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

Dead level contour technical design parameters required for sustainable crop production in semi-arid areas of Zimbabwe

Menas Wuta Isaiah Nyagumbo (2021, [Artículo])

Maize Yield Optimum Interval Dead Level Contours CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA TECHNOLOGY DRY SPELLS MAIZE YIELDS RAINWATER HARVESTING

Contrasting spatial patterns in active-fire and fire-suppressed mediterranean climate old-growth mixed conifer forests

Danny L. Fry  (2014, [Artículo])

In Mediterranean environments in western North America, historic fire regimes in frequent-fire conifer forests are highly variable both temporally and spatially. This complexity influenced forest structure and spatial patterns, but some of this diversity has been lost due to anthropogenic disruption of ecosystem processes, including fire. Information from reference forest sites can help management efforts to restore forests conditions that may be more resilient to future changes in disturbance regimes and climate. In this study, we characterize tree spatial patterns using four-ha stem maps from four old-growth, Jeffrey pine-mixed conifer forests, two with active-fire regimes in northwestern Mexico and two that experienced fire exclusion in the southern Sierra Nevada. Most of the trees were in patches, averaging six to 11 trees per patch at 0.007 to 0.014 ha-1, and occupied 27-46% of the study areas. Average canopy gap sizes (0.04 ha) covering 11-20% of the area were not significantly different among sites. The putative main effects of fire exclusion were higher densities of single trees in smaller size classes, larger proportion of trees (≥56%) in large patches (≥10 trees), and decreases in spatial complexity. While a homogenization of forest structure has been a typical result from fire exclusion, some similarities in patch, single tree, and gap attributes were maintained at these sites. These within-stand descriptions provide spatially relevant benchmarks from which to manage for structural heterogeneity in frequent-fire forest types.

article, climate, controlled study, ecosystem fire history, forest structure, geographic distribution, geographic mapping, land use, mathematical computing, mathematical model, Mexico, spatial analysis, taiga, United States, comparative study, conife CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

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

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

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

Trade-off in the design of sustainable cropping systems at a regional level: A case study on the North China plain

Jeroen Groot XiaoLin Yang (2022, [Artículo])

Holistic Analysis Model-Based Analysis CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CROP ROTATION FOOD SECURITY WATER USE ENVIRONMENTAL PROTECTION ECONOMIC VIABILITY

Solar Irrigation Pump (SIP) sizing tool: user manual (Beta version)

Santosh Mali Paresh Shirsath (2022, [Libro])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SOLAR POWERED IRRIGATION SYSTEMS PUMPS IRRIGATION WATER MANUALS

Conservation agriculture based sustainable intensification: India updates

ML JAT (2021, [Objeto de congreso])

CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CONSERVATION AGRICULTURE SUSTAINABLE INTENSIFICATION LAND MANAGEMENT TILLAGE PLANT ESTABLISHMENT BIOMASS WATER MANAGEMENT

La mirada de niños con NEE y maestros sobre la participación paterna en su aprendizaje: efectos de una intervención educativa

YANKO NORBERTO MEZQUITA HOYOS MARIA JOSE DE LILLE QUINTAL YOANY MARILY SOLIS KU (2016, [Artículo])

Esta investigación de corte cualitativo, tuvo como objetivo describir las percepciones que niños con NEE y sus maestros tienen sobre las estrategias de apoyo a su aprendizaje que tienen los padres antes y después de una intervención educativa. Para esto fue necesario, conocer desde la mirada de niños y profesores, las conductas de apoyo que brindan los padres en las actividades escolares a sus hijos y las situaciones que han facilitado o dificultado su involucramiento. Se trabajó con 6 docentes, que tienen en su grupo a uno o más alumnos con NEE y 8 alumnos con NEE de una escuela primaria pública, localizada al poniente de la ciudad de Mérida, Yucatán. En el diagnóstico se encontró que según los maestros, los padres de familia tienen un concepto impreciso de Necesidades Educativas Especiales, lo que repercute en sus expectativas académicas de sus hijos. Profesores y niños mencionaron que entre las principales barreras para el apoyo a sus hijos, se encuentran: su bajo nivel educativo y su comprensión de las tareas, la falta de paciencia, la carencia de información de cómo apoyarlos y la carencia de tiempo debido al trabajo. Se diseñó e implementó un taller para promover su participación, en el cual se consideraba tanto información teórica como experiencias personales de los participantes. Posterior a la implementación del taller los profesores consideraron que mejoró el conocimiento de los padres sobre NEE y coincidieron con los niños en que se mejoró la participación de los padres en el aprendizaje de sus hijos, implementando nuevas estrategias y mostrándose más colaborativos y tolerantes. Sin embargo los profesores destacaron la falta de participación de los padres en actividades escolares y comunitarias.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA Necesidades educativas especiales Profesores Niños