Víctor L Barradas | Universidad Nacional Autónoma de México (original) (raw)

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Papers by Víctor L Barradas

Botanical sciences, Dec 15, 1999

Agrociencia, Aug 15, 2018

Ecosistemas y Recursos Agropecuarios, Dec 1, 2020

La ciencia y el hombre, 1997

Botanical sciences, Jun 15, 1998

Journal of Applied Ecology, Apr 1, 1987

... LUIS FANJUL AND VICTOR L. BARRADAS ... The site has been previously described in some detail ... more ... LUIS FANJUL AND VICTOR L. BARRADAS ... The site has been previously described in some detail by Fanjul &amp;amp; Barradas (1985). A detailed climatic analysis of the area has been presented elsewhere (De Ita-Martinez 1983). ...

Ciencia - Academia de la Investigación Científica, 1996

ABSTRACT La modelación en Ia ecofisiologia vegetal se ha desarrollado recientemente debido a Ia c... more ABSTRACT La modelación en Ia ecofisiologia vegetal se ha desarrollado recientemente debido a Ia complejidad de los procesos biológicos de las plantas. La meta principal de los modelos generados en esta disciplina de Ia ciencia, es Ia de complementar el entendimiento de las funciones de las plantas, aunque tambien se pueden usar en contextos socio-económicos. En este trabajo se presentan los tipos de modelos que se usan en Ia ecofisiologia vegetal y se discuten sus implicaciones, ventajas y desventajas. Los modelos empíricos se usan con mayor frecuencia cuando se incrementa Ia complejidad de los procesos biológicos, mientras que los mecánicos se usan más en los procesos vegetales físicos (eg evapotranspiración) debido a que Ia complejidad del sistema es menor. Se discute el papel de estos modelos tanto en el método científico, como en una aproximación socioeconómica y se enfatiza su importancia en Ia sociedad. Finalmente, se concluye que las técnicas de modelación deben ser refinadas y que se debe dar mayor atención a los modelos mecánicos para poder entender con mayor precision los procesos ecofisiológicos de las plantas.

Scientia Agropecuaria, Feb 28, 2022

International Journal of Biometeorology, Jul 27, 2021

Phenology has been useful to better understand the climate-vegetation relationship, and it is con... more Phenology has been useful to better understand the climate-vegetation relationship, and it is considered an indicator of climate change impact. Phenological data have been generated through multiple remote sensing techniques and ground-based observations through professional or citizen science. The combination of both techniques is known as cross-scale phenological monitoring. However, no comparative analysis has been carried out to assess the advantages and disadvantages of each of these techniques to characterize the phenological cycle of forest ecosystem species. This work is a content-analysis-based review of scientific literature published between 2000 and 2018 related to cross-scale monitoring methods, to estimate the phenological variation in different forest ecosystems worldwide. For this study, 97 publications related to cross-scale phenological monitoring were selected. We found that 71% of the articles aimed to corroborate the data generated through satellite imagery using surface data from either phenocams, flux towers, or from citizen science networks. More publications were published by authors in the USA (30%), Canada (8%), and China (7%). The most commonly used vegetation index was the normalized difference vegetation index (65%). Some deficiencies in the evaluation of the phenological phases of autumn when compared with surface observations were found. Flux towers and phenocams were included as alternatives for ground-based monitoring. Cross-scale phenological monitoring has the potential to characterize the phenological response of vegetation accurately due to data combinations at two different observation scales. This work contributes to specifying the methodologies used in gathering phenological parameters of the world’s forest ecosystems.

Plant and Soil, Aug 24, 2006

&lt;p&gt;This research is a general reflection of the possible transmission not o... more &lt;p&gt;This research is a general reflection of the possible transmission not only of COVID-19 but of any influenza disease depending on environmental parameters such as solar radiation, air humidity and air temperature (vapor pressure deficit), evoking the Penman-Monteith model regarding the evaporation of the water that constitutes the small water droplets (aerosols) that carry the virus. In this case the evapotranspiration demand of the atmosphere with which it can be deduced that the spread of the disease will be higher in those places with less evaporative demand, that is, high air humidity and / or low temperatures, and / or low radiation intensities, and vice versa. It can also be deduced that the hours of greatest potential contagion are the night hours, while those with the lowest risk are between 2:00 p.m. and 4:00 p.m. On the other hand, in those rooms with low temperatures the contagion would be more effective. So, considering that the drops produced by a sneeze, by speaking or breathing can go beyond two meters away, it is roughly explained that the use of face masks and keeping a safe minimum distance of two meters can limit transmission of viruses and / or infections. However, this practice is not entirely safe as the environment can play an important role. What is recommended to reduce the spread of these pathogens is to produce high evaporative demands: increasing solar radiation, and increasing air temperature and reducing air humidity, which is practice that can be effective in closed rooms.&lt;/p&gt;

Theoretical and Applied Climatology, 1991

International Journal of Biometeorology, 1991

Agricultural and Forest Meteorology, Oct 1, 1986

Revista Mexicana de Ciencias Agrícolas, Oct 1, 2011

Terra Latinoamericana, 2006