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119 resultados, página 7 de 10

Expanding the WOFOST crop model to explore options for sustainable nitrogen management: A study for winter wheat in the Netherlands

João Vasco Silva Pytrik Reidsma (2024, [Artículo])

Nitrogen (N) management is essential to ensure crop growth and to balance production, economic, and environmental objectives from farm to regional levels. This study aimed to extend the WOFOST crop model with N limited production and use the model to explore options for sustainable N management for winter wheat in the Netherlands. The extensions consisted of the simulation of crop and soil N processes, stress responses to N deficiencies, and the maximum gross CO2 assimilation rate being computed from the leaf N concentration. A new soil N module, abbreviated as SNOMIN (Soil Nitrogen for Organic and Mineral Nitrogen module) was developed. The model was calibrated and evaluated against field data. The model reproduced the measured grain dry matter in all treatments in both the calibration and evaluation data sets with a RMSE of 1.2 Mg ha−1 and the measured aboveground N uptake with a RMSE of 39 kg N ha−1. Subsequently, the model was applied in a scenario analysis exploring different pathways for sustainable N use on farmers' wheat fields in the Netherlands. Farmers' reported yield and N fertilization management practices were obtained for 141 fields in Flevoland between 2015 and 2017, representing the baseline. Actual N input and N output (amount of N in grains at harvest) were estimated for each field from these data. Water and N-limited yields and N outputs were simulated for these fields to estimate the maximum attainable yield and N output under the reported N management. The investigated scenarios included (1) closing efficiency yield gaps, (2) adjusting N input to the minimum level possible without incurring yield losses, and (3) achieving 90% of the simulated water-limited yield. Scenarios 2 and 3 were devised to allow for soil N mining (2a and 3a) and to not allow for soil N mining (2b and 3b). The results of the scenario analysis show that the largest N surplus reductions without soil N mining, relative to the baseline, can be obtained in scenario 1, with an average of 75%. Accepting negative N surpluses (while maintaining yield) would allow maximum N input reductions of 84 kg N ha−1 (39%) on average (scenario 2a). However, the adjustment in N input for these pathways, and the resulting N surplus, varied strongly across fields, with some fields requiring greater N input than used by farmers.

Crop Growth Models WOFOST CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CROPS NITROGEN-USE EFFICIENCY WINTER WHEAT SOIL WATER

Diseño de elementos lúdicos para apoyar el reconocimiento de emociones en el proceso terapéutico cognitivo-conductual de niñas y niños de 6 a 8 años que padecen trastornos de ansiedad en la CDMX y área metropolitana

Alma Karla Buyoli Saavedra (2024, [Tesis de maestría])

179 páginas. Maestría en Diseño y Desarrollo de Productos

En la actualidad, la ansiedad representa uno de los mayores y más silenciosos problemas de la sociedad. Del mismo modo, las infancias y las adolescencias son una población que se ve afectada en gran medida por estos trastornos. En definitiva, estas es una población con una problemática apremiante de considerar, observar y trabajar. Por tal razón, resulta fundamental generar herramientas y estrategias que permitan a niños, niñas y adolescentes identificar y regular sus emociones de manera efectiva. Aprender a identificar las emociones es algo de suma importancia no solo dentro del proceso terapéutico, sino en la vida diaria del infante. En primer lugar, el hecho de reconocer y expresar emociones contribuye a canalizar la ansiedad. De igual forma, esto les ayuda a aprender a enfrentar los problemas de la vida diaria de una manera adecuada; por lo tanto, lo anterior se estima como un beneficio no solo en la infancia, sino también en la edad adulta. Asimismo, un correcto manejo emocional les permite incrementar la percepción de control sobre los sucesos que viven. Igualmente, esto refuerza su habilidad para empatizar, resolver conflictos y llegar a acuerdos, lo que mejora su forma de relacionarse con otras personas. En suma, son diferentes beneficios que se otorgarían al infante al aprender a conocer, identificar y expresar sus emociones. No obstante, estas aportaciones pueden ser mayores si se realizan a través de elementos lúdicos. Para empezar, la recreación es una acción nata y cotidiana en los infantes. El uso de fantasía, el juego simbólico y la imaginación son actividades naturales del desarrollo en el juego de los infantes (Schaefer, 2012). De igual manera, cuando las y los menores juegan, aprenden a tolerar la frustración, a regular sus emociones y a destacar en una tarea que es innata (Schaefer, 2012). En esa medida, el juego es quizá el medio más poderoso y apropiado para el desarrollo en el cual las y los menores pueden construir relaciones con los adultos, desarrollar el pensamiento causal, procesar las experiencias estresantes y aprender habilidades sociales (Chaloner, 2001). Por tal motivo, la propuesta para apoyar el proceso terapéutico se efectúa por medio de elementos lúdicos que permitan a los infantes identificar y expresar emociones a través del juego. Por tal motivo el objetivo de este trabajo es diseñar elementos lúdicos que apoyen a los niños de 6 a 8 años diagnosticados con ansiedad que se encuentren en tratamiento psicológico de la teoría cognitivo-conductual en la CDMX y área metropolitana con el fin de que puedan conocer, identificar y expresar sus emociones.

Games--Design and construction. Child psychotherapy. Play therapy. Games--Therapeutic use. Ansiedad en niños. Terapia de juego. Psicoterapia infantil. GV1230 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS TEORÍA, ANÁLISIS Y CRÍTICA DE LAS BELLAS ARTES

Analysis of adoption of conservation agriculture practices in southern Africa: mixed-methods approach

Adane Tufa Hambulo Ngoma Paswel Marenya Christian Thierfelder (2023, [Artículo])

In southern Africa, conservation agriculture (CA) has been promoted to address low agricultural productivity, food insecurity, and land degradation. However, despite significant experimental evidence on the agronomic and economic benefits of CA and large scale investments by the donor community and national governments, adoption rates among smallholders remain below expectation. The main objective of this research project was thus to investigate why previous efforts and investments to scale CA technologies and practices in southern Africa have not led to widespread adoption. The paper applies a multivariate probit model and other methods to survey data from 4,373 households and 278 focus groups to identify the drivers and barriers of CA adoption in Malawi, Zambia, and Zimbabwe. The results show that declining soil fertility is a major constraint to maize production in Zambia and Malawi, and drought/heat is more pronounced in Zimbabwe. We also find gaps between (a) awareness and adoption, (b) training and adoption, and (c) demonstration and adoption rates of CA practices in all three countries. The gaps are much bigger between awareness and adoption and much smaller between hosting demonstration and adoption, suggesting that much of the awareness of CA practices has not translated to greater adoption. Training and demonstrations are better conduits to enhance adoption than mere awareness creation. Therefore, demonstrating the applications and benefits of CA practices is critical for promoting CA practices in all countries. Besides, greater adoption of CA practices requires enhancing farmers’ access to inputs, addressing drudgery associated with CA implementation, enhancing farmers’ technical know-how, and enacting and enforcing community bylaws regarding livestock grazing and wildfires. The paper concludes by discussing the implications for policy and investments in CA promotion.

Adoption Focus Group Discussion CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE CLIMATE CHANGE

Automated in-season rice crop mapping using Sentinel time-series data and Google Earth Engine: A case study in climate-risk prone Bangladesh

Mustafa Kamal Timothy Joseph Krupnik (2024, [Artículo])

High-resolution mapping of rice fields is crucial for understanding and managing rice cultivation in countries like Bangladesh, particularly in the face of climate change. Rice is a vital crop, cultivated in small scale farms that contributes significantly to the economy and food security in Bangladesh. Accurate mapping can facilitate improved rice production, the development of sustainable agricultural management policies, and formulation of strategies for adapting to climatic risks. To address the need for timely and accurate rice mapping, we developed a framework specifically designed for the diverse environmental conditions in Bangladesh. We utilized Sentinel-1 and Sentinel-2 time-series data to identify transplantation and peak seasons and employed the multi-Otsu automatic thresholding approach to map rice during the peak season (April–May). We also compared the performance of a random forest (RF) classifier with the multi-Otsu approach using two different data combinations: D1, which utilizes data from the transplantation and peak seasons (D1 RF) and D2, which utilizes data from the transplantation to the harvest seasons (D2 RF). Our results demonstrated that the multi-Otsu approach achieved an overall classification accuracy (OCA) ranging from 61.18% to 94.43% across all crop zones. The D2 RF showed the highest mean OCA (92.15%) among the fourteen crop zones, followed by D1 RF (89.47%) and multi-Otsu (85.27%). Although the multi-Otsu approach had relatively lower OCA, it proved effective in accurately mapping rice areas prior to harvest, eliminating the need for training samples that can be challenging to obtain during the growing season. In-season rice area maps generated through this framework are crucial for timely decision-making regarding adaptive management in response to climatic stresses and forecasting area-wide productivity. The scalability of our framework across space and time makes it particularly suitable for addressing field data scarcity challenges in countries like Bangladesh and offers the potential for future operationalization.

Synthetic Aperture Radar Random Forest Boro Rice In-Season Maps CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SAR (RADAR) RICE FLOODING CLIMATE CHANGE