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Imagen de apoyo de Áreas naturales de bosque seco tropical en el Valle del Cauca, Colombia: una oportunidad para la restauración

Por: Joel Tupac Otero Ospina | Fecha: 01/01/2017

One of the potential distribution areas for tropical dry forest in Colombia is Cauca River Valley. Intensive agricultural activity in this zone has been one of the main factors causing its degradation since the middle of the 20th century. This study identifies and locates the natural areas that have persisted from 1984-2014 in the Cauca River Valley, in Valle del Cauca Department, using cartographic information and satellite images (Landsat TM5 and OLI). The results indicate that in spite of the 50% reduction in natural areas due to a 72% increase in cultivated areas, 26% of them have persisted since 1984, especially in the dry warm forest of the alluvial plain and in the dry warm forest of the alluvial piedmont, ecosystems of the helobiome biomes of the Valle del Cauca and the tropical alternohydric zonobiome of Valle del Cauca, respectively. The persistent natural areas identified in the time frame represents an opportunity to initiate ecological restoration processes and monitoring of dry forest vegetation and its cover in Valle del Cauca, considering that few remnants still retain structural and functional characteristics of this Biome and the conditions of connectivity between them are deficient.

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

Temas:
Otros

Imagen de apoyo de Aves en páramos de Colombia: características ecológicas de acuerdo a grupos de dieta y peso corporal

Por: Sergio Córdoba-Córdoba | Fecha: 01/01/2016

El páramo es un ecosistema únicamente presente en los Andes tropicales y contiene diferentes tipos de vegetación y sistemas acuáticos. Es utilizado por varias especies de aves, sin embargo, considerar únicamente a las restringidas excluye una gran cantidad de especies. Se realizó un análisis ecológico que incluyó a todas aquellas que lo utilizan, de acuerdo a sus dietas y discontinuidades de peso. Para el análisis se recopilaron las aves registradas en páramos de Colombia y se propone una clasificación en cuatro categorías de presencia. En los páramos de Colombia han sido registradas 207 especies (49 exclusivas, 69 habituales, 65 periféricas y 24 no permanentes). Predominan Thraupidos, Trochilidos, Tyrannidos y Furnariidos. Muchas especies se registran en la cordillera Oriental y menos en la serranía de Perijá y Sierra Nevada de Santa Marta. Hay 22 especies endémicas y 26 casi endémicas de Colombia. Predominan las aves pequeñas, consumidoras de insectos e invertebrados pequeños; cerca de la mitad consumen otro tipo de alimentos (néctar y frutos, y menor proporción semillas, vertebrados y carroña). Las especies más pesadas consumen vertebrados y carroña y recursos acuáticos. Es necesario evaluar algunas especies para conocer su permanencia en los páramos, al igual que sus abundancias y uso de recursos.

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

Temas:
Otros

Imagen de apoyo de Diversidad y recambio de especies de anfibios y reptiles entre coberturas vegetales en una localidad del valle del Magdalena medio, departamento de Antioquia, Colombia

Por: Andrés Aponte-Gutiérrez | Fecha: 01/01/2017

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 Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Leucismo en Astroblepus ubidiai (Pellegrin 1931; Astroblepidae: Siluriformes), de la provincia de Imbabura, Ecuador

Por: Jonathan Valdiviezo-Rivera | Fecha: 01/01/2016

The leucismo is an aberration in pigmentation, resulting from a genetic abnormality and occurs in all vertebrate groups in which the fish are included. In Ecuador, it has not reported such anomalies in fish. Is presented for the first time a case of partial leucismo in an individual of Andean Catfish (Astroblepidae), observed in a spring located near the Lake San Pablo Canton Otavalo, Imbabura Province, Ecuador.

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

Temas:
Otros

Imagen de apoyo de Hifomicetos ingoldianos del río Frío (Floridablanca), Santander, Colombia

Por: Eliana X. Narváez-Parra | Fecha: 01/01/2017

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 Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Banco de semillas de retamo espinoso Ulex europaeus L. en bordes del matorral invasor en un ecosistema zonal de bosque altoandino, Colombia

Por: Korina Ocampo-Zuleta | Fecha: 01/01/2017

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 Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Hormigas en cultivos de naranja (Citrus sinensis L. Osbeck) de la costa Caribe de Colombia

Por: Ángela María Arcila Cardona | Fecha: 01/01/2017

This article describes the database of the ant fauna associated with orange crops on the Caribbean coast of Colombia. The study was carried in the departments of Bolivar, Cordoba, Cesar and Magdalena, in crops of 38 farms in 13 municipalities. In all cultivations, the ants were collected by transects of 50m each with five sampling stations separated by 10 m, at each one three sets of sampling techniques were applied: direct capture (manual), pitfall traps and Winkler sacks. A total of 3119 samples were obtained, distributed into eight subfamilies, 44 genera and 122 species. As expected Myrmicinae subfamily was the one that presented the highest richness (65 species) and capture rate (63,45%). The two most frequent were Ectatomma ruidum and Crematogaster abstinens appearance with a percentage of 13,34% and 8,62% respectively. The database reflects a great diversity in orange crops with a large presence of groups considered important as biological controls including hunting ants and cryptic myrmicines.

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

Temas:
Otros

Imagen de apoyo de Mammals of Colombia deposited at the Zoologische Staatssammlung Muenchen, Germany

Por: Héctor E. Ramírez-Chaves | Fecha: 01/01/2016

The Zoologische Staatssammlung Muenchen (ZSM), Germany, possesses an historical value because is the depositary of important specimens that were used in the description of different species, especially from South America. Unfortunately, there is not available information about the mammals of Colombia housed at this collection. For this, 33 specimens from Colombia belonging to six orders, 14 genus, and 17 species were reviewed. Cranial and external measurements are given, as well as information of collectors and localities. Of these specimens, 23 were captured in Northern Colombia and imported to Germany to a pet store between 1954 and 1966. Due the difficulties to access to information of mammals from Colombia in European museums and collections, the information summarized here may be useful for people interested in these species.

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

Temas:
Otros

Imagen de apoyo de La avifauna actual del lago de Tota, Boyacá (Colombia): área importante para la conservación de las aves

Por: Johana Edith Zuluaga-Bonilla | Fecha: 01/01/2017

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 Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Registros recientes de los puercoespines, género Coendou (Mammalia: Erethizontidae) para el departamento de Córdoba, Colombia

Por: Héctor E. Ramírez-Chaves | Fecha: 01/01/2016

Recent records of porcupines, Coendou quichua and Coendou prehensilis are reported for the department of Córdoba, in the Caribbean region of Colombia. These are from the southern part of the department, from remote regions and the buffer area of the Paramillo National Nature Park. The locality reported here is the seventh verified for the country. Illegal trafficking of one individual of C. prehensilis was observed and comments on its use and threats it faces on a national level are given.

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

Temas:
Otros