LUDICA PALLAR POROTO REGION ANDINA SUR AMERICA TORTA BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Agroecology can promote climate change adaptation outcomes without compromising yield in smallholder systems

Sieglinde Snapp Yodit Kebede Eva Wollenberg (2023, [Artículo])

A critical question is whether agroecology can promote climate change mitigation and adaptation outcomes without compromising food security. We assessed the outcomes of smallholder agricultural systems and practices in low- and middle-income countries (LMICs) against 35 mitigation, adaptation, and yield indicators by reviewing 50 articles with 77 cases of agroecological treatments relative to a baseline of conventional practices. Crop yields were higher for 63% of cases reporting yields. Crop diversity, income diversity, net income, reduced income variability, nutrient regulation, and reduced pest infestation, indicators of adaptative capacity, were associated with 70% or more of cases. Limited information on climate change mitigation, such as greenhouse gas emissions and carbon sequestration impacts, was available. Overall, the evidence indicates that use of organic nutrient sources, diversifying systems with legumes and integrated pest management lead to climate change adaptation in multiple contexts. Landscape mosaics, biological control (e.g., enhancement of beneficial organisms) and field sanitation measures do not yet have sufficient evidence based on this review. Widespread adoption of agroecological practices and system transformations shows promise to contribute to climate change services and food security in LMICs. Gaps in adaptation and mitigation strategies and areas for policy and research interventions are finally discussed.

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CLIMATE CHANGE CROPS FOOD SUPPLY GAS EMISSIONS GREENHOUSE GASES FARMING SYSTEMS AGROECOLOGY FOOD SECURITY LESS FAVOURED AREAS SMALLHOLDERS YIELDS NUTRIENTS BIOLOGICAL PEST CONTROL CARBON SEQUESTRATION LEGUMES

Control biológico de plantas acuáticas exóticas invasoras

MARICELA MARTINEZ JIMENEZ (2014, [Capítulo de libro])

Las plantas acuáticas exóticas invasoras son la principal causa de grandes pérdidas de agua en todos los cuerpos de agua de México y del mundo. Los métodos de control que se han utilizado hasta hoy, además de no haber resuelto el problema, han contribuido al deterioro ambiental. El presente escrito describe el impacto económico y social de estas especies y plantea una metodología que puede asegurar un control eficaz y sustentable.

Especies invasoras Control de malezas Control biológico México BIOLOGÍA Y QUÍMICA