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1.
BAG, J. basic appl. genet. (Online) ; 31(2): 27-38, Dec. 2020. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1345378

ABSTRACT

ABSTRACT An analysis was made of the correspondence between species diversity and chromosome number (CN) diversity across 13 Protected Wild Areas (PWA) in the Araucanía Region of southern Chile, encompassing 84 plant species with available cytogenetic data. Our aim was to establish whether higher species diversity within a PWA entails higher CN variation as based on the index of chromosome number heterogeneity (ICNH). The CN data were extracted from databases for Chilean plants, and the ICNH for the flora of each PWA was calculated. Results showed that in nine PWA the species diversity clearly correlates with CN diversity. However, four PWA do not fit this trend. The percentage of species with CN data varied between 9.6% and 24.5% among PWA, with 11 PWA presenting percentages higher than 11%. A 27.3% of the Chilean vascular plant species with available cytogenetic data were studied here for the 13 PWA. The results obtained by studying one part of the flora with available CN data suggest that the PWA could be an important reservoir of genetic diversity at a chromosome level, thus justifying the protective role of the PWA as biodiversity conservation sites.


RESUMEN Se realizó un análisis de la correspondencia entre la diversidad de especies y la diversidad de números cromosómicos (CN) en 13 Áreas Silvestres Protegidas (PWA) en la Región de La Araucanía en el sur de Chile, incluyendo 84 especies de plantas con datos citogenéticos disponibles. El objetivo fue establecer si una mayor diversidad de especies dentro de un PWA implica una mayor diversidad en CN expresado en base al Índice de Heterogeneidad Cromosómica (ICNH). Los CN de cada especie se extrajeron de bases de datos para plantas chilenas y se calculó el ICNH para la flora de cada PWA. Los resultados mostraron que en nueve PWA la diversidad de especies se correlaciona claramente con la diversidad de CN. Sin embargo, cuatro PWA no se ajustan a esta tendencia. El porcentaje de especies con datos de CN varió entre 9,6% y 24,5% entre PWA, con 11 PWA presentando porcentajes superiores al 11%. Un 27,3% de las especies de plantas vasculares chilenas con datos citogenéticos disponibles fueron estudiadas para las 13 PWA. Los resultados obtenidos al estudiar parte de la flora sugieren que las PWA serían un reservorio importante de diversidad genética a nivel cromosómico como se muestra aquí, justificando así el papel protector de las PWA como sitios de conservación de la biodiversidad.

2.
Rev. biol. trop ; 68mar. 2020.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1507620

ABSTRACT

Introducción: La flora de la Isla del Coco ha sido objeto de diversos esfuerzos de recolecta, estudios y publicaciones desde hace más de 300 años, hasta llegar a registrarse 263 especies; no obstante, una exploración reciente permitió determinar que se han presentado muchos cambios nomenclaturales, de clasificación y de incremento de especies desde la última publicación, lo cual hace necesario la publicación de una lista actualizada de especies. Objetivo: Elaborar un catálogo actualizado de las plantas vasculares de la Isla del Coco. Métodos: Mediante la búsqueda y revisión de ejemplares de herbario, publicaciones y recolecta de plantas entre 2016 y 2017, se elaboró una lista actualizada de plantas de la isla. Además, se determinó la riqueza estimada y la calidad del inventario utilizando estimadores de biodiversidad y la proporción de especies de acuerdo a su forma, hábitat epífito y procedencia. Resultados: Se registraron 296 especies de plantas vasculares, en 199 géneros y 82 familias, lo cual representa alrededor de un 80 % de la diversidad esperada según los estimadores utilizados (Chao-1 y ecuación de Clench). Del total, 219 (74%) especies son nativas y 77 (26%) son introducidas. Las especies nativas incluyen angiospermas (53%), helechos (44%) y licófitos (3%) y las introducidas solo angiospermas. Se indican las familias y géneros más diversos y las especies más comunes o abundantes. Se presenta un endemismo del 22% (48 spp.) de la flora nativa, compuesto principalmente por helechos (58%). La flora presenta una alta proporción de especies herbáceas (63%) y una baja representación de especies arborescentes (12%) y de bejucos y enredaderas (8%). También se presenta una alta proporción de epífitas, con un 20% del total de la flora, compuesto mayormente por helechos (69%). Este estudio adicionó 45 nuevas especies a la isla, de las cuales 16 son especies nuevas para la ciencia y endémicas para la isla y ocho son especies introducidas. También se actualizaron o corrigieron 36 nombres de especies en comparación con Trusty et al. (2006). Se proporciona un catálogo de especies con anotaciones. Conclusiones: La flora de la Isla del Coco presenta ciertas particularidades que la distinguen de otras islas oceánicas del Pacífico, en especial por la alta proporción de helechos endémicos y la alta diversidad de este grupo en general y el porcentaje relativamente bajo de endemismo. También es característico la baja diversidad de especies arbóreas, con una alta dominancia de Sacoglottis holdridgei en todos los bosques de la Isla y la alta proporción de especies epífitas, compuesto principalmente por helechos. La proporción de especies introducidas es relativamente baja en comparación con otras islas oceánicas del Pacífico.


Introduction: The flora of Isla del Coco has been the subject of various collection studies and publications efforts for more than 300 years. During these years 263 species were registered; however, there have been nomenclature and classification changes, and an increase of known species since the last publication. Objective: To prepare an updated catalog of the vascular plants of Isla del Coco. Methods: The catalog present here is based on the review of herbarium specimens, publications, and plants collected between 2016 and 2017 by the authors. An updated list of plants on the island was prepared. In addition, the estimated richness and the quality of the inventory were determined through biodiversity estimators and the proportion of species according to their form, epiphytic habitat, and origin. Results: 296 species of vascular plants were registered, corresponding to 199 genera and 82 families, which represents about 80% of the expected diversity according to the estimators used (Chao-1 and Clench equation). Of the total, 219 (74%) species are native and 77 (26%) are introduced. Native species include angiosperms (53%), ferns (44%) and lycophytes (3%), and those introduced are represented only by angiosperms. The most diverse families and genera and the most common or abundant species are indicated. From the native flora, 48 spp. (22%) are endemic, and is mainly composed of ferns (58%). The flora has a high proportion of herbaceous species (63%) and a low representation of arborescent species (12%) and vines (8%). There is also a high proportion of epiphytes (20% of the total flora), mostly composed of ferns (69%). This study added 45 new species records to the island, of which 16 are new species for science and endemic to the island, and eight are introduced species. Thirty-six species names were updated or corrected compared to Trusty et al. (2006). A catalog of species with annotations is provided. Conclusions: The flora of Isla del Coco presents certain peculiarities that distinguish it from other Pacific oceanic islands, especially due to the high proportion of endemic ferns, and the high diversity of this group in general, and the relatively low percentage of endemism. Also, characteristics as the low diversity of tree species, with high dominance of Sacoglottisholdridgei in all the forests of the island, and the high proportion of epiphytic species, mainly composed of ferns. The proportion of introduced species is relatively low, compared to other oceanic Pacific islands.

3.
Article | IMSEAR | ID: sea-188061

ABSTRACT

Studies on the composition and structure of vegetation can provide important information for decision-making and the application of forest-management techniques. The aim of this research was to analyse an area of ​​Caatinga using vegetation characterisation and forest inventory in the Rocha Eterna Community, in the district of São João do Piauí, Brazil. Simple Random Sampling was used, installing 17 sampling units of 20 x 20 m. The phytosociological parameters of the horizontal and vertical structure, the floristic diversity of the species and the timber production in the area were evaluated. Fabaceae was the most representative family. The three most representative species in the area were Senna acuruensis (Benth.) H.S. Irwin & Barneby, Sideroxylon obtusifolium (Roem. & Schult.) T. D. Penn. and Mimosa tenuiflora (Willd.) Poir. The Shannon-Weaver diversity index (H') for the area was 1.74 nats.ind-1. The estimated basal area for the area was 8.68 m².ha-1. The estimated actual volume was 36.56 m³.ha-1. Species diversity in the fragment under study was considered low.

4.
Article | IMSEAR | ID: sea-187850

ABSTRACT

Floristic diversity of the coastal regions of Gulf of Aqaba has been compiled based on the vegetation survey with consultation of literature and herbarium collections during two spring seasons of 2016 and 2017. A total of 109 species belonging to 86 genera in 36 families are recorded in the study area; of which above 50% of the taxa falling in 6 dominant families. Amaranthaceae 23% is the dominant family followed by Poaceae 17%, Fabaceae 7 and 3% Asteraceae. Various vegetation units belonging to three major habitats such as sabkhas, wadis and hilly areas, three life-forms and chorological units have been identified. Based on the physiognomic study the climate of the study area is classified as a transition zone between Mediterranean and sub-Saharan arid zone. A high number of ephemerals in the area indicate dry climate prevailing in these areas. Halophytes dominate along the coastal zone, ephemerals in wadi-bed and chamaephytes in foothills and slopes.

5.
Rev. biol. trop ; 66(1): 227-236, Jan.-Mar. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-897667

ABSTRACT

Resumen Los reportes sobre diversidad de plantas en los bosques tropicales suelen estar restringidos a árboles u otros grupos de plantas leñosas por encima de cierto diámetro del tallo. Sin embargo, otros estudios que incluyen todas las formas de vida sin restricciones de tamaño de los individuos, indican claramente que las plantas no leñosas son igual de importantes. En este estudio se reporta la Riqueza total de especies de plantas vasculares (RTE) en una parcela de una hectárea en un bosque andino del noroccidente de Colombia (6º12'48"N & 75º29'32"O); adicionalmente evaluamos la contribución de los diferentes hábitos de crecimiento a la RTE y el efecto del tamaño de las plantas. Se censaron todos los individuos con diámetro del tronco (D) ≥ 5 cm en 1 ha, y todas las plantas vasculares de todos los tamaños, incluyendo epífitas, en una muestra de 0.25 hectáreas. Se registró un total de 14 545 individuos distribuidos en 318 especies, 72 familias (considerando Pteridophyta como un solo grupo) y 171 géneros. El 99.7 % de las especies son menores de 10 cm de (D) y el 94.4 % son menores a 2.5 cm de (D). Las especies no arbóreas (hierbas terrestres, epífitas y escandentes) representan el 54.3% del total de especies registradas en la parcela, lo que indica que son un componente clave de la estructura, composición y riqueza de este bosque montano neotropical. Estos resultados confirman reportes similares para otros bosques tropicales. Concluimos que para conocer con más detalle la diversidad de florística de un sitio es recomendable: 1) ampliar el rango de tamaño de las plantas considerado comúnmente en los inventarios florísticos y 2) incluir las especies no leñosas; esta información es crucial para tomar mejores decisiones en los esfuerzos de conservación a escala local y global.


Abstract Studies of plant diversity in tropical forests are usually restricted to trees or other groups of woody plants above a certain stem diameter. However, surveys that include all forms of live plants with no restrictions on their sizes, clearly indicate that non-woody plants are equally important. In this study, we reported the total species richness of vascular plants species (TSR) in one hectare plot in an Andean forest in Northwestern Colombia (6º12'48"N & 75º29 32"W). We evaluated the relative contribution of the different growth habits and the effect of the plant size, to TSR. We measured all individuals with diameter (D) ≥ 5 cm in the hectare and all the vascular plants of all sizes, including epiphytes, in a subsample of 0.25 ha. A total of 14 545 individuals distributed in 318 species, 72 families (considering Pteridophyta as one group) and 171 genera were registered. Most of the species showed a (D) < 10 cm (99.7 %) and < 2.5 cm (94.4 %). The no-arboreal species (ground herbs, epiphytes and vines) represented 54.3 % of the total species reported in the plot, indicating that they are important in the structure, composition and species richness of this montane forest. Our results coincide with similar studies in other tropical forests. We concluded that to get a more detailed knowledge of the floristic diversity of a site, it is advisable to: 1) amplify the size range of the plants generally considered in the floristic inventories and 2) to include non-woody species. This information is crucial for making better decisions in local and global conservation efforts. Rev. Biol. Trop. 66(1): 227-236. Epub 2018 March 01.

6.
J Environ Biol ; 2012 Jul; 33(4): 791-797
Article in English | IMSEAR | ID: sea-148430

ABSTRACT

The research was focused on exploring the structure, diversity and form of regeneration process of the Dipterocarp forests in Western Ghats in relation to environmental factors. Eight populations in the distribution range of Dipterocarp forests were selected. In each population 32 plots of 2m?m were laid down randomly. A total of 1243 seedlings < 10 cm dbh (diameter at breast height) belonging to 99 species and 48 families were recorded. The number of regenerated tree species was found to be high in the populations of Mudigere (40), Sakleshpura (40) and Makuta (39), which are characterized by favorable locality factors and lower disturbances. The highest similarity index in species composition was recorded between the populations of Sampaje in Kodagu district and Gundya in Dakshina Kannada (60%) whereas the lowest similarity index was observed between the population of Sringeri in Chikmagalore and Sampaje (53%) and Gundya and Makuta (35%) in Kodagu district. Dipterocarpus indicus was found to be dominant among the regenerated tree species in all the sites studied except Gundy and Sampaje. The frequencies of regeneration classes (seedlings, saplings, poles and adult trees) were shaped as inverse J curve indicating the normal regeneration pattern under the present disturbance. The average disturbance of litter collection, grazing, fire, weeds and canopy opening were significant among different populations (p<0.05). Negative correlation was observed between disturbance and species richness, number of individuals and density.

7.
J Environ Biol ; 2011 Nov; 32(6): 801-806
Article in English | IMSEAR | ID: sea-146650

ABSTRACT

Ailanthus altissima is an invasive species for the native flora of Greece and it could pose a serious threat to the biodiversity and the functioning of ecosystems. The purpose of this study was to investigate the spreading of Ailanthus altissima in urban and non urban areas of North and Central Greece and also to evaluate the effects of its spreading on species composition and floristic diversity in natural ecosystems. The spreading of Ailanthus altissima in urban areas is very intense, mainly in abandoned places (35.29%). It is commonly found in non urban areas of Greece, especially in hedgerows of arable lands (36%) and adjacent wetlands (17%). It is less common in forests (4%), shrublands (11%) and grasslands (9%). The spread of Ailanthus altissima in urban and natural ecosystems is relatively recent. Although it has been recorded at altitudes of up to 640 m, it usually appears at low altitudes of up to 200 m. Floristic diversity was found to be higher in the stands that it dominated (H´=1.574, H´=1.890) in comparison to stands that were dominated by Quercus pubescens (H´=1.468) or Q. coccifera (H´=1.716). This may be contributed to the fact that in those stands synanthropic species, which are usually found in regions of intense human activity, were present together with typical forest vegetation species.

8.
Acta biol. colomb ; 12(supl.1): 75-90, dic. 2007.
Article in Spanish | LILACS | ID: lil-634861

ABSTRACT

Entre junio y agosto de 2005 se determinó la composición florística de las plantas ≥1 cm de DAP en un área de 0,2 ha de bosque húmedo tropical en los corregimientos de Pie de Pató (05º 30' 56" N y 76º 58' 26" W) y Nauca (5º 41' 6" N y 77º 00' 36" W), Alto Baudó, Chocó Colombia. En cada sitio se muestreó un área de 0,1 ha, la cual se dividió en diez transecto de 2 x 50 m cada uno. Se registraron 1.618 individuos, representados en 257 especies, 156 géneros y 56 familias botánicas de los cuales 842 individuos, 161 especies, 108 géneros y 46 familias fueron encontrados en Pie de Pató, y 776 individuos, 161 especies, 98 géneros y 45 familias en Nauca. En Pie de Pató las familias mejor representadas en lo que se refiere a géneros y especies fueron: Rubiaceae (doce géneros y 27 especies), Arecaceae (ocho géneros y ocho especies) y Bombacaceae (siete géneros y diez especies). En Nauca fueron Rubiaceae (once géneros y 25 especies), Moraceae (ocho géneros y trece especies) y Arecaceae (ocho géneros y ocho especies). El índice de riqueza arrojó valores de 23,75 y 24,05 para Pie de Pató y Nauca, en cambio la diversidad fue de 4,43 para ambos sitios. Los resultados indican que los bosques del Alto Baudó son muy diversos y de gran importancia para estudios de la diversidad florística, debido a su ubicación estratégica en el departamento del Chocó.


Between June and August of 2005 the floristic composition ≥1 cm of DAP was determined in an area of ? 0.2 ha of humid tropical forest at the localities of Pie de >Pató (05º 30' 56" N and 76º 58' 26" W) and Nauca (5º 41' 6" N and 77º 00' 36" W), Alto Baudó, Chocó Colombia . En each locality an area of 0.1 ha was sampled which was divided into smaller areas of 2 x 50 cm each. A total of 1618 inidivduals were recorded represented by 257 species, 156 genres and 56 botanical families from which 842 individuals, 161 species, 108 genres and 46 families where found at Pie de Pató, and 776 individuals, 161 species, 98 genres and 45 families at Nauca. At Pie de Pató the families best represented in terms of genres were Rubiaceae (12 genres and 27 species), Arecaceae (eight genres and eight species) and Bombacaceae (seven genres and ten species). At Nauca they were Rubiaceae (eleven genres and 25 species), Moraceae (eight genera and 13 species) and Arecaceae (eigth genres and eight species). The richness index was of 23,75 and 24,05 for Pie de Pató and Nauca respectively. Diversity change was stimated as 4,43 for both localities. These results indicate high diversity of these forests at Alto Baudó.

9.
Rev. peru. biol. (Impr.) ; 12(2)ago. 2005.
Article in Spanish | LILACS-Express | LILACS, LIPECS | ID: biblio-1522151

ABSTRACT

Se presenta un análisis de la composición florística, formas de vida, importancia y estrategias para la conservación de un bosque relicto de la Vertiente Occidental Andina del norte del Perú, descrito por primera vez y denominado La Oscurana (caserío El Nogal, distrito Bolívar, provincia San Miguel de Pallaques, Cajamarca; 6°90'S y 79°08'O, 2000-2800 m). El análisis preliminar incluye 85 familias, 169 géneros y 258 especies de plantas vasculares, de las cuales 15 familias corresponden a Pteridophyta y 70 a Magnoliophyta. En los ámbitos genérico y específico las Asteraceae son las mejor representadas de las Magnoliopsida y las Orchidaceae de las Liliopsida. Las formas de vida predominantes en cuanto a familia se reúnen en seis categorías: hierbas con 29 familias (34%), arbustos con 14 (16%), árboles con 9 (11%), trepadoras/lianas con 9 (11%), hierbas/arbustos con 7 (8%) y hierbas/epífitas con 5 familias (6%). Se encontró que además de albergar una diversidad excepcional y brindar utilidad económica local, muchas de las especies no están registradas en las vertientes occidentales andinas del norte y del sur. Por la importancia que posee y por ser uno de los últimos bosques relictos existentes, la conservación legal de éste frágil ecosistema es urgente. Se propone que debe ser declarada zona de protección o intangible y que su conservación debe ser integral, involucrando a científicos, Estado, gobiernos regionales, gobiernos locales y población.


Floristic composition, the life forms, the importance and strategies for the conservation of a newly discovered relict forest in the north of Peru, called La Oscurana, are analyzed (El Nogal Hamlet, Bolívar District, San Miguel de Pallaques Province, Cajamarca Department; 6° 90' S y 79° 08' W, 2000-2800 m). The preliminary analysis includes 85 families, 169 genera and 258 species of vascular plants, 15 families are Pteridophyta and 70 Magnoliophyta. The family with the most genera and species are the Asteraceae in the Magnoliopsida, and the Orchidaceae in the Liliopsida. The predominant life forms of the families can be divided in 6 different categories: herbs 29 (34%), shrubs 14 (16%), trees 9 (11%), lianas 9 (11%), herbs/shrubs 7 (8%) and epiphytes 5 (6%). The exceptional diversity and the local economic use are discussed. The conservation of this fragile and important ecosystem is urgent. It is one of the last existing relict forests in the region. The forest should be declared as a protected zone. Scientists, state officials, members of the regional government and the local people should work out together in the conservation plan.

10.
Rev. peru. biol. (Impr.) ; 12(2)ago. 2005.
Article in Spanish | LILACS-Express | LILACS, LIPECS | ID: biblio-1522155

ABSTRACT

El presente trabajo se llevó a cabo con la finalidad de conocer la composición de las fanerógamas del Santuario Regional de Piura Manglares San Pedro de Vice-Sechura. Su importancia radica en que es el manglar más austral del Pacífico de Sudamérica. Dicho trabajo fue realizado desde abril del 2000 hasta febrero del 2004. Para la realización del presente estudio se realizaron visitas periódicas cada dos meses al lugar, se colectaron las plantas bajo procedimientos estándar. Las muestras se determinaron en el lugar y algunas fueron llevadas al laboratorio de Botánica de la Universidad Nacional de Piura y al laboratorio de Botánica Fanerogámica de la Universidad Nacional de Trujillo para su determinación definitiva; luego, las muestras se depositaron en el herbario en formación de la Universidad Nacional de Piura. El manglar consiste en primer lugar de árboles y arbustos de Avicennia germinans (L.) L. (Verbenaceae) «mangle prieto». En el presente inventario se documentan un total de 44 especies de fanerógamas correspondiendo a 36 géneros en 21 familias para el manglar.


The present work was carried out with the aim to document the composition of the flowering plants of the Regional Sanctuary of Piura «Manglares San Pedro», of Vice-Sechura. Its importance resides in that it is the most southern mangrove forest in the Pacific of South America. The study was carried out from April of the 2000 until February of the 2004. For the realization of the present work periodic visits every two months to the place were undertaken, the plants were collected under the standard procedures. The samples were determined in the place and some were taken to the laboratory of Botany of the National University of Piura and the laboratory of Phanerogamic Botany of the National University of Trujillo for their definitive determination, then the samples were deposited in the Herbarium in formation of the National University of Piura. The mangrove forest primarily consists of trees and shrubs of Avicennia germinans (L.) L. (Verbenaceae) «mangle prieto». The present inventory reports 44 species of phanerogams belonging to 36 genera in 21 families from the Mangrove.

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