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Smallholder maize yield estimation using satellite data and machine learning in Ethiopia

Zhe Guo Jordan Chamberlin Liangzhi You (2023, [Artículo])

The lack of timely, high-resolution data on agricultural production is a major challenge in developing countries where such information can guide the allocation of scarce resources for food security, agricultural investment, and other objectives. While much research has suggested that remote sensing can potentially help address these gaps, few studies have indicated the immediate potential for large-scale estimations over both time and space. In this study we described a machine learning approach to estimate smallholder maize yield in Ethiopia, using well-measured and broadly distributed ground truth data and freely available spatiotemporal covariates from remote sensing. A neural networks model outperformed other algorithms in our study. Importantly, our work indicates that a model developed and calibrated on a previous year's data could be used to reasonably estimate maize yield in the subsequent year. Our study suggests the feasibility of developing national programs for the routine generation of broad-scale and high-resolution estimates of smallholder maize yield, including seasonal forecasts, on the basis of machine learning algorithms, well-measured ground control data, and currently existing time series satellite data.

Sentinel-2 Smallholder Agriculture Yield Prediction CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA INTENSIFICATION SMALLHOLDERS AGRICULTURE YIELD FORECASTING

Ajustar las condiciones de operación de una prensa hidráulica horizontal de fabricación propia para un proceso de doblado en frío a 90°

Hugo Estrada Pimentel HUGO ARCOS GUTIERREZ JOSE ANTONIO BETANCOURT CANTERA Jan Mayén Chaires John Edison García Herrera (2023, [Artículo])

During the cold-bending process, the tooling suffers considerable damage due to excess pressure. This also causes the machines to break down, causing problems in the precision and quality of the metal parts formed. The precision depends on the operating conditions of the press, the tooling employed, and the elastic recovery effect of the material. This study determines the working conditions for a made-in-house horizontal hydraulic press through an experimental design (DOE). This research carried out the V-forming to 90° (ISO 2768-1) of a hot-rolled carbon steel plate, considering pressure, piston permanence time, and recovery factor (Kr). The experimental and statistical analysis ensures accurate forming while the work pressure decreases by 17% and 33%, respectively, regarding the maximum. This reduction will delay the appearance of fatigue damage and have the operating parameters well established; in turn, it will be possible to design tools according to commercial standards.

Durante el proceso de conformado en frío, las herramientas sufren daños considerables debido al exceso de presión. Esto también causa que las máquinas se rompan, causando problemas en la precisión y calidad de las piezas metálicas formadas. La precisión depende de las condiciones de funcionamiento de la prensa, las herramientas empleadas y el efecto elástico de recuperación del material. Este estudio determina las condiciones de trabajo de una prensa hidráulica horizontal fabricado en casa a través de un diseño experimental (DOE). Esta investigación llevó a cabo el conformado en V a 90° (ISO 2768-1) de una placa de acero al carbono laminada en caliente, teniendo en cuenta la presión, el tiempo de permanencia del pistón y el factor de recuperación (Kr). El análisis experimental y estadístico asegura un conformado preciso, mientras que la presión de trabajo disminuyó en un 17% y 33%, respectivamente, con respecto al máximo. Esta reducción retrasará la aparición de daños por fatiga y tendrá los parámetros de funcionamiento bien establecidos; con estos, a su vez, será posible diseñar herramientas de acuerdo con los estándares comerciales.

Authorship acknowledgement: Hugo Estrada: Conceptualization; methodology; validation; writing; revision; project administration; software; investigation; display; draft writing; reviewing and editing. Hugo Arcos: Conceptualization; methodology; validation; writing; revision; simulation; software; reviewing. José A. Betancourt: Supervision; methodology; validation; writing; revision; draft writing: writing reviewing and editing. Jan Mayen: Supervision; methodology; validation; writing; revision; formal analysis.

John E. García: Conceptualization; supervision; methodology; validation; writing; revision; project management; formal analysis, draft writing: writing reviewing and editing.

Cold forming DOE ANOVA Recovery factor (Kr) Factorial analysis 2k Spring back (SB) Conformado en frío Factor de recuperación (Kr) Análisis factorial 2k Recuperación elástica (SB) INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS OTRAS ESPECIALIDADES TECNOLÓGICAS OTRAS OTRAS

Diversidad arbórea y carbono almacenado en selvas bajo manejo forestal comunitario en Yucatán, México

Tree diversity and carbon stored in communally managed tropical forests in Yucatan, Mexico

MARIA CAMILA HURTADO TORRES JUAN MANUEL DUPUY RADA PATRICIA IRENE MONTAÑEZ ESCALANTE JUAN JOSE MARIA JIMENEZ OSORNIO (2022, [Artículo])

El manejo forestal comunitario sustentable favorece la economía de las comunidades rurales sin comprometer la capacidad de regeneración ni los servicios ecosistémicos que brindan las selvas, como el almacenamiento de carbono. Esta actividad ha sido ampliamente documentada en la Península de Yucatán, pero escasamente evaluada en el estado de Yucatán. En esta investigación se hizo una comparación de composición arbórea, estructura, diversidad y carbono almacenado en la biomasa aérea en tres áreas de selva mediana subcaducifolia con diferente tiempo de regeneración después de un aprovechamiento forestal en el ejido San Agustín (AAF1, AAF10 y AAF+50 años). En cada una se establecieron dos conglomerados conformados por cuatro parcelas circulares de 400 m 2, en las que se identificaron y midieron (diámetro y altura) todos los árboles de diámetro mayor o igual a 7.5 cm. Se analizó la distribución de tamaños de los árboles, la diversidad de especies, su valor de importancia relativo y la biomasa aérea (a partir de ecuaciones alométricas). La especie más dominante fue Bursera simaruba y el AAF+50 presentó la menor dominancia. La distribución de clases diamétricas no varió entre las áreas de aprovechamiento y mostró un patrón de J invertida, lo cual sugiere un alto potencial de regeneración. La diversidad tampoco varió entre las áreas de aprovechamiento, mientras que el carbono almacenado en la biomasa aérea sí, siendo mayor en el AAF+50 (65.2 t /ha). Los resultados indican que el plan de manejo establecido por el ejido no ha afectado la diversidad arbórea ni su potencial de regeneración y permite un alto almacenamiento de carbono.

APROVECHAMIENTO FORESTAL BIOMASA AÉREA DISTRIBUCIÓN DE TAMAÑOS DIVERSIDAD VERDADERA SERVICIOS ECOSISTEMICOS SELVA MEDIANA SUBCADUCIFOLIA BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

A pre-pandemic study about recreational uses in the Mexico Park located at Mexico City (year 2017)

Ramiro Flores-Xolocotzi Sergio Ceballos (2022, [Artículo, Artículo])

A recreational study was carried out through surveys in the Parque México in Mexico City. For this, the relationship between visit patterns with socioeconomic information, uses and perceptions of visitors with 18 years old or older was analyzed. This research uses descriptive statistics and a non-linear canonical correlation analysis to analyze relationships between variables. An ordered probit regression was also performed to determine the variables that explain the frequency of recreational use. It was obtained that the Park mainly receives visitors with at least bachelor's degree (78.6%) and high incomes (more than 50% have a monthly family income higher than $10,000.00 pesos and 27.6% receive more than $30,000.00 per month). Considering the results, the conclusions are that although the highest percentage of the studied population comes from neighborhoods outside the Roma-Condesa Corridor: then the visitors who live in the Corridor and who have higher incomes, have weight in the description of the model. The results allow to conclude too, that higher income increases the frequency of use. It is also observed that the park is used during the Monday to Friday by more than 50% of the population of visitors and with a high percentage of use in the mornings.

urban forestry urban planning leisure green areas correlación canónica no lineal parque urbano probit recreación CIENCIAS SOCIALES CIENCIAS SOCIALES

Sitios Ramsar de la Bahía de La Paz: Amenazas y estrategias para su conservación

Ramsar Sites of La Paz Bay: Threats and strategies for their conservation

Janette Magalli Murillo Jiménez José Juan Pérez Navarro María Concepción Lora Vilchis MARIA DEL ROCIO MARCIN MEDINA LAURA CARREON PALAU Jorge A. Del Angel_Rodríguez Jose Luis Ortiz Galindo Jesús Echevarría Haro (2022, [Artículo])

"En 2017–2018 la Secretaría de Marina del Gobierno de México (SEMAR) realizó actividades de dragado en la Bahía y Ensenada de La Paz, Baja California Sur. Paralelamente ocurrieron afectaciones severas en el sitio Ramsar “Humedales Mogote-Ensenada de La Paz”. Los dragados y el mal manejo de los residuos generaron preocupación ciudadana por el sitio y los organismos que ahí habitan, lo que se manifestó en protestas tanto mediáticas, como legales ante SEMARNAT por algunas organizaciones de la sociedad civil. Esta situación propició la organización de un Foro-Taller realizado el 3 de octubre de 2019, con el fin de evaluar la problemática de los humedales tanto de la Ensenada como de la Bahía de La Paz, ambos incluidos en la Convención Ramsar. El presente trabajo resume los resultados de este evento y refleja la gran preocupación por los sitios Ramsar, tanto de la sociedad civil, como de las diferentes instancias gubernamentales. Estos resultados se integraron en un documento entregado en febrero de 2020 solo a autoridades de SEMARNAT, CONANP y Congreso del Estado de Baja California Sur, previo a la pandemia. Durante el taller se observó una amplia gama de problemas, originados en gran medida por los habitantes y reforzados por el incumplimiento de los compromisos adquiridos por México ante la Convención Ramsar, patente en la desatención de los sitios Ramsar, en particular de los Humedales Mogote-Ensenada de La Paz, donde no hay una normatividad específica que indique la responsabilidad de la gestión de estos ecosistemas. En contraste, el humedal de Balandra cuenta con protección especial al formar parte de una ANP. La conclusión general más importante del evento fue que sólo una sociedad bien organizada, informada de los servicios ambientales que estos sitios proveen, y consciente de su valor como ecosistemas, podrá defender la sustentabilidad de estos sitios."

"In 2017–2018, the Government of Mexico’s Navy Secretariat (SEMAR) carried out dredging activities in Bahía and Ensenada de La Paz, Baja California Sur. In parallel there were severe impacts on the Ramsar site “Humedales Mogote-Ensenada de La Paz”. The dredging and the mis management of the waste generated citizen concern for the site and their inhabiting organisms. Consequently, there were protests that were prosecuted both in the media and legally before SEMARNAT by some non-governmental organizations (ONGs). On October 3, 2019, indignation led to the organization of a Forum-Workshop to assess the problem of wetlands in Bahía and Ensenada de La Paz, included in the Ramsar Convention. Here we present a summary of the Workshop results that reflect the great concern for Ramsar sites, both from civil society, and from different government entities. The results were integrated into a document delivered in February 2020 only to the authorities of SEMARNAT, CONANP and to the Baja California Sur State Congress, because the advent of the Covid-19 pandemic prevented the delivery to all other institutions involved, identified as responsible in the Workshop. Participants observed a wide range of problems in these sites originated largely by residents and reinforced by non-compliance with commitments acquired by Mexico towards the Ramsar Convention, evident in the neglect of the Ramsar sites, in particular the Mogote-Ensenada de La Paz wetlands, where no specific regulation indicates the responsibility of the management of these ecosystems. In contrast, it was observed that the wetland of Balandra has special protection by being part of a Natural Protected Area (ANP, by its acronym in Spanish). The most important general conclusion of this event was that only a we- ll-organized society, informed of the environmental services that these sites provide, and aware of their value as ecosystems, will be able to defend the sustainability of these sites."

Gestión participativa, Dragados, Conservación humedales, Servicios Ecosistémicos, Mortandad delfines CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CONSERVACIÓN CONSERVACIÓN

Waterhole detection using a vegetation index in desert bighorn sheep (Ovis canadensis cremnobates) habitat

Jonathan Gabriel Escobar Flores (2019, [Artículo])

In arid ecosystems, desert bighorn sheep are dependent on natural waterholes, particularly in summer when forage is scarce and environmental temperatures are high. To detect waterholes in Sierra Santa Isabel, which is the largest area of desert bighorn sheep habitat in the state of Baja California, Mexico, we used the normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) from Sentinel-2 satellite images. Waterhole detection was based on the premise that sites with greater water availability, where NDVI was higher, can be identified by their density of vegetation greenness. For the detected waterholes, we estimated the escape terrain (presence of cliffs or steep, rocky slopes) around each by the vector ruggedness measure to determine their potential use by desert bighorn sheep based on the animals’ presence as documented by camera traps. We detected 14 waterholes with the NDVI of which 11 were known by land owners and 3 were unrecorded. Desert bighorn were not detected in waterholes with high values of escape terrain, i.e., flat areas. Waterhole detection by NDVI is a simple method, and with the assistance and knowledge of the inhabitants of the Sierra, it was possible to confirm the presence each waterhole in the field. © 2019 Escobar-Flores et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Article, bighorn sheep, environmental aspects and related phenomena, environmental parameters, habitat, Mexico, nonhuman, normalized difference vegetation index, normalized difference water index, water availability, waterhole, animal, bighorn sheep, CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS CIENCIA FORESTAL CIENCIA FORESTAL

Tallo: A global tree allometry and crown architecture database

Tommaso Jucker Jörg Fischer Jerome Chave David Coomes John Caspersen Arshad Ali Grace Jopaul Loubota Panzou Ted R. Feldpausch Daniel Falster Vladimir Andreevich Usoltsev Stephen Adu-Bredu Luciana Alves Mohammad Aminpour Bhely ANGOBOY Ilondea Niels Anten Cécile Antin yousef askari Rodrigo Muñoz Ayyappan Narayanan Patricia Balvanera Lindsay Banin Nicolas Barbier John J. Battles Hans Beeckman Yannick Enock Bocko Benjamin Bond_Lamberty Frans Bongers Samuel Bowers THOMAS BRADE Michiel van Breugel ARTHUR CHANTRAIN Rajeev Chaudhary JINGYU DAI Michele Dalponte Kangbéni Dimobe jean-christophe domec Jean-Louis Doucet Remko Duursma Moisés Enriquez KARIN Y. VAN EWIJK WILLIAM FARFAN_RIOS Adeline FAYOLLE ERIC FORNI David Forrester Hammad Gilani John Godlee Sylvie Gourlet-Fleury Matthias Haeni Jefferson Hall Jie He Andreas Hemp JOSE LUIS HERNANDEZ STEFANONI Steven Higgins ROBERT J. HOLDAWAY Kiramat Hussain Lindsay Hutley Tomoaki Ichie Yoshiko Iida Hai Jiang Puspa Raj Joshi Seyed Hasan Kaboli Maryam Kazempour Larsary Tanaka Kenzo Brian Kloeppel Takashi Kohyama Suwash Kunwar Shem Kuyah Jakub Kvasnica Siliang Lin Emily Lines Hongyan Liu CRAIG LORIMER Joel Loumeto Yadvinder Malhi Peter Marshall Eskil Mattsson Radim Matula Jorge Arturo Meave del Castillo Sylvanus Mensah XIANGCHENG MI Stephane MOMO Takoudjou Glenn Moncrieff Francisco Mora Sarath Nissanka Kevin O'Hara steven pearce Raphaël Pélissier Pablo Luis Peri Pierre Ploton Lourens Poorter mohsen javanmiri pour Hassan pourbabaei JUAN MANUEL DUPUY RADA Sabina Ribeiro Ryan Casey ANVAR SANAEI Jennifer Sanger Michael Schlund Giacomo Sellan Alexander Shenkin Bonaventure Sonké Frank Sterck Martin Svatek Kentaro Takagi Anna Trugman Farman Ullah Matthew Vadeboncoeur Ahmad Valipour Mark Vanderwel Alejandra Vovides Weiwei WANG Li Qiu Christian Wirth MURRAY WOODS Wenhua Xiang Fabiano de Aquino Ximenes Yaozhan Xu TOSHIHIRO YAMADA Miguel A. Zavala (2022, [Artículo])

Data capturing multiple axes of tree size and shape, such as a tree's stem diameter, height and crown size, underpin a wide range of ecological research—from developing and testing theory on forest structure and dynamics, to estimating forest carbon stocks and their uncertainties, and integrating remote sensing imagery into forest monitoring programmes. However, these data can be surprisingly hard to come by, particularly for certain regions of the world and for specific taxonomic groups, posing a real barrier to progress in these fields. To overcome this challenge, we developed the Tallo database, a collection of 498,838 georeferenced and taxonomically standardized records of individual trees for which stem diameter, height and/or crown radius have been measured. These data were collected at 61,856 globally distributed sites, spanning all major forested and non-forested biomes. The majority of trees in the database are identified to species (88%), and collectively Tallo includes data for 5163 species distributed across 1453 genera and 187 plant families. The database is publicly archived under a CC-BY 4.0 licence and can be access from: https://doi.org/10.5281/zenodo.6637599. To demonstrate its value, here we present three case studies that highlight how the Tallo database can be used to address a range of theoretical and applied questions in ecology—from testing the predictions of metabolic scaling theory, to exploring the limits of tree allometric plasticity along environmental gradients and modelling global variation in maximum attainable tree height. In doing so, we provide a key resource for field ecologists, remote sensing researchers and the modelling community working together to better understand the role that trees play in regulating the terrestrial carbon cycle. © 2022 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

ALLOMETRIC SCALING CROWN RADIUS FOREST BIOMASS STOCKS FOREST ECOLOGY REMOTE SENSING STEM DIAMETER TREE HEIGHT BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL