Instituto Alexander von Humboldt

Bogotá, Colombia

Instituto Alexander von Humboldt

Bogotá, Colombia
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Aguilar M.,Instituto Alexander von Humboldt | Sierra J.,Catholic University of the East | Ramirez W.,Instituto Alexander von Humboldt | Vargas O.,National University of Colombia | And 7 more authors.
Restoration Ecology | Year: 2015

At an historic moment, when Colombia is emerging from 60 years of armed conflict, the 7-year-old Colombian Network for Ecological Restoration (Red Colombiana de Restauración Ecológica [REDCRE]) has created four subnational nodes, and is actively developing several more. All of this is taking place in the context of the Ibero-American and Caribbean Society for Ecological Restoration (Sociedad Ibero-Americana y del Caribe de la Restauración Ecológica [SIACRE]). In mid-November 2014, over 200 representatives of government agencies, academia, private enterprises, and nongovernmental organizations (NGOs) from the entire country attended a symposium to launch the Antioquia Province node, and take stock and plan the way forward. There are bright prospects of transdisciplinary and public-private collaborations in Colombia for ecological restoration and restoration of natural capital as part of a strategy to transition smoothly to a post-conflict era. We suggest some goals and guidelines to help move forward an ambitious agenda to mainstream ecological restoration. © 2015 Society for Ecological Restoration.

Quiroz L.,Pontifical Xavierian University | Tobon L.,Pontifical Xavierian University | Caycedo P.,Instituto Alexander Von Humboldt | Laverde O.,University of Los Andes, Colombia
2015 20th Symposium on Signal Processing, Images and Computer Vision, STSIVA 2015 - Conference Proceedings | Year: 2015

Studies focused on soundscape are important on biological conservation, because natural sounds are permanent and with dynamic properties, they have been linked to the welfare of the environment and the structure of the landscape. These studies usually analyze the sound in time and frequency domains, with computationally heavy and centralized algorithms. However, new technologies for real time analysis requires distributed algorithms with low computational cost. Hence, the present work evaluates the computational cost of alternative methods with potential applicability in analysis of time-varying signals. The analyzed methods are short time Fourier transform, harmonic expansion, wavelet transform (analytical and non-analytical Morlet, Mexican hat, and Paul) and orthogonal polynomial expansion (Legendre, Chebyshev, and Hermite). A comparison between these methods is presented, in which processing time, memory consumption, quality of reconstruction and grouping index are some of the features selected, resulting in a useful computational cost ranking. The methods are applied to several signals generated with different procedures, such as artificial modulated signals and natural recorded sounds (provided by The Alexander Von Humboldt Institute). In conclusion, Harmonic expansion, Chebyshev expansion, Legendre expansion and Short Time Fourier Transform are the best methods with excellent performance in all features. © 2015 IEEE.

Gonzalez C.,University of Los Andes, Colombia | Paz A.,Instituto Alexander von Humboldt | Ferro C.,Instituto Nacional Of Salud
Acta Tropica | Year: 2013

Visceral leishmaniasis (VL) is caused by the trypanosomatid parasite Leishmania infantum (=Leishmania chagasi), and is epidemiologically relevant due to its wide geographic distribution, the number of annual cases reported and the increase in its co-infection with HIV. Two vector species have been incriminated in the Americas: Lutzomyia longipalpis and Lutzomyia evansi. In Colombia, L. longipalpis is distributed along the Magdalena River Valley while L. evansi is only found in the northern part of the Country. Regarding the epidemiology of the disease, in Colombia the incidence of VL has decreased over the last few years without any intervention being implemented. Additionally, changes in transmission cycles have been reported with urban transmission occurring in the Caribbean Coast. In Europe and North America climate change seems to be driving a latitudinal shift of leishmaniasis transmission. Here, we explored the spatial distribution of the two known vector species of L. infantum in Colombia and projected its future distribution into climate change scenarios to establish the expansion potential of the disease. An updated database including L. longipalpis and L. evansi collection records from Colombia was compiled. Ecological niche models were performed for each species using the Maxent software and 13 Worldclim bioclimatic coverages. Projections were made for the pessimistic CSIRO A2 scenario, which predicts the higher increase in temperature due to non-emission reduction, and the optimistic Hadley B2 Scenario predicting the minimum increase in temperature. The database contained 23 records for L. evansi and 39 records for L. longipalpis, distributed along the Magdalena River Valley and the Caribbean Coast, where the potential distribution areas of both species were also predicted by Maxent. Climate change projections showed a general overall reduction in the spatial distribution of the two vector species, promoting a shift in altitudinal distribution for L. longipalpis and confining L. evansi to certain regions in the Caribbean Coast. Altitudinal shifts have been reported for cutaneous leishmaniasis vectors in Colombia and Peru. Here, we predict the same outcome for VL vectors in Colombia. Changes in spatial distribution patterns could be affecting local abundances due to climatic pressures on vector populations thus reducing the incidence of human cases. © 2013 The Authors.

Cardenas J.C.,University of Los Andes, Colombia | Rodriguez L.A.,Instituto Alexander von Humboldt | Johnson N.,Kenya International Livestock Research Institute
Environment and Development Economics | Year: 2011

The collective action problem around water use and management involves solving both the problems of provision and appropriation. Cooperation in the provision can be affected by the rival nature of appropriation and the asymmetries in access. We report the results of two field experiments conducted in Colombia and Kenya. The irrigation game was used to explore the provision and appropriation decisions under asymmetric or sequential appropriation, complemented by a voluntary contribution mechanism experiment which looks at provision decisions under symmetric appropriation. The overall results were consistent with the patterns of previous studies: the zero contribution hypotheses is rejected whereas the most effective institution to increase cooperation was face-to-face communication, although we find that communication works much more effectively in Colombia than in Kenya. We also find that the asymmetric appropriation did reduce cooperation, though the magnitude of the social loss and the effectiveness of alternative institutional options varied across sites. © Copyright Cambridge University Press 2010.

The hylid frog fauna of the Colombian lowlands east of the Andes consists of 72 or 73 species (one identified only tentatively), comprising about 40% of all frog species of that region and 10% of the total frog fauna known for the country. Most lowland hylids reproduce in lentic waters and few species reproduce in sluggish streams, treeholes, and bromeliads. The tadpoles of 41 species are illustrated in this study, including eight previously unknown and three others never before illustrated.

Boyania colombiana Humberto Mend. (Melastomataceae) is described and illustrated from an area of sandy soils in the department of Caquet, Colombia. It is a disjunct species in a monotypic genus known from the Guayana Shield in Guyana. Boyania colombiana is distinguished from B. ayangannae Wurdack by the shape of the leaf base, the petiole longer than 2 cm, the shortened internodes, and the absence of a dorsal connective appendix. Boyania colombiana is compared to other genera of the tribe Bertolonieae, and the generic position of the new species is discussed. © 2010 Missouri Botanical Garden.

Vallejo M.I.,National University of Colombia | Galeano G.,National University of Colombia | Valderrama N.,Instituto Alexander von Humboldt | Bernal R.,National University of Colombia
Botanical Journal of the Linnean Society | Year: 2016

We describe and discuss palm heart production from wild Euterpe oleracea in Colombia and analyse the social, ecological and trade aspects determining its sustainability. Palm heart is harvested on communal lands by Afro-descendants, who receive US$0.1 per stem. To obtain an income corresponding to a minimum wage, a harvester would have to fell 167 stems per day, i.e. one palm stem every 3 min non-stop over 8 h of work. The pressure of this system leads to over-exploitation of the palm stands, causing local exhaustion of the resource, thus depriving communities of the palm fruit, a vital component of their diet. We evaluated in two harvest scenarios on non-harvested palm populations (annual harvest of either 75 or 50% of the stems), the availability of palm hearts, the number of harvesters per hectare and their net income. We also considered the possibility of doubling or tripling the income of primary producers without affecting the palm stands or increasing the harvesters’ effort. The low market retail price of the final product precludes an improvement in the pay of harvesters or their work conditions. Today many consumers would pay a higher price if it were clear that the product they buy is being produced in a way that is environmentally friendly and socially fair. This information should be provided on the product label and it should be part of communication and education strategies. An alliance of supermarket chains and non-governmental organizations could positively influence attitudes toward the value of this product and help to make consumers aware of their responsibility regarding the fate of the palm and the fairness of its harvest. © 2016 The Linnean Society of London

Gonzalez-Alvarado A.,Instituto Alexander von Humboldt | Vaz-De-Mello F.Z.,Federal University of Mato Grosso
Annales de la Societe Entomologique de France | Year: 2015

The subgenus Hybomidium includes 13 species and one subspecies, of which four are new: Deltochilum (Hybomidium) bezdeki n. sp., D. (H.) carrilloi n. sp., D. (H.) molanoi n. sp., and D. (H.) louzadai n. sp. D. sublaeve Bates 1887 new status and D. panamensis Howden 1966 n. status are elevated from subspecies to species. The synonymies between D. icarus (Olivier 1789) and D. guildingii (Westwood 1835), and between D. orbignyi (Blanchard 1846) and D. chalcea (Buquet 1844) are invalidated, and the synonymy between D. guildingii and D. chalcea new synonymy is proposed; D. amazonicum Bates 1887 is proposed as subspecies of D. orbignyi (D. orbignyi amazonicum n. status). Lectotypes for D. amazonicum, D. chalcea and D. icarus are designated. Descriptions or (re)descriptions, diagnoses, remarks, figures of external morphology and male genitalia, examined material and distribution maps are presented for all species. A key to the species of the subgenus is presented in two languages (English and Spanish). © 2015 Société entomologique de France.

Gonzalez F.A.,Instituto Alexander Von Humboldt | Medina C.A.,Instituto Alexander Von Humboldt
Zootaxa | Year: 2015

The state of knowledge of the genus Ontherus Erichson 1847 in Colombia is reviewed and updated since the revision of the genus by Génier (1996), and the species list for Colombia of Medina et al. (2001). Two new distributional records for Colombia are confirmed; Ontherus politus Génier 1996 and Ontherus gilli Génier 1996. An updated species list of Ontherus for Colombia is presented with comments on the species with doubtful distribution in Colombia. O. felicitae n. sp., a new species from the mexicanus species group, is described from Western Andes of Colombia. Copyright © 2015 Magnolia Press.

The expansion of the agricultural frontier produces fragmented landscapes, habitat decline and loss of diversity. In these landscapes, remnants of riparian vegetation are important elements to maintain biodiversity. We tested the hypothesis that a riparian remnant keeps similar values of dung beetles diversity, compared with a rainforest fragment. Therefore, we expected to find similar values of diversity between the riparian remnant and the adjacent rainforest fragment. The study was carried out in an area of the buffer zone of Natural Paramillo National Park of Córdoba, Colombia. A linear transect including 15 pitfall traps (30 m apart from each) was established at each sampling sites between April and May 2011. We collected 575 specimens, which were distributed among 26 species. The results show a community of dung beetles more equitable and diverse inside remnant forest riparian compared to forest fragment. The forest fragment was dominated by a species Canthon sp.01H that concentrated about 40% of the individuals captured, while in the remnant riparian forest three species were co-dominant Canthon sp.01H, S. moniliatus and Canthidium sp.02H. Beta diversity was <1.4 (maximum beta = 2.0). However, the biggest difference in the assemblies is presented in dominant species in each habitat. Results highlight the importance of riparian vegetation to the diversity of dung beetles to keep particular assemblages differing of the forest fragment mainly in dominant species. The remnant riparian forest was also important to present values of diversity that duplicate the forest fragment diversity and conserves some different species, contributing to the diversity of this landscape. However, this result should be taken with caution due to the particular condition of our study system that involved a comparison between a single fragment and a single riparian remnant. Future studies are needed for further generalization. © 2016, Asociacion Argentina de Ecologia. All rights reserved.

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