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Por: Diana Carolina Macana García | Fecha: 2017

Lake Tota is at 3015 m a.s.l in the eastern Andean cordillera of Colombia. It was declared an Important Bird area - IBA, because it is a strategic breeding area for endemic and threatened species and for its large concentration of resident and migratory waterfowl species. This publication provides a current list of birds, based on direct observations reported by authors from 2003 to 2016. These records were analyzed and compared with historical published data, we present an analysis of five conservation priority species and point out the need for citizen participation to create a civic movement calling attention to the importance of this aquatic ecosystem to the environmental government agencies negative ecological impacts that have been afflicting this aquatic ecosystem for more than 60 years ago, and to insist that it be designated as a RAMSAR site.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Aves
Otros

Por: Jairo Solorza-Bejarano | Fecha: 2017

The seed density of Ulex europaeus was established on borders of invasive scrub thickets to the south of the Eastern Hills of Bogota. Through the direct counting method, seed abundance was established at six sampling points in an altitudinal gradient between 2,300 and 3,200 meters altitude, and for four soil depth ranges of 0 to 20 cm. Variable seed densities were established for the six sampling points between 109 and 3.384 seeds m-2. With regard to depth, the highest seed density was in the range of 0 to 5 cm for all sites sampled. Among the sampling points, significant differences were found in the number of seeds at different altitudes (p = 0.4159) and depth ranges evaluated (p=0.3919). There is a high potential at the edges of scrub for the extension of the invaded areas, by activation of the seed bank of the invasive species, suggesting the need for a priority strategy for the control of these border areas in the framework of ecological restoration processes in high Andean ecosystems.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

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Otros

Por: Andrés Aponte-Gutiérrez | Fecha: 2017

From December 2012 and January 2013 a survey of the herpetofauna diversity was made in forest remnants, farms, open areas, and vegetation around wetlands at a locality in the middle Magdalena River valley, department of Antioquia, Colombia. We recorded 27 amphibian and 36 reptile species. Three of the amphibian species are endemic to Colombia and one is considered threatened; one of the reptile species is endemic to Colombia, and three are categorized as threatened. The species diversity of amphibians and reptiles did not differ significantly between forest and farming areas, but it was higher than in open areas and vegetation associated with wetlands. The species turnover between these two groups of vegetation coverages was higher in amphibians than in reptiles. This differential species turnover level suggests that forest amphibians are more susceptible than the reptiles to deforestation, possibly due to their high dependence of moist microhabitats. Since most forests in the Middle Magdalena River valley of Colombia have been deforested, the conservation of forest remnants that still persist is a priority.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

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Otros

Por: Andrea Villalba | Fecha: 2017

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

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Otros

Por: Clara L. Matallana-Tobón | Fecha: 2017

This study was conducted with the support of the Young Researchers and Innovators Program 2012- 2013 of Colciencias. The aim of the study was to develop a qualitative analysis of the ecosystem services provided by the land covers within the different categories of protected areas in the Orinoco basin. To achieve this goal, a matrix was constructed according to the capacities of the different land covers to provide ecosystem services and their respective conservation categories were analyzed. A survey of experts working on protected areas was also performed. As results was obtained for each protected area management category the number of hectares and the type of land cover and ecosystem were identified. Of the total number of surveys sent to experts, 19 were completed and additional information on 3 private reserves was obtained from interviews with the owners. As conclusions, the region has a variety of land covers with different capacities to provide regulation, provision and cultural ecosystem services. However, a complete analysis would require field work in each area in order to verify the matrix of provision capacities of ecosystem services. The information hereby presented may contribute to the effective management of the protected areas.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

Temas:
Otros

Por: Javier H. Jerez-Jaimes | Fecha: 2017

The diversity of Ingoldian hyphomycetes in Colombia is known from three studies that reported in total 18 species of these fungi. For eastern Colombian there are no records of these microorganisms. In this study foam samples were collected in the Frio River drainage in the municipality of Floridablanca (Santander) in October 2013 and September 2014. In this inventory 23 hyphomycetes taxa are reported of which 20 are new records for Colombia. Clavatospora tentacula was found in both sample periods. A marked decline in species richness related to the reduction of rainfall in the year 2014 was observed.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

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Otros

Por: Luz Fernanda Jiménez-Segura | Fecha: 2016

Changes in the biota inhabiting the streams downstream of dams have been the subject of numerous studies but few have focused on recovery gradients downstream of the dam or the influence of seasonality on the pulse of the flow in regulated streams. Since 2000 the hydro-power company Isagen SA E.S.P. has been monitoring some emerging characteristics of the fish community in the lower basin of La Miel River (Magdalena River Basin) downstream of the dam to document the response of the fish fauna to new environmental conditions. Based on this monitoring, we tested the hypothesis that there would be a gradient of recovery in the fish assemblage characteristics along the longitudinal axis, downstream from the turbine’s output to its mouth in the Magdalena River. The highest values observed in the dominance index were a result of the arrival of migratory species to the site of the water discharge from the dam during low water period. Finally there is a need to weigh alternative locations of a dam taking into consideration the possibility that downstream tributaries can diminish the impact of the dam and hydropower plant operation.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

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Otros

Por: Yimy Herrera-Martínez | Fecha: 2016

Planktonic bacteria are involved in the process of recycling energy and take part in the bio-geochemical cycles of carbon, nitrogen and phosphorus by the processes of mineralization and transformation from inorganic compounds to organic matter. Thus these compounds are available in higher trophic levels. Although we know the importance of these bacteria, the knowledge is still low about the processes particularly how are organized in the Andes trop-ical ecosystems. The aim of this study was to carry out the characterization of planktonic bacteria: biomass, abundance and morphology in the Andean wetlands of the Eastern Cordillera. Triplicate samples were taken from surface, deep and littoral water from three lakes (La Cristalina, Laguna Negra, and Laguna Verde) in Boyacá. We found low abundance and biomass but these are within the range for oligotrophic lakes. The bacillary forms were most common in these ecosystems. Variations in abundance were found in relation to the season, being higher during the dry season.

Fuente: Instituto de Investigación de Recursos Biológicos Alexander von Humboldt Formatos de contenido: Artículos

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Otros

Por: Pedro Manuel Luengo Gutiérrez | Fecha: 01/01/2023

Fuente: Icanh - Fronteras de la Historia Formatos de contenido: Artículos

Por: Lireida José Sánchez Torres | Fecha: 01/01/2023

El presente artículo analiza una supuesta “peste” que tuvo lugar en Cartagena en 1696, a partir de un expediente que da cuenta del suceso y la conmoción que causó en ese puerto y en la capital del virreinato. Si bien no existe consenso sobre el tipo de enfermedad y el impacto mortal que tuvo en la sociedad cartagenera, este trabajo indaga acerca de varias posibilidades y se presenta como una incipiente veta de análisis para futuras investigaciones. En este sentido, el trabajo plantea aportes sobre el estudio de las epidemias en el virreinato de la Nueva Granada, específicamente en Cartagena de Indias, algunas de las cuales no s e encuentran bien documentadas o estudiadas por la historiografía. Asimismo, por medio de los testimonios de la época, se intenta adentrarse en el rol que desempeñaban el rumor y el miedo en estas situaciones, a la vez que se rastrean las rutas de contagio entre Cartagena y Santafé.

Fuente: Icanh - Fronteras de la Historia Formatos de contenido: Artículos

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Otros