Irene Carolina Fedon | Universidad Central de Venezuela (original) (raw)

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Papers by Irene Carolina Fedon

Research paper thumbnail of Liliopsida, Cyperaceae, Cephalocarpus confertus Gilly, Guyana Shield, Brazil, Colombia and Venezuela

Check List, 2011

The genus Cephalocarpus (Cyperaceae), of South American distribution is represented by four speci... more The genus Cephalocarpus (Cyperaceae), of South American distribution is represented by four species. The present work extends the distribution of Cephalocarpus cofertus Gilly based on analysis of samples from the Missouri Botanical Garden Herbarium, literature and online databases. As a result this species is reported for Brazil, Colombia and Venezuela and is removed from the endemic status for Venezuela.

Research paper thumbnail of Patrones espaciales en un herbazal halófilo: suelos, comunidades vegetales y plasticidad fenotípica de Sporobolus virginicus (L.) Kunth, Révis. Gramin (1829) en el Estado Miranda, Venezuela

Biota Colombiana, 2018

Avendaño et al. Patrones espaciales en un herbazal halófilo: suelos, comunidades vegetales y plas... more Avendaño et al. Patrones espaciales en un herbazal halófilo: suelos, comunidades vegetales y plasticidad fenotípica de Sporobolus virginicus (L.) Kunth, Révis. Gramin. 1: 67 (1829) en el Estado Miranda, Venezuela Resumen Se estudió la asociación entre los cambios del sustrato y la vegetación en un herbazal halófilo dominado por Sporobolus virginicus. Se cuantificaron la densidad aparente (g/cm³), la materia orgánica (%), el carbono inorgánico (%), el pH, la textura, la salinidad del suelo (‰) y la salinidad intersticial (‰), así como la cobertura relativa de cada especie (%), la cobertura total (%) y la biomasa total (g/m²) de la vegetación, en 42 unidades de muestreo ubicadas en un transecto de 66 metros de longitud. La comunidad conformada por 7 especies, estuvo dominada por 2 morfotipos de S. virginicus. El morfotipo grande (probablemente variedad virginicus) estuvo asociado con suelos de mayor pH, mayor densidad aparente, menor salinidad y menor porcentaje de materia orgánica, en comparación con el morfotipo pequeño (probablemente variedad minor). El pH, el porcentaje de materia orgánica, la salinidad y la densidad aparente determinaron significativamente (p<0,001) 26 % de la variación explicada en la comunidad. Sobre el transecto se conformaron 3 zonas con características edáficas distintas, en las cuales se establecieron distintas comunidades herbáceas con algunas especies compartidas. La dinámica del agua en el suelo podría responder a pequeñas variaciones en la microtopografía, lo que determinaría diferencias en los procesos de inundación y evaporación a escala local. Palabras clave. Estado Miranda. Herbáceas halófilas. Humedales. Suelos hídricos.

Research paper thumbnail of Spatial patterns in a halophyte grassland: soils, plant communities and phenotypic plasticity of Sporobolus virginicus (L.) Kunth, Révis. Gramin. 1: 67 (1829) in Miranda state, Venezuela

Biota Colombiana, 2018

The relationship between soil and vegetation was studied in a salt marsh dominated by Sporobolus ... more The relationship between soil and vegetation was studied in a salt marsh dominated by Sporobolus virginicus (L.) Kunth (Poaceae). We used 42 sampling units placed on a 66 m long transect; in each soil sample we measured the bulk density (g/cm³), organic matter (%), inorganic carbon (%), pH, texture, soil salinity (‰) and interstitial salinity (‰). Also, the relative cover of each species (%), total vegetation cover (%), total biomass of the vegetation (g/m²), and the relative composition (%) of each species was measured. The community consisted of 7 species and was dominated by 2 S. virginicus morphotypes: a large morphotype (probably virginicus variety) was associated with soils characterized by higher pH, higher bulk density, lower salinity and lower organic matter (%), in comparison with the small morphotype (probably minor L. M. Bailey variety). The pH, organic matter, salinity and bulk density determined significantly (p&lt;0.001) 26% of explained variance of this community. The transect showed three zones with different edaphic characteristics and different herbaceous communities; nevertheless, those communities had some common species. The water dynamic of the soil may respond to small topographic variations, which could in turn determine differences on local flood and evaporation processes.

Research paper thumbnail of El género Cyperus l. (Cyperaceae, Liliopsidae) en el Herbario Nacional de Venezuela (VEN)

The grasses of the genus Cyperus L. are mostly cosmopolitan overgrowths. The objectives were to q... more The grasses of the genus Cyperus L. are mostly cosmopolitan overgrowths. The objectives were to quantify the number of species of Cyperus deposited in VEN, exsiccata number and geographical distribution for species in Venezuela, also to compare it with 15 Venezuelan herbaria; for she/he was carried out it the revision of the herbarium VEN, throwing 1340 exsiccatas corresponding to 57 species, representing 31% of the total of exsiccata of the genus Cyperus deposited in 16 Venezuelan herbaria and 87% of the species reported for the country. VEN bill with the biggest exsiccata collection and species inside the genus. It is important the study of collections deposited in different herbaria to carry out botanical listings in Venezuela, allowing to establish the holes of information product of the sampling lack. Las hierbas del género Cyperus L. son mayormente malezas cosmopolitas. Los objetivos fueron cuantificar el número de especies de Cyperus depositados en VEN, número de exsiccata y ...

Research paper thumbnail of RHYNCHOSPORA GIGANTEA LINK (CYPERACEAE), NUEVO REGISTRO PARA EL ESTADO SUCRE Y NOTAS SOBRE SU HÁBITAT / Rhynchospora gigantea Link (Cyperaceae), new record for Sucre State and notes on its habitat

Research paper thumbnail of ANGIOSPERMAS TREPADORAS DE LOS BOSQUES RIBEREÑOS DE UNA SECCIÓN DE LA CUENCA BAJA DE LOS RÍOS CUAO-SIPAPO (ESTADO AMAZONAS, VENEZUELA) Climbing angiosperms of the riparian forest of a section of the lower basin of the rivers Cuao-Sipapo (Amazonas State, Venezuela)

A list of the species of climbers growing in the riparian forests of the Cuao-Sipapo- Orinoco Mid... more A list of the species of climbers growing in the riparian forests of the Cuao-Sipapo- Orinoco Middle rivers was elaborated. The study site is located in the area of confluence of the three mentioned rivers, in Municipio Autana, Amazonas State (4°54' and 5°3' Lat. N, 67°34' and 67°46' Long. W, approx. 100-250 m asl); has a seasonal climate and dom- inated by evergreen macrothermics lowland, seasonally flooded forests. In addition to the checklist a summary table is presented with the total number of families, genera and species, where the dominant families were highlighted. A total of 109 species of climbing plants were found, these belonging to 28 families and 68 genera; Bignoniaceae, Fabaceae, 7

Research paper thumbnail of Angiospermas trepadoras de los bosques ribereños de una sección de la cuenca baja de los ríos Cuao-Sipapo (Estado Amazonas, Venezuela)

Acta Botánica …, 2005

Angiospermas trepadoras de los bosques ribereños de unasección de lacuencabaja de los ríos cuaosi... more Angiospermas trepadoras de los bosques ribereños de unasección de lacuencabaja de los ríos cuaosipapo (estado amazonas, venezuela)

Research paper thumbnail of Amphibia, Anura, Hylidae, Scarthyla vigilans: range extensions and new state records from Delta Amacuro and Miranda states, Venezuela

Research paper thumbnail of Climbing angiosperms of the riparian forest of a section of the lower basin of the rivers Cuao-Sipapo (Amazonas State, Venezuela)

Acta Botanica Venezuelica, 2005

Research paper thumbnail of Fuirena Robusta Kunth (Cyperaceae): New record for Venezuela

Acta Botanica Venezuelica, 2004

Research paper thumbnail of ANGIOSPERMAS TREPADORAS DE LOS BOSQUES RIBEREÑOS DE UNA SECCIÓN DE LA CUENCA BAJA DE LOS RÍOS CUAO-SIPAPO (ESTADO AMAZONAS, VENEZUELA) Climbing angiosperms of the riparian forest of a section of the lower basin of the rivers Cuao-Sipapo (Amazonas State, Venezuela)

Research paper thumbnail of Rhynchospora Gigantea Link (Cyperaceae), New record for Sucre State and notes on its Habitat

Acta Botanica Venezuelica, 2004

Research paper thumbnail of Fuirena Robusta Kunth (Cyperaceae): Nuevo Registro Para Venezuela

Acta Botanica Venezuelica, 2004

Research paper thumbnail of Bulbostylis medusae (Cyperaceae), a New Species from Venezuela

Novon, 2007

Bulbostylis medusae Prata, Reynders & Goetghebeur from Venezuela is fully described and illustrat... more Bulbostylis medusae Prata, Reynders & Goetghebeur from Venezuela is fully described and illustrated. This species differs from all other South American Bulbostylis Kunth species by the combination of long-ciliated leaf sheaths, leaf apices, bracts, and spikelet axes. The new species resembles B. sellowiana (Kunth) Palla, and a comparison of the two species is made.

Research paper thumbnail of Liliopsida, Cyperaceae, Cephalocarpus confertus Gilly, Guyana Shield, Brazil, Colombia and Venezuela

Check List, 2011

The genus Cephalocarpus (Cyperaceae), of South American distribution is represented by four speci... more The genus Cephalocarpus (Cyperaceae), of South American distribution is represented by four species. The present work extends the distribution of Cephalocarpus cofertus Gilly based on analysis of samples from the Missouri Botanical Garden Herbarium, literature and online databases. As a result this species is reported for Brazil, Colombia and Venezuela and is removed from the endemic status for Venezuela.

Research paper thumbnail of Patrones espaciales en un herbazal halófilo: suelos, comunidades vegetales y plasticidad fenotípica de Sporobolus virginicus (L.) Kunth, Révis. Gramin (1829) en el Estado Miranda, Venezuela

Biota Colombiana, 2018

Avendaño et al. Patrones espaciales en un herbazal halófilo: suelos, comunidades vegetales y plas... more Avendaño et al. Patrones espaciales en un herbazal halófilo: suelos, comunidades vegetales y plasticidad fenotípica de Sporobolus virginicus (L.) Kunth, Révis. Gramin. 1: 67 (1829) en el Estado Miranda, Venezuela Resumen Se estudió la asociación entre los cambios del sustrato y la vegetación en un herbazal halófilo dominado por Sporobolus virginicus. Se cuantificaron la densidad aparente (g/cm³), la materia orgánica (%), el carbono inorgánico (%), el pH, la textura, la salinidad del suelo (‰) y la salinidad intersticial (‰), así como la cobertura relativa de cada especie (%), la cobertura total (%) y la biomasa total (g/m²) de la vegetación, en 42 unidades de muestreo ubicadas en un transecto de 66 metros de longitud. La comunidad conformada por 7 especies, estuvo dominada por 2 morfotipos de S. virginicus. El morfotipo grande (probablemente variedad virginicus) estuvo asociado con suelos de mayor pH, mayor densidad aparente, menor salinidad y menor porcentaje de materia orgánica, en comparación con el morfotipo pequeño (probablemente variedad minor). El pH, el porcentaje de materia orgánica, la salinidad y la densidad aparente determinaron significativamente (p<0,001) 26 % de la variación explicada en la comunidad. Sobre el transecto se conformaron 3 zonas con características edáficas distintas, en las cuales se establecieron distintas comunidades herbáceas con algunas especies compartidas. La dinámica del agua en el suelo podría responder a pequeñas variaciones en la microtopografía, lo que determinaría diferencias en los procesos de inundación y evaporación a escala local. Palabras clave. Estado Miranda. Herbáceas halófilas. Humedales. Suelos hídricos.

Research paper thumbnail of Spatial patterns in a halophyte grassland: soils, plant communities and phenotypic plasticity of Sporobolus virginicus (L.) Kunth, Révis. Gramin. 1: 67 (1829) in Miranda state, Venezuela

Biota Colombiana, 2018

The relationship between soil and vegetation was studied in a salt marsh dominated by Sporobolus ... more The relationship between soil and vegetation was studied in a salt marsh dominated by Sporobolus virginicus (L.) Kunth (Poaceae). We used 42 sampling units placed on a 66 m long transect; in each soil sample we measured the bulk density (g/cm³), organic matter (%), inorganic carbon (%), pH, texture, soil salinity (‰) and interstitial salinity (‰). Also, the relative cover of each species (%), total vegetation cover (%), total biomass of the vegetation (g/m²), and the relative composition (%) of each species was measured. The community consisted of 7 species and was dominated by 2 S. virginicus morphotypes: a large morphotype (probably virginicus variety) was associated with soils characterized by higher pH, higher bulk density, lower salinity and lower organic matter (%), in comparison with the small morphotype (probably minor L. M. Bailey variety). The pH, organic matter, salinity and bulk density determined significantly (p&lt;0.001) 26% of explained variance of this community. The transect showed three zones with different edaphic characteristics and different herbaceous communities; nevertheless, those communities had some common species. The water dynamic of the soil may respond to small topographic variations, which could in turn determine differences on local flood and evaporation processes.

Research paper thumbnail of El género Cyperus l. (Cyperaceae, Liliopsidae) en el Herbario Nacional de Venezuela (VEN)

The grasses of the genus Cyperus L. are mostly cosmopolitan overgrowths. The objectives were to q... more The grasses of the genus Cyperus L. are mostly cosmopolitan overgrowths. The objectives were to quantify the number of species of Cyperus deposited in VEN, exsiccata number and geographical distribution for species in Venezuela, also to compare it with 15 Venezuelan herbaria; for she/he was carried out it the revision of the herbarium VEN, throwing 1340 exsiccatas corresponding to 57 species, representing 31% of the total of exsiccata of the genus Cyperus deposited in 16 Venezuelan herbaria and 87% of the species reported for the country. VEN bill with the biggest exsiccata collection and species inside the genus. It is important the study of collections deposited in different herbaria to carry out botanical listings in Venezuela, allowing to establish the holes of information product of the sampling lack. Las hierbas del género Cyperus L. son mayormente malezas cosmopolitas. Los objetivos fueron cuantificar el número de especies de Cyperus depositados en VEN, número de exsiccata y ...

Research paper thumbnail of RHYNCHOSPORA GIGANTEA LINK (CYPERACEAE), NUEVO REGISTRO PARA EL ESTADO SUCRE Y NOTAS SOBRE SU HÁBITAT / Rhynchospora gigantea Link (Cyperaceae), new record for Sucre State and notes on its habitat

Research paper thumbnail of ANGIOSPERMAS TREPADORAS DE LOS BOSQUES RIBEREÑOS DE UNA SECCIÓN DE LA CUENCA BAJA DE LOS RÍOS CUAO-SIPAPO (ESTADO AMAZONAS, VENEZUELA) Climbing angiosperms of the riparian forest of a section of the lower basin of the rivers Cuao-Sipapo (Amazonas State, Venezuela)

A list of the species of climbers growing in the riparian forests of the Cuao-Sipapo- Orinoco Mid... more A list of the species of climbers growing in the riparian forests of the Cuao-Sipapo- Orinoco Middle rivers was elaborated. The study site is located in the area of confluence of the three mentioned rivers, in Municipio Autana, Amazonas State (4°54' and 5°3' Lat. N, 67°34' and 67°46' Long. W, approx. 100-250 m asl); has a seasonal climate and dom- inated by evergreen macrothermics lowland, seasonally flooded forests. In addition to the checklist a summary table is presented with the total number of families, genera and species, where the dominant families were highlighted. A total of 109 species of climbing plants were found, these belonging to 28 families and 68 genera; Bignoniaceae, Fabaceae, 7

Research paper thumbnail of Angiospermas trepadoras de los bosques ribereños de una sección de la cuenca baja de los ríos Cuao-Sipapo (Estado Amazonas, Venezuela)

Acta Botánica …, 2005

Angiospermas trepadoras de los bosques ribereños de unasección de lacuencabaja de los ríos cuaosi... more Angiospermas trepadoras de los bosques ribereños de unasección de lacuencabaja de los ríos cuaosipapo (estado amazonas, venezuela)

Research paper thumbnail of Amphibia, Anura, Hylidae, Scarthyla vigilans: range extensions and new state records from Delta Amacuro and Miranda states, Venezuela

Research paper thumbnail of Climbing angiosperms of the riparian forest of a section of the lower basin of the rivers Cuao-Sipapo (Amazonas State, Venezuela)

Acta Botanica Venezuelica, 2005

Research paper thumbnail of Fuirena Robusta Kunth (Cyperaceae): New record for Venezuela

Acta Botanica Venezuelica, 2004

Research paper thumbnail of ANGIOSPERMAS TREPADORAS DE LOS BOSQUES RIBEREÑOS DE UNA SECCIÓN DE LA CUENCA BAJA DE LOS RÍOS CUAO-SIPAPO (ESTADO AMAZONAS, VENEZUELA) Climbing angiosperms of the riparian forest of a section of the lower basin of the rivers Cuao-Sipapo (Amazonas State, Venezuela)

Research paper thumbnail of Rhynchospora Gigantea Link (Cyperaceae), New record for Sucre State and notes on its Habitat

Acta Botanica Venezuelica, 2004

Research paper thumbnail of Fuirena Robusta Kunth (Cyperaceae): Nuevo Registro Para Venezuela

Acta Botanica Venezuelica, 2004

Research paper thumbnail of Bulbostylis medusae (Cyperaceae), a New Species from Venezuela

Novon, 2007

Bulbostylis medusae Prata, Reynders & Goetghebeur from Venezuela is fully described and illustrat... more Bulbostylis medusae Prata, Reynders & Goetghebeur from Venezuela is fully described and illustrated. This species differs from all other South American Bulbostylis Kunth species by the combination of long-ciliated leaf sheaths, leaf apices, bracts, and spikelet axes. The new species resembles B. sellowiana (Kunth) Palla, and a comparison of the two species is made.