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Soil CO2 efflux fluctuates in three different annual seasons in a semideciduous tropical forest in Yucatan, Mexico

El flujo de CO2 del suelo fluctúa en tres temporadas del año en un bosque tropical semideciduo de Yucatán, México

Fernando Arellano-Martín JUAN MANUEL DUPUY RADA ROBERTH ARMANDO US SANTAMARIA José Luis Andrade Torres (2022, [Artículo])

Tropical forest soils store a third of the global terrestrial carbon and control carbon dioxide (CO2) terrestrial effluxes to the atmosphere produced by root and microbial respiration. Soil CO2 efflux varies in time and space and is known to be strongly influenced by soil temperature and water content. However, little is known about the influence of seasonality on soil CO2 efflux, especially in tropical dry forests. This study evaluated soil CO2 efflux, soil temperature, and soil volumetric water content in a semideciduous tropical forest of the Yucatan Peninsula under two sites (flat areas close to and far from hills), and three seasons: dry, wet, and early dry (a transition between the rainy and dry seasons) throughout a year. Additionally, six 24-h periods of soil CO2 efflux were measured within these three seasons. The mean annual soil CO2 efflux was 4±2.2 μmol CO2 m-2 s-1, like the mean soil CO2 efflux during the early dry season. In all seasons, soil CO2 efflux increased linearly with soil moisture, which explained 45% of the spatial-temporal variation of soil CO2 efflux. Soil CO2 efflux was higher close to than far from hills in some months. The daily variation of soil CO2 efflux was less important than its spatial and seasonal variation likely due to small diel variations in temperature. Transition seasons are common in many tropical dry forests, and they should be taken into consideration to have a better understanding of the annual soil CO2 efflux, especially under future climate-change scenarios. © 2022 Mexican Society of Soil Science. All Rights Reserved.

EARLY DRY SEASON SOIL TEMPERATURE SOIL VOLUMETRIC WATER CONTENT TROPICAL DRY FOREST BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Historical use of water resources. Civil works evolution in Zacatecas state

Carlos Bautista-Capetillo Georgia González-Pérez Hiram Badillo-Almaraz (2021, [Artículo, Artículo])

Availability and demand are essential aspects for the human being when planning is made to provide water to the different sectors that may have need of it; still, the demand of suitable volume of water increases day by day, while the supply decreases gradually. In this inverse relationship, anthropogenic and environmental dynamics are decisive to guarantee the needs of the population, specifically due to the climatic transformations evidenced in recent decades. Throughout history, the state of Zacatecas has suffered the ravages of extreme environmental events, mainly those related to drought. Likewise, but on a lesser extent, severe floods have occurred that have caused socioeconomic damage. In this work, the climatic variations of temperature and precipitation and their influence on the evolution of hydraulic systems for the supply of drinking water in the municipality of Nochistlán de Mejía, Zacatecas are analyzed during the period 1930-2015.

drinking water supply historical development of waterworks climate and its transformations Abasto de agua potable desarrollo histórico de obras hidráulicas clima y sus transformaciones CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Studies of plant hydraulics and water relations in mexican environments: adaptation, physiology, and applications

Estudios sobre hidráulica y relaciones hídricas de plantas en ambientes mexicanos: adaptaciones, fisiología y aplicaciones

RODRIGO MENDEZ ALONZO Mark Olson Horacio Paz Casandra Reyes García CELENE MARISOL ESPADAS MANRIQUE CLARA TINOCO OJANGUREN Santiago Trueba (2022, [Artículo])

Given the outstanding global progress of research on the hydraulic pathway in plants, and its important role as an indicator of plant mortality risk, we reviewed: (1) the adaptive basis of hydraulic traits and their importance for overall plant function; (2) the number of primary scientific articles on plant hydraulics that have been produced in Mexico in the last 40 years, (3) research related to specific environments in Mexico, and (4) the possible applications of plant hydraulics to natural resource management. Our systematic review included 83 articles. The number of publications per year steadily increased over time, reaching its maximum in 2021. Veracruz and Yucatán are the states where the majority of scientific articles on plant hydraulics have been produced, but for most states less than two publications on this subject appeared in ca. 40 years, and none was found for Oaxaca and Chiapas, the most biodiverse states. In plant hydraulics, the most studied biome in Mexico was the tropical dry forest, followed by crops; trees were the most studied growth-form, followed by herbaceous crops and epiphytes. We point to the need of enhancing research in the interface between plant hydraulic function and remote sensing, as well as developing applications in adaptive forest management and ecological restoration. We hope that this review may ignite a national collaborative effort to quantify critical traits that could inform the hydraulic functioning of Mexican ecosystems, particularly in the underrepresented and highly diverse states of Mexico. © 2022 Sociedad Botanica de Mexico, A.C. All rights reserved.

ADAPTATION DROUGHT VULNERABILITY ECOPHYSIOLOGY PLANT WATER RELATIONS SYSTEMATIC REVIEW BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

Soil moisture content and maize grain yield under conventional and conservation agriculture practices - results of short term field tests in liselo, Namibia

Christian Thierfelder (2023, [Artículo])

This article focuses on the results from trials developed to monitor the short-term effects of conventionally tilled systems versus CA on soil quality and crop productivity under conditions of the major cropping systems in central, north-central and north-eastern regions of Namibia. Conventional tillage (CT), Minimum tillage (MT), Minimum tillage, mulch (MT-M), Minimum tillage, rotation (MT-R) and Minimum tillage, mulch and rotation (MT-MR) were the primary treatments tested. Significant differences (p≤0.000) among the treatments were observed in the 0-60 cm soil profiles where MT-M plots had the highest soil moisture content (39.8 mm, Standard Error of Mean 0.2815) over the study period. A significant difference (p=0.0206) in grain yield was observed in the second season with CT plots yielding the highest grain yield (3852.3 kg ha-1, standard error of mean 240.35). Results suggest that CA has the potential to increase water conservation and contribute to reduction of the risk of crop failure. Climate change driven degradation under conventional tillage necessitate alternative sustainable tillage methods. Conservation tillage methods and conservation agricultural practices that minimize soil disturbance while maintaining soil cover need to be adopted more locally as viable alternatives to conventional tillage.

Grain Yield Soil Moisture Content CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE CONVENTIONAL TILLAGE GRAIN YIELDS SOIL WATER CONTENT MAIZE

Estrés académico en estudiantes de enfermería

KARLA VERONICA CASTILLO RÁBAGO (2023, [Tesis de maestría])

El estrés en los estudiantes de educación superior repercute a nivel físico,

emocional y psicológico de cada uno de estos, afectando su salud y rendimiento

académico. Objetivo: Analizar el nivel de estrés académico en los estudiantes de la

facultad de enfermería. Metodología: estudio cuantitativo, transversal,

observacional, analítico. Se utilizó el inventario SISCO, ya que permite identificar el estrés

en estudiantes de educación superior y posgrado. Se aplicó el inventario SISCO a 124

alumnos de primero al séptimo semestre del programa de licenciatura en

enfermería. Resultados: El nivel de estrés en el total de la población fue moderado

en un 58% y profundo en un 40%. El 95.16% manifestó momentos de preocupación

durante el semestre. El sexo femenino muestra mayores niveles de estrés. Los

estresores más frecuentes son los relacionados con las tareas y el tiempo (24%). El

uso de estrategias de afrontamiento es bajo (13.71%). Conclusiones: Los niveles

de estrés son elevados, pero podrían disminuir si los estudiantes utilizaran con

mayor frecuencia estrategias de afrontamiento del estrés de manera consciente.

Stress in higher education students affects the physical, emotional and psychological

level of each one of them, affecting their health and academic performance.

Objective: To analyze the level of academic stress in nursing students.

Methodology: quantitative, cross-sectional, observational, analytical study. The

SISCO inventory was applied to 124 students from the first to the seventh semester

of the nursing degree program. Results: The level of stress in the total population

was moderate in 58% and deep in 40%. 95.16% expressed moments of concern

during the semester. The female sex shows higher levels of stress. The most

frequent stressors are those related to tasks and time (24%). The use of coping

strategies is low (13.71%). Conclusions: Stress levels are high, but could decrease

if students consciously use stress coping strategies more frequently.

MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS nivel de estrés académico; estudiantes universitarios; estresores; síntomas; afrontamiento. academic stress level; University students; stressors; symptoms; coping.

Low thermal conductivity solar domestic water heater

MIGUEL ANGEL PORTA GANDARA JOSE LUIS FERNANDEZ ZAYAS JUAN FRANCISCO VILLA MEDINA NORBERTO CHARGOY DEL VALLE (2022, [Artículo])

"Solar domestic water heaters (SWH) with thermosyphon circulation are the most common commercial applications of solar energy in Mexico. They are also becoming popular in the rest of the world, given their simplicity, good economic returns, and sustainability. Traditionally the solar collector, the piping, and the storage tank are built of copper and steel. However, wáter quality in many parts of the Mexican Northwest has high mineral contents and, when heated, results in early metal pitting corrosion of SWH parts. Short-lived water heaters are bad promoters of the technology. In this work, a SWH thermoplastic Chlorinated Polyvinyl Chloride (CPVC) is built and tested under real operating conditions in La Paz, BCS, Mexico. The optimal design is detected with the aid of a suitable numerical model. Results reveal that a full SWH-CPVC can be technically and economically convenient for the weather conditions of the Northwestern states of Mexico."

Low thermal conductivity solar water heater CPVC solar water heater Solar water heater cooper pitting corrosion Thermosiphon circulation INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA ELECTRÓNICA DISPOSITIVOS TERMOELÉCTRICOS DISPOSITIVOS TERMOELÉCTRICOS

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

Agricultura, agua y cambio climático en zonas áridas de México

SALVADOR EMILIO LLUCH COTA JUAN ALBERTO VELAZQUEZ ZAPATA César Nieto Delgado (2022, [Artículo])

"En este artículo se expone cómo a pesar de que la ciencia y la tecnología han permitido aumentar históricamente la productividad agrícola, hoy día existen grandes retos derivados del cambio climático y la crisis global de abastecimiento de agua. Se comentan algunas medidas de adaptación y manejo del recurso agua, con algunas referencias a nuestra realidad nacional, y se argumenta cómo el enfoque de Nexo, que implica la toma de decisiones sobre el uso del recurso agua de forma transectorial, representa una alternativa de adaptación al cambio climático."

Cambio climático, agricultura, agua, Nexo, adaptación Climate change, agriculture, water, nexus, adaptation CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO CLIMATOLOGÍA CLIMATOLOGÍA REGIONAL CLIMATOLOGÍA REGIONAL