This work deals with taxonomic and paleoecological aspects based on Quaternary fossil leaves from... more This work deals with taxonomic and paleoecological aspects based on Quaternary fossil leaves from Venezuela. It is the fi rst of its kind and therefore represents a novelty. The paleofl ora of the El Anís area, Mérida, presents itself as impressions/compressions of fossil angiosperm leaves, this association being very diverse, abundant, and well preserved, what allowed taxonomic treatment. Twentynine taxa were identifi ed belonging to the following families:
Novedades taxonómicas para la Flora de Venezuela, I. Tres nuevas especies de Lachemilla (Focke) Rydberg (Rosaceae)
Three new sepecies of Lachemilla (Focke) Rydberg (Rosaceae): L. involucrata, L. loki-schmidtii an... more Three new sepecies of Lachemilla (Focke) Rydberg (Rosaceae): L. involucrata, L. loki-schmidtii and L. pelusae; are described, this genera is typical of the high mountains of the neotropics and is widely represented in all of the sociations of the vegetation of the páramo, superpáramo and the upper limit of the cloud forest in Venezuela
Análisis de la vegetación del Parque Metropolitano Albarregas, Mérida, Venezuela
The Parque Metropolitano Albarregas (Pamalba) constitutes a shelter for one of the few remaining ... more The Parque Metropolitano Albarregas (Pamalba) constitutes a shelter for one of the few remaining forests in the urban area of the city of Mérida. Its conservation and management require current, basic information, in order to develop future land zoning plans. Therefore, a vegetation characterization study was carried out. 13 Vegetation units were identified, which comprise 65 % of the park surface; of which the forest represents the major unit (22 %). 67 Species belonging to 39 families were identified; the most common species are Ficus insipida, Erythrina poeppigiana and Musa x paradisiacal. In general, the vegetation units have moderate to low diversity values (H’< 1,9). The park’s vegetation grouping responds to an altitude-humidity gradient, which contrasts with a successional gradient. The vegetation’s location, distribution and characteristics evidence its suitability for the development of future urban green corridors that will enhance environmental conservation, public re...
BOTANIC GARDENS CONSERVATION INTERNATIONAL (BGCI) is a membership organization linking botanic ga... more BOTANIC GARDENS CONSERVATION INTERNATIONAL (BGCI) is a membership organization linking botanic gardens in over 100 countries in a shared commitment to biodiversity conservation, sustainable use and environmental education. BGCI aims to mobilize botanic gardens and work with partners to secure plant diversity for the well-being of people and the planet. BGCI provides the Secretariat for the IUCN/SSC Global Tree Specialist Group. FAUNA & FLORA INTERNATIONAL (FFI), founded in 1903 and the world's oldest international conservation organization, acts to conserve threatened species and ecosystems worldwide, choosing solutions that are sustainable, are based on sound science and take account of 7 Conservation and Research Priorities 8 References 10 GLOBALLY THREATENED AND NEAR THREATENED SPECIES 12 Species evaluated as Data Deficient 42 Species evaluated as Least Concern 44 References 48 ANNEX 1 IUCN Red List Categories and Criteria (Version 3.1) 53
Sinopsis del género Lachemilla (Focke) Rydberg (Rosaceae) para Venezuela
Sinopsis of the genus Lachemilla (Focke) Rydberg (Rosaceae) from Venezuela Lachemilla (Focke) Ryd... more Sinopsis of the genus Lachemilla (Focke) Rydberg (Rosaceae) from Venezuela Lachemilla (Focke) Rydberg is one of the characteristic elements of the paramo and superparamo vegetation, it also occurs in the preparano and even in the edges of the High Andean forest, the genus has around 30 species proper of the mountains of Centro and South America. In Venezuela 18 species
The genus Pitcairnia has been poor studied in the Andes and in spite of the recent efforts in the... more The genus Pitcairnia has been poor studied in the Andes and in spite of the recent efforts in the researchs of the family Bromeliaceae taxonomy and tools aspects still remain to be deciphered to facilitate identification. This study presents the synopsis of the genus Pitcairnia for Mérida State (Venezuela) including detailed description of eight species examined, blooming and ecological dates, as well as a key for the determination of the species present in Mérida. One half of the species has some type of endemism, two species are endemic to the Andean region and two are endemic to the State.
A.C. (2012). Evaluación del estado de conservación de los bosques montanos en los Andes tropicale... more A.C. (2012). Evaluación del estado de conservación de los bosques montanos en los Andes tropicales. Ecosistemas 21(1-2):148-166. Los Andes tropicales constituyen una región única con una alta diversidad de hábitats, producto de complejos gradientes espaciales y ambientales. Los bosques montanos de esta región son considerados como una prioridad global de conservación, debido principalmente a su elevada riqueza biológica y de endemismos. Sin embargo su biodiversidad es de las menos conocidas de toda la región tropical, aunque se reconoce la amplia gama de servicios ambientales que prestan, incluyendo la regulación del clima regional y la captura y almacenamiento de carbono. Este artículo ofrece una perspectiva general del estado de conservación de los bosques montanos tropicales andinos y de los retos que esta implica. Asimismo, proporciona información sobre sus amenazas, identificando aquéllas que con mayor probabilidad sean responsables de aumentar el riesgo de extinción de especies. Se resalta la necesidad de disponer de más información sobre el estado de conservación de las especies para identificar las futuras prioridades de conservación en la región. La reciente iniciativa de la "Lista Roja y planeación para la conservación de especies de árboles montanos de los Andes Tropicales", formada por delegados de varios países de la región, constituirá una sólida base para el desarrollo y enfoque de políticas y respuestas de manejo dirigidas a la reducción de la deforestación y pérdida de especies en estos bosques, incluyendo acciones para promover la creación de áreas protegidas, restauración forestal y manejo forestal sostenible.
En la Sierra Nevada de Mérida, entre los 3.000 - 4.000 m snm, crecen tres especies de Miconia (Me... more En la Sierra Nevada de Mérida, entre los 3.000 - 4.000 m snm, crecen tres especies de Miconia (Melastomataceae): M. chionophylla, M. latifolia y M. tinifolia. La primera es un arbusto enano de los bosques de Polylepis sericea y las dos últimas son árboles del bosque paramero. ...
mediante un inventario de plantas vasculares en los alrededores de la ciudad. Se consideró a los ... more mediante un inventario de plantas vasculares en los alrededores de la ciudad. Se consideró a los individuos con DAP > 1 cm, las trepadoras y epifitas encontradas a menos de 5 m de altura, adicionalmente se realizó un inventario completo de plantas vasculares en las principales plazas y parques de la ciudad. Se encontraron 391 especies distribuidas en 291 géneros y pertenecientes a 110 familias. Las familias con mayor número de especies fueron Asteraceae (21), Melastomataceae y Bromeliaceae (16 cada una), Euphorbiaceae y Rubiaceae (14 cada una), Orchidaceae (13) y Acanthaceae (12). Se encontraron algunas especies endémicas y, grupos de plantas como orquídeas, aráceas y helechos se encuentran restringidos a los relictos de bosque ubicados al norte de la ciudad. Se reporta por primera vez en Venezuela Morella cerifera (L.) Small.
Changes in morphological and anatomical leaf characteristics of woody plant species along an alti... more Changes in morphological and anatomical leaf characteristics of woody plant species along an altitudinal gradient as well as between a late-successional and mature upper montane rain forest were examined. For leaf size, the Raunkiaer-Webb classification system was applied. The mature-forest transect comprised eight plots of 0.1 ha between 2300 and 3300 m asl, the successional-forest transect, four plots between 2400 and 2750 m asl. The latter comprised structurally heterogeneous vegetation patches. For each plot the proportions of leaf size classes and of the different categories of leaf shape, margin, and apex were calculated. Leaf size and the proportion of drip-tips decreased with increasing elevation. Serrate leaf margins were more prominent at higher elevations. Stomatal density, leaf thickness and related anatomical characteristics did not show significant trends. Differences between the mature and successional forest plots were generally slight. The advanced age of the successional forest probably led to a convergent development of leaf characteristics. Resumen: Se examinaron los cambios morfolo ´gicos y anato ´micos foliares de diferentes especies de plantas len ˜osas tanto a lo largo de una gradiente altitudinal ası ´como tambie ´n comparando un bosque hu ´medo altimontano sucesional tardı ´o con un bosque maduro. Para la clasificacio ´n del taman ˜o foliar se aplico ´el sistema de Raunkiaer-Webb. El bosque maduro comprendio ´ocho parcelas de 0,1 ha distribuidas entre los 2300 y 3300 m snm, mientras que el bosque sucesional incluyo ´cuatro parcelas entre los 2400 y 2750 m snm. El u ´ltimo se compuso de manchas de vegetacio ´n estructuralmente heteroge ´neas. Para cada parcela se calcularon las proporciones de las clases de taman ˜o foliar y de las diferentes categorı ´as de forma, margen y a ´pice foliar. El taman ˜o foliar y la proporcio ´n de hojas con a ´pice gotero decaen con el incremento altitudinal. En altitudes superiores se presenta una mayor abundancia de hojas con margen aserrado. En cuanto se refiere a la densidad de estomas, el grosor foliar y caracterı ´sticas anato ´micas relacionadas, no existen tendencias significativas. Debido a la falta de diferencias obvias entre el bosque maduro y bosque sucesional, se puede suponer que la edad avanzada del bosque sucesional probablemente condujo a un desarrollo convergente de las caracterı ´sticas foliares.
BOTANIC GARDENS CONSERVATION INTERNATIONAL (BGCI) is a membership organization linking botanic ga... more BOTANIC GARDENS CONSERVATION INTERNATIONAL (BGCI) is a membership organization linking botanic gardens in over 100 countries in a shared commitment to biodiversity conservation, sustainable use and environmental education. BGCI aims to mobilize botanic gardens and work with partners to secure plant diversity for the well-being of people and the planet. BGCI provides the Secretariat for the IUCN/SSC Global Tree Specialist Group. FAUNA & FLORA INTERNATIONAL (FFI), founded in 1903 and the world's oldest international conservation organization, acts to conserve threatened species and ecosystems worldwide, choosing solutions that are sustainable, are based on sound science and take account of 7 Conservation and Research Priorities 8 References 10 GLOBALLY THREATENED AND NEAR THREATENED SPECIES 12 Species evaluated as Data Deficient 42 Species evaluated as Least Concern 44 References 48 ANNEX 1 IUCN Red List Categories and Criteria (Version 3.1) 53
Relación entre la morfoanatomía foliar de tres especies de miconia (melastomataceae) con su hábit... more Relación entre la morfoanatomía foliar de tres especies de miconia (melastomataceae) con su hábitat y distribución altitudinal en el parque nacional sierra nevada de Mérida, Venezuela
Leaf anatomy of Oritrophium (H.B.K.) Cuatrec. of the Paramo Sierra Nevada, Loma Redonda Station. ... more Leaf anatomy of Oritrophium (H.B.K.) Cuatrec. of the Paramo Sierra Nevada, Loma Redonda Station. A description of the leaf anatomy of two rosette plants that grow at 4.040 m, Oritrophium paramense and O. Peruvianum is dealt with. The common and differential features that enable them to adapt themselves to the Páramo enviroment where they are submited to conditions of intense
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