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Modelación de la tendencia de la temperatura en la región sureste de México

VICTORIA ALEJANDRA SEGURA SALDAÑA (2016)

Tesis (Maestría en Ciencias, especialista Estadística).- Colegio de Postgraduados, 2016.

Se usa la metodología de Regresión Polinomial Local para el estudio de la tendencia de la temperatura en la Región Sureste de México. Los datos usados corresponden a temperaturas medias, máximas y mínimas del periodo comprendido entre 1921 y 2012. Los resultados indican que existe una tendencia decreciente de la temperatura media y mínima del periodo de estudio, mientras que la temperatura máxima tiene una tendencia creciente. Así mismo, se analizó el rango de la temperatura y se encontró que éste muestra una tendencia creciente, es decir, el clima de esta región ha llegado a ser más extremoso en los 92 años de estudio. _______________ MODELING TEMPERATURE TRENDS FROM THE SOUTHEAST REGION OF MEXICO. ABSTRACT: In this paper, the method of Local Polynomial Regression is used for the study of temperature trend in the Southeast Region of Mexico. The used data correspond to average, maximum and minimum temperatures between 1921 and 2012. The results show a decreasing trend for the average and minimum temperatures, while the maximum temperature has a growing trend. Furthermore, the temperature range was also analyzed. It was found that this variable has an increasing trend which means that climate of this region has become more extreme in the 92 years of study.

Master thesis

Regresión Polinomial Local Tendencia Temperatura Clima Región Sureste de México Local Polynomial Regression Trends Temperature Weather Southeast Region of Mexico Estadística Maestría CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO METEOROLOGÍA CLIMATOLOGÍA REGIONAL

Dinámica espacio-temporal de oxígeno-temperatura en los lagos Zempoala y Tonatiahua

JUDITH GARCIA RODRIGUEZ Migdalia Díaz Vargas (2012)

Los estudios nictimerales son particularmente importantes en los trópicos para conocer las variaciones ecológicas en ciclos diurnos, y no sólo en estacionales, y lo son no sólo desde el punto de vista conceptual, sino para la aplicación de planes de manejo en diferentes ambientes. El objetivo fue analizar las variaciones del oxígeno disuelto, porcentaje de saturación y temperatura en la columna de agua durante ciclos nictimerales, en los lagos Zempoala y Tonatiahua ubicados en el Parque Nacional Lagunas de Zempoala. Los mayores valores oxígeno disuelto, se presentaron en Zempoala, y la temperatura fue análoga en ambos lagos de acuerdo a los valores promedio totales. La variación de los parámetros estuvo directamente influenciada por la estacionalidad, su morfometría y entorno. El lago Zempoala se consideró como meromictico con tendencias a monomíctico cálido y Tonatiahua como

monomíctico cálido / Héctor Quiroz Castelán, Oliva Mondragón Eslava, Isela Molina Astudillo, Judith García Rodríguez y Migdalia Díaz Vargas.

The nictimeral studies are particularly important in the tropics, to know the ecology variations in diurnal cycles and not only in seasonal cycles. And this is not only from the conceptual point of view, rather for the application of management plans in different environments. The objective was to analyze the variations of dissolved oxygen, percentage of saturation and temperature in the water column during nictimeral cycles, in the lakes of Zempoala and Tonatiahua located in the National Park Lagunas de Zempoala. The greater values of oxygen appeared in Zempoala, and the temperature was analogous in both lakes according to the total values average. Variation of the parameters was directly influenced by the seasonal changes, its morphometry and surroundings. Zempoala lake was considered itself as meromictic with tendencies to warm monomictic and Tonatiahua as warm monomictic.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA INGENIERÍA Y TECNOLOGÍA DEL MEDIO AMBIENTE Temperatura Oxígeno disuelto Estacionalidad Ciclos nictimerales Variaciones ecológicas Variación estacional Lago Zempoala (Morelos) Lago Tonatiahua (Morelos) Temperature Dissolved oxygen Seasonal changes Nictimeral cycles Ecological variations Seasonal variation

Índice de condición en tres clases de talla de la almeja negra Chionista fluctifraga de una pesquería comercial en Sonora, México

Condition index in three size classes of the smooth venus clam Chionista fluctifraga from a commercial fishery in Sonora, Mexico

Jorge Eduardo Chávez Villalba JOSE ALFREDO ARREOLA LIZARRAGA Jesús Ariaana Castillo Durán (2019)

Este estudio muestra el índice de condición (IC) de la almeja Chionista fluctifraga en tres diferentes grupos de talla (pequeñas < 30 mm, medianas 30- 40 mm, y grandes > 40 mm) cosechadas mensualmente durante un año de una pesquería comercial (Sonora, México). La temperatura, salinidad, oxígeno, clorofila a, material orgánico e inorgánico particulado fueron registrados mensualmente en el sitio de estudio. Se detectaron diferencias significativas del IC; mayores para almejas pequeñas (26.5 ± 3.4), seguidas por las medianas (24.0 ± 3.0) y grandes (20.2 ± 3.0). Correlaciones (Pearson) altas y moderadas de temperatura e IC fueron observadas en almejas chicas y medianas. Consecuentemente, la temperatura fue la variable que más afectó el IC y esto fue detectado durante el periodo correspondiente a la reproducción y almacenamiento de nutrientes de esta especie. Con relación a estos procesos, el IC reflejó diferente valor nutritivo para cada grupo de almejas; alto para chicas, moderado para animales medianos y bajo para individuos grandes. Esto puede servir a los productores para seleccionar almejas con alta condición y planear las cosechas.

This study shows the condition index (CI) of the clam Chionista fluctifraga in three different size groups (small <30 mm, medium 30 mm

- 40 mm, and large > 40 mm) harvested monthly during one year in a commercial fishery (Sonora, Mexico). Temperature, salinity, oxygen, chlorophyll a, particulate organic and inorganic concentrations were recorded once-a-month at the study site. Significant differences of CI were detected; higher for small clams (26.5 ± 3.4), followed by medium (24.0 ± 3.0) and large clams (20.2 ± 3.0). High and moderate correlations (Pearson) of temperature and CI were observed in small and medium clams. Thus, temperature was the variable affecting CI the most and this was detected during the period corresponding to reproduction and nutrient storage of the species. In relation to these processes, the CI reflected a different nutritional value for each group of clams; high for small, moderate for medium animals, and low for large individuals. This may serve to producers when selecting clams with high condition and planning harvesting.

Article

Almeja Negra (Chionista Fluctifraga) Smooth Venus Clam (Chione fluctifraga) BIOLOGÍA Y QUÍMICA Estado fisiológico Veneridae Tamaño Temperatura Manejo Physiological state Size Temperature Management

Daylength, temperature and solar radiation effects on the phenology and yield formation of spring durum wheat

Dolors Villegas Karim Ammar Jose Crossa Luis F. García Del Moral Garrido Conxita Royo (2016)

Future food security will depend on crop adaptation to changing environments. We studied the limitations imposed by daylength, temperature and solar radiation on wheat yield in eight field experiments conducted at contrasting northern latitudes and involving 42 adapted spring durum wheat genotypes of divergent phenology, and reduced or without photoperiod sensitivity. Air temperatures averaged from sowing to anthesis (sa) increased from northern to southern sites, while daylength and minimum temperatures from anthesis to maturity (grain filling, gf) followed the opposite trend, due to differences in the latitude of sites. The site effect explained 96 % of the variation in the number of days sa, which was much smaller in southern sites. Average minimum daily temperatures above 6.9 °c before anthesis and below 10.8 °c during gf accompanied by photoperiods during gf of less than 14.2 h resulted in less than 14 000 kernels m−2, which was the threshold below which kernel number limited yield. Radiation during gf lower than 1.8 kj kernel−1 day−1 limited kernel weight, which was then a constraint to the achievement of yield potential.

Article

Daylength Radiation Temperature Yield Components CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Análisis económico del cambio en tres granos básicos de México ante la variabilidad del clima.

ZULIA HELENA CAAMAL PAT (2020)

Tesis (Doctorado en Ciencias, especialista en Economía).- Colegio de Postgraduados, Campus Montecillo, 2020.

En México el consumo de granos en la dieta tradicional se conformó principalmente de maíz y frijol, con la introducción de nuevos cultivos se incorporó el trigo y el arroz. En la dieta de los mexicanos se acompañan los platillos con tortillas, frijoles y arroz, principalmente. En la Ley de Desarrollo Rural Sustentable el maíz, frijol y arroz se consideran productos básicos y estratégicos. Algunos estudios mencionan que un cambio en la temperatura y precipitación podrían afectar de manera negativa el rendimiento, el ingreso agrícola y el consumo. Los objetivos del presente trabajo fueron determinar los efectos del cambio en la temperatura y precipitación pluvial sobre los rendimientos de los tres cultivos por ciclo agrícola (primavera-verano (PV) y otoño-invierno (OI)) en el periodo 1980-2018 y cuantificarlos en el mercado nacional con proyecciones de los escenarios climáticos para México con un horizonte cercano (2015-2039) y bajo distintos escenarios de mitigación. Los resultados obtenidos muestran que para el ciclo PV la temperatura y la precipitación afectaron de manera directa a los tres cultivos. En el ciclo OI la temperatura afectó de manera directa a los tres cultivos, mientras que la precipitación tuvo un efecto indirecto en maíz y frijol, y un efecto directo en arroz. Al utilizar una proyección de un incremento de 1.3 ºC en un escenario de emisiones medias de gases de efecto invernadero (RCP4.5) se encontró que para el ciclo PV la oferta de maíz, frijol y arroz se incrementaría en 8.36, 3.42 y 4.64 % y para el ciclo OI en 8.62, 0.83 y 4.82 %, respectivamente. La demanda de maíz, frijol y arroz aumentaría en 0.43, 5.20 y 0.16 % para PV y en 0.27, 1.27 y 0.05 % para OI, respectivamente. _______________ ECONOMIC ANALYSIS OF THE CHANGE IN THREE GRAINS BASICS OF MEXICO IN THE FACE OF CLIMATE VARIABILITY. ABSTRACT: In Mexico, the consumption of grains in the traditional diet consisted mainly of corn and beans, with the introduction of new crops, wheat and rice were incorporated. In the Mexican diet, the dishes are mainly accompanied with tortillas, beans and rice. In the Sustainable Rural Development Law, corn, beans and rice are considered basic and strategic products. Some studies mention that a change in temperature and precipitation could negatively affect yield, farm income and consumption. The objectives of this dissertation were to determine the effects of the change in temperature and rainfall on the yields of the three crops per agricultural cycle (spring-summer (PV) and autumn-winter (OI)) in the period 1980-2018 and quantify them in the national market with projections of climate scenarios for Mexico with a near horizon (2015-2039) and under different mitigation scenarios. The results obtained show that for the PV cycle, temperature and precipitation directly affected the three crops. In the OI cycle, temperature directly affected the three crops, while precipitation had an indirect effect on corn and beans, and a direct effect on rice. When using a projection of an increase of 1.3 ºC in a scenario of average greenhouse gas emissions (RCP4.5), it was found that for the PV cycle the supply of corn, beans and rice would increase by 8.36, 3.42 and 4.64% and for the OI cycle at 8.62, 0.83 and 4.82%, respectively. The demand for corn, beans and rice would increase by 0.43, 5.20 and 0.16% for PV and by 0.27, 1.27 and 0.05% for OI, respectively.

Doctoral thesis

Modelo de desplazamiento de equilibrio Temperatura Precipitación Rendimiento Maíz Frijol Arroz Equilibrium Displacement Model Temperature Precipitation Yield Maize Beans Rice Economía Doctorado CIENCIAS SOCIALES CIENCIAS ECONÓMICAS ECONOMÍA SECTORIAL AGRICULTURA, SILVICULTURA, PESCA

Physiological breeding I: interdisciplinary approaches to improve crop adaptation

Matthew Paul Reynolds (2012)

Most introductions addressing cereal breeding begin with the Green Revolution. This one is no exception. While this Foreword is certainly not an attempt to write the history of crop physiology and breeding for abiotic stress or give credits, a few landmarks should be noticed on the long road arriving at this important publication. Since the new generation of researchers is not in the habit of reading anything older than three years, I am obliged to provide a brief perspective, having age to my advantage. Looking back at the road will point you to the way ahead. The Green Revolution which consisted of a large increase in cereal grain yield took place in wheat and rice towards the mid-Twentieth Century. It was driven by wheat and rice breeders who sought to reduce plant height in order to reduce lodging and thus also allow for increased nitrogen fertilization. The "Green Revolution" in sorghum (which was not defined as such when it took place) was also driven by a reduction in plant height and took place several decades earlier. It was not directed at increasing yield but rather towards achieving a "combine height" dwarf sorghum that could be harvested mechanically. The bonus of these modifications was an increase in grain yield potential.

Book

Wheat Canopy Temperature Cultivation Phenotypes CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Average conditions of thermal stress in Mexican cities with more than one million inhabitants in the face of climatic change

ADALBERTO TEJEDA MARTINEZ ELDA LUYANDO LOPEZ DOMINGO ERNESTO JAUREGUI OSTOS (2011)

Human bioclimatic scenarios are presented for Mexican cities with more than a million inhabitants. For this, both urban and global warming were considered, the former having been inferred from demographic data, and the latter from the output of general circulation models. Thus, it was possible to estimate increases in temperature and modifications in hygrometric conditions, which were then used to estimate the human bioclimate for the period of 1981-2000 and the decades of 2030 and 2050, as well as the domestic electrical consumption for air-conditioning in housing resulting there from.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA bioclimatic scenarios global warming urban hygrometric conditions temperature

Average conditions of thermal stress in Mexican cities with more than one million inhabitants in the face of climatic change

ADALBERTO TEJEDA MARTINEZ ELDA LUYANDO LOPEZ DOMINGO ERNESTO JAUREGUI OSTOS (2011)

Human bioclimatic scenarios are presented for Mexican cities with more than a million inhabitants. For this, both urban and global warming were considered, the former having been inferred from demographic data, and the latter from the output of general circulation models. Thus, it was possible to estimate increases in temperature and modifications in hygrometric conditions, which were then used to estimate the human bioclimate for the period of 1981-2000 and the decades of 2030 and 2050, as well as the domestic electrical consumption for air-conditioning in housing resulting there from.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA bioclimatic scenarios global warming urban hygrometric conditions temperature