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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

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

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

Determinantes del comportamiento de queja del consumidor en México

Determinants of consumer complaint behavior in Mexico

IGNACIO JAVIER CRUZ RODRIGUEZ JAVIER GALAN FIGUEROA (2019, [Artículo])

El objetivo del trabajo es explicar los determinantes del comportamiento de queja del consumidor en los niveles socioeconómico y empresa. Para ello se acude a la metodología de datos de panel estático a fin de estimar el impacto de los determinantes de las quejas de los consumidores. Los resultados a nivel socioeconómico indican que las quejas se encuentran determinadas por el ingreso, las conciliaciones a favor de los consumidores y por la población residente en zonas urbanas. Mientras a nivel empresa los resultados muestran que tanto la cuota de mercado como el tamaño de la firma afectan positivamente las quejas. Se concluye que los resultados coinciden con la literatura revisada y que se puede esperar un aumento en el número de quejas presentadas por los consumidores.

This work aims to quantify the determinants of consumer complaint behavior in socioeconomic and business levels. For this purpose, the static panel data methodology is used in order to estimate the impact of consumer complaints both at the federal level of the Mexican Republic and at the level of the main companies that are considered leaders in their field. The results by the state indicate that the complaints are determined by income, reconciliations in favor of consumers and population residing in urban areas.While at the company level, the results show that both market share and company size positively affect consumer complaints. In conclusion, the results agree with the literature reviewed, and a rise in the number of complaints is possible.

HUMANIDADES Y CIENCIAS DE LA CONDUCTA Datos de panel Efectos fijos y efectos aleatorios Satisfacción de los consumidores Quejas del consumidor Panel data models Fixed effects and random effects Consumer complaint

Uso tradicional de plantas: patrimonio de las comunidades indígenas del Parque Nacional Lagunas de Montebello

NAYELY MARTINEZ MELENDEZ Manuel Martínez Meléndez JUANA PATRICIA HERNANDEZ RODRIGUEZ MAURICIO JOSE RIOS (2022, [Artículo])

El Parque Nacional Lagunas de Montebello en Chiapas (México) y su zona de influencia se caracterizan por ser áreas de gran diversidad biológica. Las comunidades indígenas de esta región usan las plantas como un recurso aprovechable que puede satisfacer sus necesidades. Nuestro objetivo fue documentar las especies de uso tradicional y de valor ecológico que las personas reconocen en su localidad. Se realizaron recorridos de campo y talleres comunitarios en los cuales identificamos 88 especies de plantas útiles, la mayoría árboles. Identificar la riqueza de especies del entorno en que viven, es una forma de encaminar acciones de desarrollo enfocadas en la conservación y el manejo de sus recursos forestales como medios de vida.

CHIAPAS ETNOBOTANICA MANEJO DE RECURSOS FORESTALES MUNICIPIO LA TRINITARIA BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA VEGETAL (BOTÁNICA) ECOLOGÍA VEGETAL ECOLOGÍA VEGETAL

First record of Band-tailed Pigeon, Patagioenas fasciata (Columbiformes: Columbidae) in the Sonoran Desert of Baja California

Jonathan Gabriel Escobar Flores MARIANA DELGADO FERNANDEZ OSCAR EDUARDO DELGADO GONZALEZ (2016, [Artículo])

"We report the presence of the Band-tailed Pigeon, which was not previously recorded in the Sonoran Desert in Baja California. The site was 140 km south of the nearest forest. The presence of the pigeon further documents the propensity of Band-tailed Pigeons to wander widely."

Baja California Peninsula; Cataviña; desert; forest; riparian vegetation BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) ECOLOGÍA ANIMAL ECOLOGÍA ANIMAL