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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

Does access to improved grain storage technology increase farmers' welfare? Experimental evidence from maize farming in Ethiopia

Hugo De Groote Bart Minten (2024, [Artículo])

Seasonal price variability for cereals is two to three times higher in Africa than on the international reference market. Seasonality is even more pronounced when access to appropriate storage and opportunities for price arbitrage are limited. As smallholder farmers typically sell their production after harvest, when prices are low, this leads to lower incomes as well as higher food insecurity during the lean season, when prices are high. One solution to reduce seasonal stress is the use of improved storage technologies. Using data from a randomised controlled trial, in a major maize-growing region of Western Ethiopia, we study the impact of hermetic bags, a technology that protects stored grain against insect pests, so that the grain can be stored longer. Despite considerable price seasonality—maize prices in the lean season are 36% higher than after harvesting—we find no evidence that hermetic bags improve welfare, except that access to these bags allowed for a marginally longer storage period of maize intended for sale by 2 weeks. But this did not translate into measurable welfare gains as we found no changes in any of our welfare outcome indicators. This ‘near-null’ effect is due to the fact that maize storage losses in our study region are relatively lower than previous studies suggested—around 10% of the quantity stored—likely because of the widespread use of an alternative to protect maize during storage, for example a cheap but highly toxic fumigant. These findings are important for policies that seek to promote improved storage technologies in these settings.

Hermetic Storage Randomised Controlled Trial CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA STORAGE PILOT FARMS SEASONALITY WELFARE MAIZE

Transpiration of a tropical dry deciduous forest in Yucatan, Mexico

EVELYN RAQUEL SALAS ACOSTA José Luis Andrade Torres Jorge Perera ROBERTH ARMANDO US SANTAMARIA bernardo figueroa-espinoza Jorge M. Uuh-Sonda EDUARDO CEJUDO ESPINOSA (2022, [Artículo])

The study of forest hydrology and its relationships with climate requires accurate estimates of water inputs, outputs, and changes in reservoirs. Evapotranspiration is frequently the least studied component when addressing the water cycle; thus, it is important to obtain direct measurements of evaporation and transpiration. This study measured transpiration in a tropical dry deciduous forest in Yucatán (Mexico) using the thermal dissipation method (Granier-type sensors) in representative species of this vegetation type. We estimated stand transpiration and its relationship with allometry, diameter-at-breast-height categories, and previously published equations. We found that transpiration changes over time, being higher in the rainy season. Estimated daily transpiration ranged from 0.562 to 0.690 kg m–2 d–1 in the late dry season (April–May) and from 0.686 to 1.29 kg m–2 d–1 in the late rainy season (September–October), accounting for up to 51% of total evapotranspiration in the rainy season. These daily estimates are consistent with previous reports for tropical dry forests and other vegetation types. We found that transpiration was not species-specific; diameter at breast height (DBH) was a reliable way of estimating transpiration because water use was directly related to allometry. Direct measurement of transpiration would increase our ability to accurately estimate water availability and assess the responses of vegetation to climate change. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

SAP FLUX SEASONALITY STAND TRANSPIRATION EVAPOTRANSPIRATION DRY DECIDUOUS FOREST BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Mapas, territorios y narrativas urbanas

María Esther Sánchez Martínez MARCELA DAVALOS LOPEZ Maria del Carmen Bernardez de la Granja JUAN ANTONIO LAVIADA Martín Sánchez Rodriguez Luis Carlos Colon Llamas Anthony Picón Rodríguez Jorge Ernesto Gómez Sánchez Rodrigo O. Tirado (2023, [Libro])

Los mapas nunca se han dibujado solos. Desde Cipango hasta Santafé, pasando por la ciudad de México, la de Michoacán o barrios inadvertidos como Xocotitla, siempre han existido unos ojos para describir o medir los territorios. Entre las varas, millas, cartas de navegación, croquis o fuentes cartográficas no sólo hallamos distancias, sino también abismos culturales. En este libro los planos participan de una historia contextual: revelan tanto el horizonte cultural de quienes los elaboraron como de sus usuarios. Se muestran paisajes narrados, vividos y representados: desde las notas de Marco Polo a las rutas de Cristóbal Colón, hasta los proyectos futuristas irrealizados en Bogotá, pasando por la presencia de las trazas renacentistas en las urbes prehispánicas, la división por cuarteles o por el reparto de tierras comunales indígenas, todo nos invita aquí a compartir una apasionante reflexión sobre cómo se construye el pasado desde el mundo visual de los planos.

Mapas, territorios, urbano, cartografía, planos, croquis. Mexico--Historical geography. Mexico--Maps. City planning--Mexico--History. City planning--Mexico--Mexico City--History. Cartography--Mexico--Mexico City--History. Cartography--Mexico--Michoacán de Ocampo--History. Cartography--Colombia--History. City planning--Colombia--Bogotá. Urbanismo Cartografía Mapas. Cartografía -- Historia. F2175 HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS ARQUITECTURA URBANISMO CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOGRAFÍA CARTOGRAFÍA GEOGRÁFICA

Calibrated multi-model ensemble seasonal prediction of Bangladesh summer monsoon rainfall

Nachiketa Acharya Carlo Montes Timothy Joseph Krupnik (2023, [Artículo])

Bangladesh summer monsoon rainfall (BSMR), typically from June through September (JJAS), represents the main source of water for multiple sectors. However, its high spatial and interannual variability makes the seasonal prediction of BSMR crucial for building resilience to natural disasters and for food security in a climate-risk-prone country. This study describes the development and implementation of an objective system for the seasonal forecasting of BSMR, recently adopted by the Bangladesh Meteorological Department (BMD). The approach is based on the use of a calibrated multi-model ensemble (CMME) of seven state-of-the-art general circulation models (GCMs) from the North American Multi-Model Ensemble project. The lead-1 (initial conditions of May for forecasting JJAS total rainfall) hindcasts (spanning 1982–2010) and forecasts (spanning 2011–2018) of seasonal total rainfall for the JJAS season from these seven GCMs were used. A canonical correlation analysis (CCA) regression is used to calibrate the raw GCMs outputs against observations, which are then combined with equal weight to generate final CMME predictions. Results show, compared to individual calibrated GCMs and uncalibrated MME, that the CCA-based calibration generates significant improvements over individual raw GCM in terms of the magnitude of systematic errors, Spearman's correlation coefficients, and generalised discrimination scores over most of Bangladesh areas, especially in the northern part of the country. Since October 2019, the BMD has been issuing real-time seasonal rainfall forecasts using this new forecast system.

Multi-Model Ensemble Seasonal Forecasting CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CLIMATE SERVICES FORECASTING MONSOONS

San Francisco Xocotitla: representación de un barrio inexplorado

Jorge Ernesto Gómez Sánchez MARCELA DAVALOS LOPEZ (2023, [Capítulo de libro])

Universidad Autónoma Metropolitana (México). Unidad Azcapotzalco. División de Ciencias y Artes para el Diseño. Departamento de Evaluación del Diseño en el Tiempo. Área de Estudios Urbanos.

Este trabajo refiere a la historia de San Francisco Xocotitla, un antiguo pueblo indígena, actualmente ubicado en la alcaldía Azcapotzalco, en la Ciudad de México. Su documentación remite a una de las dos parcialidades en que quedaron asentados los barrios de indios luego de la fundación novohispana de la Ciudad de México. San Francisco Xocotitla – también denominado San Francisco Xocotitlán o simplemente Xocotitla– ocupó un extremo de la parcialidad de Santiago Tlatelolco, al noroeste de la urbe. Su historia y transformaciones espaciales se vinculan al pasado de Azcapotzalco, una jurisdicción ampliamente investigada. Aunque escasos, los escritos y planos sobre esos poblados ignorados por la historia, añaden información sobre cómo se desenvolvieron ante los sucesivos reordenamientos urbanos. Esas imágenes invitan a reconocer distintas maneras de comprender aquel mundo.

Cartography--Mexico--Mexico City--History. Mexico City (Mexico)--Maps. Azcapotzalco (Mexico City, Mexico) City planning--Mexico--Mexico City--History. Urbanismo -- Ciudad de México. Cartografía -- Historia. HUMANIDADES Y CIENCIAS DE LA CONDUCTA CIENCIAS DE LAS ARTES Y LAS LETRAS ARQUITECTURA URBANISMO