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421 resultados encontrados para: AUTOR: García, J. A.
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Resumen en: Español | Inglés |
Resumen en español

El objetivo del estudio fue determinar el valor nutritivo, la fermentación ruminal y la producción de metano in vitro del follaje de especies arbóreas y arbustivas con potencial forrajero como estrategias de alimentación en época de secas y mitigación de las emisiones de metano. El líquido ruminal fue extraído por medio de una sonda esofágica. Se utilizó un diseño en bloques repetidos en el tiempo. El contenido de proteína cruda (PC) y fibra detergente neutro y acida fluctuaron de 6.14% a 21.78%, 44.34% a 77.43% y 16.12% a 49.53% de materia seca (MS). No se encontró diferencia en el volumen máximo de gas (p > 0.05). La degradabilidad fue diferente, observando la mejor en Tithonia diversifolia (760.40 g/kg de MS), Morus alba (800.66 g/kg de MS) y Hibiscus rosa-sinensis (800.16 g/kg de MS), mientras que la más baja fue Megatryrsus maximus (390.40 g/kg de MS y 287.40 g/kg de materia orgánica (MO)) (p < 0.05). No se observó diferencia en la producción de metano (CH4) (p > 0.05). Se concluye que L. leucocephala, P. piscipula, B. alicastrum y G. ulmifolia, T. diversifolia y M. alba tienen un alto potencial para ser incluidos en la dieta de rumiantes como fuentes de proteína en época de secas y estrategias para mitigar las emisiones de metano.

Resumen en inglés

The objective of the study was to determine the nutritional value, ruminal fermentation, and in vitro methane production of foliage of tree and shrubs species with forage potential as feeding strategies in dry season and mitigation of methane emissions. The rumen liquor was taken by an esophageal tube. A repeated block design overtime was used. The content of crude protein (CP) and neutral and acid detergent fiber ranged from 6.14% to 21.78%, 44.34% to 77.43% and 16.12% to 49.53% of dry matter (DM). No difference was found in the maximum volume of gas (p > 0.05). The degradability was different among species, and it was higher for Tithonia diversifolia (760.40 g/kg DM), Morus alba (800.66 g/kg DM) and Hibuscus rosa-sinensis (800.16 g/kg DM), whilst the lower was for Megathyrsus maximus (390.40 g/kg DM and 287.40 g/kg organic matter (OM)) (p < 0.05). No difference in methane (CH4) production was observed (p > 0.05). It is concluded that L. leucocephala, P. piscipula, B. alicastrum and G. ulmifolia, T. diversifolia, and M. alba have a high potential to be included in the ruminant diet as sources of protein in the dry season and strategies to mitigate methane emissions


2.
Artículo
Desarrollo oogénico y ciclo gonotrófico de Aedes aegypti y Aedes albopictus en laboratorio
Casas Martínez, Mauricio (autor) ; Tamayo Domínguez, Rodrigo (autor) ; Bond Compeán, Juan Guillermo (autor) ; Rojas, Julio C. (autor) ; Weber, Manuel (autor) ; Ulloa García, Armando (autor) ;
Disponible en línea
Contenido en: Salud Pública de México Volumen 62, número 4 (julio-agosto de 2020), p. 372-378 ISSN: 0036-3634
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Resumen en: Español | Inglés |
Resumen en español

Objetivo. Determinar el tiempo de desarrollo oogénico y del ciclo gonotrófico de Aedes aegypti y Aedes albopictus en laboratorio. Material y métodos. Hembras de Ae. aegypti y Ae. albopictus alimentadas con sangre fueron disecadas cada cuatro horas para determinar el estado de desarrollo folicular, según los estadios de Christophers. Resultados. El tiempo mínimo de maduración del oocito en Ae. aegypti y Ae. albopictus fue de 64-82 h y 52-64 h post-alimentación, respectivamente. El ciclo gonotrófico de Ae. aegypti (3.7-4.2 d) fue mayor que el de Ae. albopictus (3.2-3.7 d). La longitud folicular presentó diferencias significativas entre las especies en los estadios de Christophers 2” y 5, mientras que la amplitud folicular fue diferente entre ambos mosquitos en los estadios 2”, 3 y 4. Conclusiones. El estudio proporcionó nueva evidencia sobre la estrategia reproductiva de las hembras de Ae. aegypti y Ae. albopictus que coexisten en la región neotropical de México.

Resumen en inglés

Objective. To determine the time of oogenic development and the length of the gonotrophic cycle of Ae. aegypti and Ae. albopictus in laboratory. Materials and methods. Bloodfed females of Ae. aegypti and Ae. albopictus were dissected every 4 h to determine the development status of the follicles according to the Christophers’ stages. Results. The minimum time of oocyte maturation in Ae. aegypti and Ae. albopictus was 64-82 h and 52-64 h post-feeding, respectively. We found that the gonotrophic cycle of Ae. aegypti (3.7-4.2 d) is longer than that of Ae. albopictus (3.2-3.7 d). The follicle length showed significant differences between species at Christophers’ stages 2” and 5, whereas follicle amplitude was different between the two mosquitoes at stages 2”, 3 and 4. Conclusions. The study provided new evidence on the reproductive strategies of Ae. aegypti and Ae. albopictus females that coexist in the Neotropical region of Mexico.


3.
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A geographical cline in craniofacial morphology across populations of Mesoamerican lake-dwelling fishes
Powers, Amanda K. (autora) ; Garita Alvarado, Carlos A. (autor) ; Rodiles Hernández, María del Rocío (autora) (1956-) ; Berning, Daniel J. (autor) ; Gross, Joshua B. (autor) ; Ornelas García, Claudia Patricia (autora) ;
Disponible en línea
Contenido en: Journal of Experimental Zoology. Part A: Ecological and Integrative Physiology Vol. 333, no 3 (March 2020), p. 171-180 ISSN: 2471-5646
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Resumen en: Inglés |
Resumen en inglés

Together, the complex geological history and climatic diversity of Mesoamerica create a rich source of biodiversity from which evolutionary processes can be studied. Here, we discuss highly divergent morphs of lake‐dwelling fishes distributed across Mexico and Central America, originally recognized as members of different genera (Astyanax and “Bramocharax”). Recent phylogenetic studies, however, suggest these morphs group within the same genus and readily hybridize. Despite genetic similarities, Bramocharax morphs exhibit stark differences in cranial shape and dentition. We investigated the evolution of several cranial traits that vary across morphs collected from four lakes in Mexico and Nicaragua and discovered an ecomorphological cline from northern to southern lakes. Northern populations of sympatric morphs exhibit a similar cranial shape and tooth morphology. Southern populations of Bramocharax morphs, however, showed a larger disparity in maxillary teeth, length and frequency of unicuspid teeth, an elongated snout, and a streamlined cranium compared to Astyanax morphs. This divergence of craniofacial morphology likely evolved in association with differences in trophic niches. We discuss the morphological differences across the four lake systems in terms of geological history and trophic dynamics. In summary, our study suggests that Bramocharax morphs are likely locally adapted members derived from independent Astyanax lineages, highlighting an interesting parallel evolutionary pattern within the Astyanax genus.


4.
- Artículo con arbitraje
Resumen en: Inglés |
Resumen en inglés

The objective of this study was to evaluate the effects of inclusion of tropical tree foliage on intake, digestibility, and nitrogen balance in sheep fed with a diet based on fresh chopped Pennisetum purpureum. Four male Pelibuey sheep were used, with an average live weight of 22 ± 1.5 kg, distributed in a (4 × 4) Latin square design. Treatments were P. purpureum (T1), P. purpureum + Brosimum alicastrum (T2), P. purpureum + Guazuma ulmifolia (T3), and P. purpureum + Piscidia piscipula (T4). Tree foliage was incorporated into the ration at a proportion rate of 300 g/kg of dry matter (DM). Intake, digestibility, and nitrogen balance were measured during 24 h periods for 7 days. DM intake, organic matter (OM), and crude protein (CP) intakes were not affected (P > 0.05) by including tree foliage (an average of 892.7, 784.2, and 88.9 g/day, respectively). OM and CP digestibility was similar among treatments (P > 0.05). Nevertheless, digestibility of DM and NDF was lower (P < 0.05) in T2 and T4 than in T1 (DM = 570, 560, and 662.5 g/kg; NDF = 687.0, 650.9, and 772.1 g/kg, respectively). We conclude that providing 30% of the ration in DM of foliage of B. alicastrum, G. ulmifolia, and P. piscipula improves CP intake and reduces NDF intake, thereby improving digestibility of OM, CP in sheep, which indicates that the foliage of these tree species may be used as a protein supplement during the dry season in tropical regions.


5.
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Precipitous decline of white-lipped peccary populations in Mesoamerica
Thornton, Daniel (autor) ; Reyna Hurtado, Rafael Ángel (autor) ; Perera Romero, Lucy (autora) ; Radachowsky, Jeremy (autor) ; Hidalgo Mihart, Mircea Gabriel (autor) ; García Anleu, Rony (autor) ; McNab, Roan (autor) ; Mcloughlin, Lee (autor) ; Foster, Rebecca (autora) ; Harmsen, Bart (autor) ; Moreira Ramírez, José Fernando (autor) ; Diaz Santos, Fabricio (autor) ; Jordan, Christopher A. (autor) ; Salom Pérez, Roberto (autor) ; Meyer, Ninon France Victoire (autor) ; Castañeda, Franklin (autor) ; Elvir Valle, Fausto Antonio (autor) ; Ponce Santizo, Gabriela (autora) ; Amit, Ronit (autora) ; Arroyo Arce, Stephanny (autora) ; Thomson, Ian (autor) ; Moreno, Ricardo (autor) ; Schank, Cody J. (autor) ; Arroyo Gerala, Paulina (autora) ; Bárcenas, Horacio V. (autor) ; Brenes Mora, Esteban (autor) ; Calderón, Ana Patricia (autora) ; Cove, Michael V. (autor) ; Gómez Hoyos, Diego (autor) ; González Maya, José F. (autor) ; Guy, Danny (autor) ; Hernández Jiménez, Gerobuam (autor) ; Hofman, Maarten (autor) ; Kays, Roland (autor) ; King, Travis (autor) ; Martinez Menjivar, Marcio Arnoldo (autor) ; Maza, Javier de la (autor) ; León Pérez, Rodrigo (autor) ; Ramos, Víctor Hugo (autor) ; Rivero Hernández, Crysia Marina (autora) ; Romo Asunción, Sergio (autor) ; Juárez López, Rugieri (autor) ; Jesús de la Cruz, Alejandro (autor) ; De la Torre, Jesús Antonio (autor) ; Towns, Valeria (autora) ; Schipper, Jan (autor) ; Portillo Reyes, Hector Orlando (autor) ; Artavia, Adolfo (autor) ; Hernández Pérez, Edwin Luis Oswaldo (autor) ; Martínez, Wilber (autor) ; Urquhart, Gerald R. (autor) ; Quigley, Howard (autor) ; Pardo, Lain E. (autor) ; Sáenz, Joel C. (autor) ; Sanchez, Khiavett (autora) ; Polisar, John (autor) ;
Contenido en: Biological Conservation Vol. 242, no. 108410 (2020), p. 1-12 ISSN: 0006-3207
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Resumen en: Inglés |
Resumen en inglés

Large mammalian herbivores are experiencing population reductions and range declines. However, we lack regional knowledge of population status for many herbivores, particularly in developing countries. Addressing this knowledge gap is key to implementing tailored conservation strategies forspecies whose population declines are highly variable across their range. White-lipped peccaries (Tayassupecari) are important ecosystem engineers in Neotropical forests and are highly sensitive to human disturbance. Despite maintaining a wide distributional range, white-lipped peccaries are experiencing substantial population declines in some portions of their range.We examined the regional distribution and population status of the species in Mesoamerica. We used a combination of techniques, including expert-based mapping and assessment of population status, and data-driven distribution modelling techniques to determine the status and range limits of white-lipped peccaries. Our analysis revealed declining and highly isolated populations of peccaries across Mesoamerica, with a range reduction of 87% from historic distribution and 63% from current IUCN range estimates for the region. White-lipped peccary distribution is affected by indices of human influence and forest cover, and more restricted than other sympatric large herbivores, with their largest populations confined to transboundary reserves. To conserve white-lipped peccaries in Mesoamerica, transboundary efforts will be needed that focus on both forest conservation and hunting management, increased cross-border coordination, and reconsideration of country and regional conservation priorities. Our methodology to detail regional white-lipped peccary status could be employed on other poorly-known large mammals.


6.
Capítulo de libro
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Socio-environmental regimes in natural protected areas: a case study in La Sepultura Biosphere Reserve
Meza Jiménez, Amayrani (autora) ; Parra Vázquez, Manuel Roberto (autor) ; García Barrios, Luis Enrique (autor) ; Verschoor, Gerard (autor) ; Estrada Lugo, Erin Ingrid Jane (autora) (1959-) ;
Contenido en: Socio-environmental regimes and local visions: transdisciplinary experiences in Latin America / Minerva Arce Ibarra, Manuel Roberto Parra Vázquez, Eduardo Bello Baltazar, Luciana Gomes de Araujo, editors Cham, Switzerland, German : Springer Nature Switzerland AG, 2020 páginas 291-312 ISBN:978-3-030-49767-5
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In this chapter, we analyze the reasons why local socio-environmental systems have met in a limited way the purpose of balancing conservation with development in the Upper Basin of the Tablón River (UBTR), located in La Sepultura Biosphere Reserve (SEBIRE). The study used a transdisciplinary exercise which conceives the Local Socio-Environmental Systems (LSES) as complex and adaptive systems, in which four subsystems interact: (i) the local regime, (ii) the landscape, (iii) the agrarian system, and (iv) the territorial action group. Two common property holdings (“ejidos”) were studied with the case study method. The four subsystems were analyzed through participatory and qualitative research. The results indicated: (a) the local regime imposes norms that limit the decision-making capacity of local actors and its compensatory payments generate dependency and a reactive attitude; (b) the setback of forest frontiers has remained relatively stable due to SEBIRE environmental standards, but natural capital is increasingly vulnerable to socio-environmental disturbances; (c) domestic units (DUs) have little capacity to respond to environmental and market changes; their development is restricted by the geographical, social, and economic conditions of the basin; some producers are unable to cover their production costs and their limited resources barely reach the minimum welfare line; and (d) in the UBTR there are important socio-environmental innovation processes that have generated adaptive management alternatives, but these still face significant challenges at the basin level. In conclusion, the LSES of the UBTR has restrictions on its four components and has not reached the capacity to be socially reproduced. In these LSES, the local regime has promoted an economic model and territorial management mechanisms that have made it environmentally and economically vulnerable.


7.
Capítulo de libro
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Traditional knowledge in the Colombian Amazon: tensions between indigenous territorial autonomy and environmental governance
De La Cruz Nassar, Pablo Emilio (autor) ; Bello Baltazar, Eduardo (autor) (1960-) ; Acosta Muñoz, Luis Eduardo (autor) ; Estrada Lugo, Erin Ingrid Jane (autora) (1959-) ; Arce Ibarra, Ana Minerva (autora) ; García Jiménez, Luis Enrique (autor) ;
Contenido en: Socio-environmental regimes and local visions: transdisciplinary experiences in Latin America / Minerva Arce Ibarra, Manuel Roberto Parra Vázquez, Eduardo Bello Baltazar, Luciana Gomes de Araujo, editors Cham, Switzerland, German : Springer Nature Switzerland AG, 2020 páginas 27-47 ISBN:978-3-030-49767-5
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The present study aims to analyze the role of traditional knowledge in territorial autonomy and environmental governance, as well as the level of interest of different indigenous and non-indigenous actors in the southern Colombian Amazon in applying traditional knowledge to public policy. Using the theoretical approaches of political ecology as well as a qualitative method, we describe a multidisciplinary project developed and implemented to incorporate knowledge systems of indigenous peoples of the Colombian Amazon into environmental policy. The results present an analysis of arguments by indigenous organizations, researchers, and government environmental agency administrators for and against using traditional knowledge to address the global ecological crisis. Through interviews and reports systematized by researchers and local collaborators within the project, we discuss conflicts that emerge when attempts are made to apply traditional knowledge in asymmetrical spaces of power. This includes responses by local residents to the global governance regime, which imposes policies regarding traditional knowledge in indigenous territories, and the possible repercussions of environmental policies on indigenous autonomy regimes in territories considered to be ancestral by indigenous peoples. We conclude that indigenous communities and organizations are more willing to apply traditional knowledge to public policy when the process is oriented toward strengthening their territorial and environmental autonomy than when external actors attempt to use this knowledge to promote global regulatory regimes that are beyond the control of local actors.


8.
Tesis - Maestría
Abejas nativas y educación ambiental: cambiando actitudes hacia la naturaleza / Patricia García Rosas
García Rosas, Patricia (autora) ; Damon, Anne Asbhy (directora) ; Ramos Muñoz, Dora Elia (asesora) ; Mesa Jurado, María Azahara (asesora) ;
Villahermosa, Tabasco, México : El Colegio de la Frontera Sur , 2019
Clasificación: TE/595.799097263 / G3
Bibliotecas: Tapachula
Cerrar
SIBE Tapachula
ECO020013843 (Disponible)
Disponibles para prestamo: 1
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Índice | Resumen en: Español |
Resumen en español

Esta investigación se realizó en la ranchería Guineo 1ª Sección municipio Centro del estado de Tabasco en el año 2018. El objetivo fue probar los hoteles para abejas como una herramienta en una estrategia de educación ambiental basada en la enseñanza situada, con el propósito de crear conocimientos sobre las abejas nativas de la región y cambiar las actitudes de los estudiantes hacia éstas y hacia el medio natural, mediante la generación de experiencias significativas y afinidad emocional hacia las abejas nativas. Dicha estrategia educativa se dirigió a 30 estudiantes de quinto grado de la Primaria Rural Federal Ignacio Zaragoza. Se realizó un diagnóstico inicial de las actitudes y conocimientos de los estudiantes y una evaluación final después de la estrategia educativa. Se trabajó con ellos durante 6 meses, en los cuales adquirieron conocimientos y habilidades cognitivas que se relacionan con su contexto de vida y que tienen diferentes usos dentro de éstas. Se logró un cambio significativo en las actitudes de los estudiantes hacia las abejas nativas y hacia el entorno natural. Se logró la creación de nuevos conocimientos por parte de los estudiantes. No se encontró relación entre los conocimientos y la observación de los hoteles con el cambio de actitudes, pero se encontró una correlación positiva entre el cambio de actitudes hacia las abejas y el cambio de actitudes hacia la naturaleza.

Índice

Resumen
Introducción
Antecedentes
La educación ambiental
Experiencia y enseñanza situada
La edad escolar
Actitudes, biofilia y biofobia
Las abejas nativas
Hoteles para abejas
Niñas, niños y abejas
Tabasco, Centro
Justificación
Pregunta de investigación
Hipótesis
Objetivos
Objetivo general
Objetivos específicos
Métodos
Participantes
Diseño del estudio
A. Diseño y prueba de los hoteles para abejas
B. Diagnóstico
C. Diseño y aplicación de la estrategia educativa
• Patio de trabajo
D. Evaluación de la estrategia educativa
E. Evaluación de las actividades implementadas después de la estrategia educativa
F. Sistematización y análisis de los resultados
Resultados
Diagnóstico
Entrevista
Cuestionario de la tipología de Kellert para la medición de la biofilia y biofobia
Estrategia educativa
Patio de trabajo y hoteles para abejas
Evaluación de la estrategia educativa
Cuestionario de biofilia y biofobia
Entrevista final
Cambio de actitudes hacia la naturaleza
Cambio de actitudes hacia las abejas nativas
Evaluación de las actividades implementadas después de la estrategia educativa
Discusión
Conclusión
Literatura citada
Anexos


9.
- Artículo con arbitraje
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Analysis of the contribution of landscape attributes on the genetic diversity of Artibeus jamaicensis Leach, 1821
Leiva González, Elida María ; Navarrete Gutiérrez, Darío Alejandro (coaut.) ; Ruiz Montoya, Lorena (coaut.) (1964-) ; Santos Moreno, Antonio (coaut.) ; Kraker Castañeda, Cristian (coaut.) ; García Bautista, Maricela (coaut.) ;
Contenido en: Mammal Research Vol. 64, no. 2 (April 2019), p. 223–233 ISSN: 2199-241X
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It is commonly assumed that bats, due to their flight capacity, are not affected by landscape attributes across small geographic extensions. However, recent studies with phyllostomids have found evidence of negative responses, such as decreasing genetic diversity with decreasing forest amount, specifically in areas dominated by agricultural land. The purpose of this study was to evaluate if landscape composition and configuration could be influencing the genetic diversity of a common frugivorous bat: Artibeus jamaicensis. We worked in an area characterized by the presence of extensive agricultural land, with a trend towards open spaces of high contrast with forests. Through mtDNA control region sequences, we inferred high levels of genetic diversity in the surveyed landscapes. In order to determine a possible relationship between genetic diversity and landscape attributes, we employed a multivariate exploratory analysis that allowed us to determine the independent contribution of each variable, in a hierarchical model. We found a negative relationship between genetic diversity and total forest edge, which is a variable that reflects the degree of fragmentation. This procedure can be implemented in population genetics, allowing the incorporation of spatially explicit variables.


10.
- Artículo con arbitraje
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Assessment of browsed plants in a sub-tropical forest frontier by means of fuzzy inference
Dechnik Vázquez, Yanus Andrés (autor) ; García Barrios, Luis Enrique (autor) ; Ramírez Marcial, Neptalí (autor) (1963-) ; van Noordwijk, Meine (autor) ; Alayón Gamboa, José Armando (autor) ;
Contenido en: Journal of Environmental Management Vol. 236 (April 2019), p. 163-181 ISSN: 0301-4797
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Browsing of forest frontiers by cattle in sub-tropical landscapes is detrimental to ecosystem health, but essential to smallholder livelihoods. We described a silvopastoral landscape, searching for browsed plants to assess how much of the forest is actually used for this end, and also searching for potential new useful species for silvopastoral purposes. The first objective was accomplished through a floristic description, making observations of individuals with browsing marks. Information from interviews, bromatological analyses and vegetative propagation tests further complemented this information to achieve the second objective. We classified the results using Fuzzy Inference Systems (FISs). A great variety of nutritious browsed plants was found, distributed across various types of vegetation, growth habits and taxonomic groups: forest frontiers already are like silvopastoral systems. Various plants like Acalypha leptopoda, Montanoa tomentosa and Verbesina perymenioides are interesting prospects for further intensification of silvopastoral systems.