Browsing by Autor "Stephan Beck"

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A New Miconia (Melastomataceae) from Bolivia, with Remarks on Angular-Branched Species in the Andes
(Missouri Botanical Garden Press, 2003) Susanne S. Renner; Stephan Beck
A new species of Melastomataceae from Bolivia is described, illustrated, and placed in a phenetic context within Miconia, a genus of 1000 species and about 2000 published names.Miconia quadrialata is readily distinguished from its con¬ geners by two-colored leaves and sharply four-an¬ gular and winged branchlets.A search for quadrangular-branched miconias revealed that 12 of 15 such species (in four sections), including the new species, occur in cloud forest in the Andes, raising the question of the adaptive significance of qua¬ drangular branchlets.
A Revision of Bidens (Asteraceae: Coreopsideae) from Bolivia
(Missouri Botanical Garden, 2024) Mabel A. Lizarazu; Stephan Beck; Alfredo Fuentes; Susana E. Freire
The genus Bidens L. is the largest genus of the Coreopsideae that comprises about 280 species with a global distribution in tropical and temperate climates. An account of the 12 species and three varieties of Bidens occurring in Bolivia is provided, i.e., B. andicola Kunth var. andicola, B. andicola var. heterophylla Kuntze, B. aurea (Aiton) Sherff, B. cynapiifolia Kunth, B. exigua Sherff, B. gardneri Baker, B. herzogii (Sherff) D. J. N. Hind, B. mandonii (Sherff) Cabrera, B. pilosa L., B. pseudocosmos Sherff, B. squarrosa Kunth, B. subalternans DC. var. subalternans, B. subalternans var. simulans Sherff, B. tenera O. E. Schulz, and B. triplinervia Kunth var. macrantha (Wedd.) Sherff. The following three taxa are placed in synonymy: B. buchtienii Sherff is synonymized under B. andicola var. heterophylla; and B. andicola var. tarijensis Sherff and B. andicola f. dissecta Sherff under B. triplinervia var. macrantha. Diodonta coronata (L.) Nutt. is selected as the generitype of Diodonta Nutt. (= Bidens), and 23 lectotypes are designated: one for B. andicola, one for B. andicola var. heterophylla, one for B. gardneri, nine for names applicable to B. pilosa, one for B. pseudocosmos, five for names applicable to B. squarrosa, one for a name applicable to B. tenera, five for names applicable to B. triplinervia var. macrantha; and an epitype is proposed for the name B. odorata Cav. Four taxa are excluded from Bolivia, i.e., B. bipinnata L., B. reptans (L.) G. Don, B. rubifolia Kunth, and B. grandiflora Balb. var. longiloba Kuntze for which specimens have not been traced that confirmed their occurrence in Bolivia. Bidens subalternans var. simulans and B. aurea are reported for the first time from Bolivia. Descriptions, distribution maps, identification key, illustrations, and local vernacular names of all taxa are provided.
Advances in the Knowledge and Study of Invasive Alien Species in Bolivia
(2021) Wendy L. Tejeda; Adriana Rico‐Cernohorska; Stephan Beck; Alfredo F. Fuentes; Robert B. Wallace; Guido Miranda; Luís F. Aguirre; María del Pilar Fernández Murillo
The value of knowledge about the negative effects of invasive alien species (IAS) on biodiversity, ecosystems, national economies, human health, and climate change mitigation is increasingly important. Bolivia considered the problem of IAS in the Biological Invasions, Invasive Information Network I3N–IABIN workshop, which generated an IAS database for different countries detailing the location of species, their economic and ecological impacts, as well as entry routes, and propagation, although for the most part, only lists of plant and animal IAS can be derived from national scientific collections. Here, we feature several plant and animal species with more detailed information. Finally, due to the consequences of IAS on the country's native biodiversity, human health, and economic activities these systematization initiatives informed national policy. In Bolivia, there are at least 150 species considered as introduced or exotic, including crop species, information that needs to be refined and updated.
Agrobiodiversity as a Reservoir of Medicinal Resources: Ethnobotanical Insights from Aymara Communities in the Bolivian Andean Altiplano
(Multidisciplinary Digital Publishing Institute, 2025) Simón Cocarico; Diego Rivera; Stephan Beck; Concepción Obón
This study investigates the medicinal potential of cultivated plants and weeds in Aymara communities around Lake Titicaca. It highlights the intricate connection between horticultural diversity and traditional healing practices. Through ethnobotanical research involving 228 informants across multiple locations in Bolivia, we documented 239 medicinal plant species, focusing on the diversity within cultivated landscapes. Among these, 56 species are cultivated crops, 17 are agricultural weeds, and 19 species have dual status, serving as both wild and cultivated plants depending on environmental conditions. Women are repositories of knowledge for 81% (193) of total medicinal plant species, while men know 47% (113) of species. Women display dominant knowledge of cultivated species (89%, or 50 species) and purchase medicinal plants from local markets; women know 92% (24 species) vs. men’s 15% (4 species). Our results suggest men may use a smaller set of species more frequently, while women know and use a broader range of species. The analysis of plant life forms revealed the significant medicinal roles of perennials, annuals, subshrubs, and shrubs, which together account for over 67% of the documented species and 73% of the use reports. Arboreal species are present but have a comparatively smaller role in traditional medicine. In total, we recorded 1477 use reports addressing 260 pathologies across 28 major health categories. Notably, cultivated plants and weeds represent 38.8% of the medicinal species, highlighting their essential role in local healthcare practices. By assessing the contributions of native and introduced species, this study sheds light on the complex botanical resources integrated into Aymara agricultural systems. These findings deepen our understanding of medicinal plant diversity and underscore the importance of agrobiodiversity as a cornerstone of community health and cultural resilience in the Andean region. This research also emphasizes the often-overlooked medicinal value of cultivated landscapes and agricultural margins.
An integrated assessment of the vascular plant species of the Americas
(American Association for the Advancement of Science, 2017) Carmen Ulloa Ulloa; Pedro Acevedo‐Rodríguez; Stephan Beck; Manuel J. Belgrano; Rodrigo Bernal; Paul E. Berry; Lois Brako; Marcela Celis; Gerrit Davidse; Rafaela Campostrini Forzza
The cataloging of the vascular plants of the Americas has a centuries-long history, but it is only in recent decades that an overview of the entire flora has become possible. We present an integrated assessment of all known native species of vascular plants in the Americas. Twelve regional and national checklists, prepared over the past 25 years and including two large ongoing flora projects, were merged into a single list. Our publicly searchable checklist includes 124,993 species, 6227 genera, and 355 families, which correspond to 33% of the 383,671 vascular plant species known worldwide. In the past 25 years, the rate at which new species descriptions are added has averaged 744 annually for the Americas, and we can expect the total to reach about 150,000.
Anti-Leishmanial Lindenane Sesquiterpenes from<i>Hedyosmum angustifolium</i>
(Thieme Medical Publishers (Germany), 2009) Lucia Acebey; Valérie Jullian; Denis Séréno; Séverine Chevalley; Yannick Estevez; Claude Moulis; Stephan Beck; Alexis Valentin; Alberto Giménez; Michel Sauvain
The aim of this work is the isolation of anti-leishmanial compounds from the ethyl acetate extracts of the bark of HEDYOSMUM ANGUSTIFOLIUM. We have successfully isolated and characterized five sesquiterpenes: one new compound (oxyonoseriolide, 1), one compound isolated for the first time from a natural source (hedyosmone, 2), and three known sesquiterpenes (onoseriolide, 3; chloranthalactone A, 4; and spathulenol, 5) that had not been previously isolated from H. ANGUSTIFOLIUM. The biological activities of 1- 5 showed that onoseriolide ( 3) was the most active compound against axenic amastigotes from LEISHMANIA AMAZONENSIS and L. INFANTUM. Moreover, it was still active on the intramacrophagic amastigotes of L. INFANTUM. The isolated compounds have also been tested on PLASMODIUM FALCIPARUM and against various mammalian cell lines.
Balance de investigaciones sobre la reconstitución de la fertilidad del suelo en el Altiplano central Boliviano (TROPANDES - Bolivia)
(Centre National de la Recherche Scientifique, 2006) Dominique Hervé; Stephan Beck
Directeurs de la publication : D. Hervé, S. Beck, R. M. Moraes.
Biodiversity Patterns and Continental Insularity in the Tropical High Andes
(Institute of Arctic and Alpine Research, 2014) Fabien Anthelme; Dean Jacobsen; Petr Macek; Rosa Isela Meneses; Pierre Moret; Stephan Beck; Olivier Dangles
Alpine areas of the tropical Andes constitute the largest of all tropical alpine regions worldwide. They experience a particularly harsh climate, and they are fragmented into tropical alpine islands at various spatial scales. These factors generate unique patterns of continental insularity, whose impacts on biodiversity remain to be examined precisely. By reviewing existing literature and by presenting unpublished data on beta-diversity and endemism for a wide array of taxonomic groups, we aimed at providing a clear, overall picture of the isolation-biodiversity relationship in the tropical alpine environments of the Andes. Our analyses showed that (1) taxa with better dispersal capacities and wider distributions (e.g., grasses and birds) were less restricted to alpine areas at local scale; (2) similarity among communities decreased with spatial distance between isolated alpine areas; and (3) endemism reached a peak in small alpine areas strongly isolated from main alpine islands. These results pinpoint continental insularity as a powerful driver of biodiversity in the tropical High Andes. A combination of human activities and warming is expected to increase the effects of continental insularity in the next decades, especially by amplifying the resistance of the lowland matrix that surrounds tropical alpine islands.
Bolivianine, a New Sesterpene with an Unusual Skeleton from <i>Hedyosmum angustifolium,</i> and Its Isomer, Isobolivianine
(American Chemical Society, 2007) Lucia Acebey; Michel Sauvain; Stephan Beck; Claude Moulis; Aberto Gimenez; Valérie Jullian
Bolivianine, a novel sesterpene with an unprecedented skeleton, has been isolated from the trunk bark of Hedyosmum angustifolium (Chloranthaceae), with isobolivianine, an isomer formed under acidic conditions. The structure and relative stereochemistry were elucidated on the basis of spectroscopic data. A hypothesis for biogenesis was made.
Chromosome numbers and karyotypes of South American species and populations of Hypochaeris (Asteraceae)
(Oxford University Press, 2007) Hanna Weiss‐Schneeweiss; Tod F. Stuessy; Karin Tremetsberger; Estrella Urtubey; Hugo Valdebenito; Stephan Beck; Carlos M. Baeza
One hundred and thirty-seven new chromosome counts are reported from 104 populations of 26 native South American taxa of Hypochaeris (Asteraceae, Lactuceae), together with two invasive Mediterranean species: H. glabra and H. radicata. First reports are provided for seven taxa (H. alba, H. cf. eremophila, H. caespitosa, H. hookeri, H. parodii, H. patagonica and H. pinnatifida) and one new ploidy level is reported (diploid for H. incana, so far known only as a tetraploid). Including the results of this study, the chromosomes of 39 of the c. 50 Hypochaeris species known from the New World have now been counted. Most species are diploid with 2n = 2x = 8 and have bimodal, asymmetrical karyotypes. Tetraploidy (2n = 4x = 16) is reported here for the first time in H. caespitosa. Infra-specific polyploidy (probably autopolyploidy) is reported in H. incana and H. taraxacoides, both cases including infra-populational cytotype mixtures (2x and 4x). Polyploidy is now known from eight South American Hypochaeris species (c. 16%). Basic karyotype analyses allow the placement of the newly counted taxa into previously proposed but slightly modified groupings and provide the framework for further molecular cytogenetic analyses. The reported findings suggest that chromosomal change in South American Hypochaeris, in contrast to Old World species, has not involved aneuploidy, but polyploidy and/or more subtle changes in chromosome length, perhaps via satellite DNA amplification/deletion or activity of retroelements, and rDNA reorganization.
Decomposition of plant litter and roots in a long fallow system (Bolivian Altiplano)
(2006) Marie‐Madeleine Coûteaux; Dominique Hervé; Stephan Beck
Descomposición de hojarasca y raíces en un sistema de descanso largo (Altiplano de Bolivia)
(2006) Marie‐Madeleine Coûteaux; Dominique Hervé; Stephan Beck
The fallow agriculture system is based on the fact that after depletion of soil organic matter due to cultivation, the soil can recover its initial level of fertility by leaving the fields for a long fallow period. During this period, the soil organic matter stock will be reconstituted by the inputs of the residues of the natural vegetation succession. The decomposition of 12 kinds of plant material (different organs and species) from a young three-years old and an old eight-years old fallow was studied in the semiarid Bolivian puna (Patacamaya, South of La Paz, 3,800 m asl.) by incubating litterbags over one or two years in field conditions. A PCA ordinated the initial litter quality in three groups: (i) the grass shoots, (ii) the leaves and stems of non-grass plants, and (iii) the roots.
Dinámica sucesional de la vegetación en un sistema agrícola con descanso largo en el Altiplano central boliviano
(2006) Teresa Ortuño; Stephan Beck; Lina Sarmiento
Diversidad arbórea del bosque tucumano-boliviano en la alta cuenca del río Bermejo (Tarija, Bolivia)
(2019) Silvia C. Gallegos; Freddy S. Zenteno-Ruíz; Stephan Beck; Ramiro Pablo López
Effects of disturbance and altitude on soil seed banks of tropical montane forests
(Cambridge University Press, 2013) Denis Lippok; Florian Walter; Isabell Hensen; Stephan Beck; Matthias Schleuning
Abstract: Vast areas of tropical forests have been deforested by human activities, resulting in landscapes comprising forest fragments in matrices of deforested habitats. Soil seed banks (SSB) are essential sources for the regeneration of tropical forests after disturbance. In a fragmented montane landscape in the Bolivian Andes, we investigated SSB in three different habitat types that were associated with different degrees of disturbance, i.e. in forest interior, at forest edges and in deforested habitats. Sampling of habitats was replicated at six sites ranging in altitude from 1950 to 2450 m asl. We extracted seeds from dried soil samples by sieving, classified seeds into morphospecies and size classes, and characterized SSB in terms of density, species richness and composition. We tested effects of disturbance (i.e. habitat type) and altitude on SSB characteristics. Overall, small seeds (<1 mm) dominated SSB (81% of sampled seeds). Seed density and species richness were lowest in deforested habitats, especially in large seeds and distant from adjacent forests (≥20 m), while small-seeded species were most numerous near forest margins. Species turnover between habitats was high. Altitude altered the composition of SSB, but had no effects on seed density and species richness. We conclude that the potential of SSB for natural regeneration of deforested habitats is low and decreases with increasing distance from forest remnants and that forest edges may be eventually invaded by small-seeded species from deforested habitats.
Evidence of moist niches in the Bolivian Andes during the mid-Holocene arid period
(SAGE Publishing, 2013) Marie‐Pierre Ledru; Vincent Jomelli; Laurent Brémond; Teresa Ortuño; Pablo Cruz; Ilham Bentaleb; Florence Sylvestre; Adèle Kuentz; Stephan Beck; Céline Martin
To examine the climate of the mid-Holocene and early human settings in the Andes when the Altiplano was recording the most arid phase of the Holocene, we analyzed plant-related proxies (pollen, phytoliths, diatoms, stable isotopes) from a sediment core sampled at high elevation in the Eastern Cordillera of Bolivia. Our study was carried out in the wetland of Tiquimani (16°12′06.8″S; 68°3′51.5″W; 3760 m), on a well-known pathway between Amazonia and Altiplano. The 7000-year old record shows a two-step mid-Holocene with a dry climate between 6800 and 5800, followed by a wetter period that lasted until 3200 cal. yr BP. In the Central Andes of Bolivia, a widespread aridity was observed on the Altiplano during the mid-Holocene. However, here, we show that moisture was maintained locally by convective activity from the Amazon lowlands. During the arid interval between 5000 and 4000 yr BP, these niches of moisture produced specific grasslands that may have enabled the survival of an archaic culture of hunter–gatherers on the Puna. This development occurred 2000 years before expansion of quinoa cultivation on the Puna.
Factors limiting montane forest regeneration in bracken-dominated habitats in the tropics
(Elsevier BV, 2016) Silvia C. Gallegos; Stephan Beck; Isabell Hensen; Francisco Saavedra; Denis Lippok; Matthias Schleuning
Flora of Bolivia - where do we stand?
(Rio de Janeiro Botanical Garden Research Institute, 2015) Rosa Isela Meneses; Stephan Beck; E. García; M. Mercado; A. Araujo; Monica G. Serrano
Abstract The botanical exploration of Bolivia during the last two centuries did not leave a botanical legacy in the country. Only towards the end of the 20th century Bolivia saw the start of the biology careers at its universities and the development of its own herbaria. Nowadays there are important herbaria in La Paz, Santa Cruz, Cochabamba and Sucre with collections ranging between 40,000 and 350,000 specimens. In 2014 a catalogue of the vascular flora of Bolivia was published under the auspices of the Missouri Botanical Garden, recording 15,345 species, of which 12,165 are native and 2,343 are endemic, while 694 are cultivated, 267 adventitious and 221 are naturalized. Endemic species of vascular plants add up to 2,343 species. The 286 families listed follow the APG III classification system. There are about 150 botanists in Bolivia interested in studying the country's rich flora. During a workshop organized in 2013 to promote a Flora of Bolivia, the participants established jointly a preliminary format for the taxonomic treatments. The Flora of Bolivia is planned to be an electronic, open access publication with international participation. The World Flora represents a challenge that must be tackled by circumscribing, verifying and recording all species known within our territory, and it is expected that it will have positive repercussions from and towards the ongoing Flora of Bolivia, in a similar way as the long running series of the Flora Neotropica has provided a wider picture that can be adapted and modified to fit our particular country.
Floristic inventory of Bolivia — An indispensable contribution to sustainable development
(Taylor & Francis, 2001) Stephan Beck
Forest recovery of areas deforested by fire increases with elevation in the tropical Andes
(Elsevier BV, 2013) Denis Lippok; Stephan Beck; Daniel Renison; Silvia C. Gallegos; Francisco Saavedra; Isabell Hensen; Matthias Schleuning