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1.
Biota Neotrop. (Online, Ed. ingl.) ; 22(2): e20211318, Mar 31, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1403616

ABSTRACT

Abstract: Cerrado remnants can hold an important diversity of plant species of environmental and ecological relevance. We presented a checklist of vascular plants based on 12 years of inventory carried out in 36 plots (10 m x 2 m; 0.18 ha in total) and during unsystematic walks in a remnant area of cerrado sensu stricto located at Itirapina municipality, state of São Paulo, southeastern Brazil. The list comprised 195 plant species, corresponding to 54 families and 131 genera. The richest families were Fabaceae (25 species), Asteraceae (16), Myrtaceae (16), Rubiaceae (11), Bignoniaceae and Malpighiaceae (10 each), Melastomataceae (9), and Erythroxylaceae, Sapindaceae and Annonaceae (6). Predominant life forms included shrubs and trees, with 68% of the species, followed by lianas with 12%, sub-shrub and herbs with 10% each. Bees were the dominant pollinators (67,5%) and the majority of species had seeds dispersed by animals (56.8%), mostly by birds, followed by wind (33.3%) and self-dispersed (11.2%). More than 60% of the total species were classified as "typical" Cerrado species. Bowdichia virgilioides was the only species classified as Near Threatened (NT) and 157 were regarded as Data Deficient (DD). Our dataset provides floristic, structural, and ecological information for one of the targeted areas for Cerrado survey at São Paulo state, contributing to the understanding of diversity patterns and future conservation and restoration actions in this threatened hotspot.


Resumo: Apresentamos uma lista de verificação de plantas vasculares baseada em 12 anos de inventário realizado em 36 parcelas (10 m x 2 m; 0,18 ha no total) e caminhadas assistemáticas em uma área remanescente de cerrado sensu stricto localizada em Itirapina, município do estado de São Paulo, sudeste do Brasil. A lista é composta por 195 espécies de plantas, correspondendo a 54 famílias e 131 gêneros. As famílias mais ricas foram Fabaceae (25 espécies), Asteraceae (16), Myrtaceae (16), Rubiaceae (11), Bignoniaceae e Malpighiaceae (10 cada), Melastomataceae (9) e Erythroxylaceae, Sapindaceae e Annonaceae (6). As formas de vida predominantes incluíram arbustos e árvores (33,7% das espécies), seguidas por lianas (12%), arbustos e ervas (10%). As abelhas foram os polinizadores dominantes (67,5%) e o principal modo de dispersão foi a zoocoria (56,8%), representada principalmente por pássaros, seguida por vento (33.3 %) e auto (11.2 %). Mais de 60% das espécies encontradas foram classificadas como espécies "típicas" de Cerrado. Bowdichia virgilioides foi a única espécie pertencente a uma categoria de ameaça "Quase Ameaçada (NT)", sendo 157 delas classificadas na categoria "Deficiente de Dados (DD)". Nosso conjunto de dados fornece informações florísticas, estruturais e ecológicas para uma das áreas-alvo do levantamento do Cerrado no estado de São Paulo, sudeste do Brasil, contribuindo para a compreensão dos padrões de diversidade e futuras ações de conservação neste hotspot ameaçado.

2.
Biota Neotrop. (Online, Ed. ingl.) ; 21(4): e20211238, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1339276

ABSTRACT

Abstract: The associations between morphological fruit types, fruit and seed colors, and functional plant traits: life forms, epiphytism, physiology, nutritional relationships, fruit phenology, and successional stage, were determined for 1,139 plant species from contrasting plant communities. Texture and dehiscence were closely related. Dehiscence is largely associated with dry tissues; indehiscence, however, is an attribute of both dry and fleshy fruits. The number of morphological fruit types was 28 or 55 for Gray's and Spjut's classifications, respectively. Fruits were predominantly dark in color (brown, purple-black, black or green), whilst seeds had both dark and light colors (brown, beige, or black). The most representative associations were mainly found between the more abundant fruit types and the colors most common. Asymmetries in the level of specialization, whereby less common fruit and seed colors tended to be associated with the most common fruit types, were also found. Fleshy fruits showed more variation as regards their coloration, and only drupes and berries showed a tendency towards a specific color: purple-black. The relationships among fruit type and color, seed color, and functional plant traits revealed the following trends: trees produced both fleshy and dry fruits; shrubs produced fleshy fruits; and herbaceous species, dry fruits. Woody species tended to have dark or bright colors, depending on their seed dispersal mechanisms and phylogenetic relations. Epiphytes were associated with dry-dehiscent fruits and brown seeds, and parasitic-hemiparasitic species had predominantly fleshy-indehiscent fruits. Pioneer species were more likely to have dry fruits, whereas fleshy fruits tended to be more frequent in late successional stage species. The C4 species, mostly herbs, had mainly one-seeded dry fruits, but multi-seeded fruits in succulent-CAM species showed morphologically diverse fruit types. Unripe and ripe fruits showed seasonal changes, especially during the rainy-dry transition period for the most abundant morphological fruit types, dry fruits during the dry period and fleshy fruited species was positively associated with the rainy season. All these trends are discussed with regard to their environmental significance and the relationships between fruit morphology, colors and functional groups. .


Resumen: Las asociaciones entre tipos morfológicos de frutos, colores de frutos y semillas y los grupos funcionales de las plantas: formas de vida, epifitismo, fisiología, relaciones nutricionales, fenología de frutos y estado sucesional fueron determinados para 1139 especies de plantas de comunidades contrastantes. La textura y dehiscencia estaban muy relacionadas. Dehiscencia está estrechamente asociada con tejidos secos, pero indehiscencia es un atributo de frutos secos y carnosos. El número de tipos morfológicos de frutos fue 28 y 55 para la clasificación de Gray y Spjut respectivamente. Los frutos fueron predominantemente de colores oscuros (marrón, negro-purpura, negro o verdes), mientras que las semillas tenían colores claros y oscuros (marrón, beige o negro). Las asociaciones más representativas fueron principalmente encontradas entre los tipos de frutos más abundantes y los colores más comunes. También se encontraron asimetrías en los niveles de especialización, donde los colores menos comunes de frutos y semillas estuvieron asociados con los tipos de frutos más comunes. Los frutos carnosos mostraron más variación en su coloración, y solo las drupas y bayas tendieron a colores específicos como negro-purpura. Las relaciones entre tipo de fruto y color, color semilla y rasgos funcionales de las plantas revelaron las siguientes tendencias: arboles producen frutos secos y carnosos; arbustos frutos carnosos y hierbas producen frutos secos. Las especies leñosas tendieron a tener colores oscuros y brillantes, relacionados con su mecanismo de dispersión y filogenia. Epifitas estuvieron asociadas con frutos secos dehiscentes y semillas marrones, y las especies parásitas-hemiparásitas tenían predominantemente frutos carnosos indehiscentes. Las especies pioneras tenían comúnmente frutos secos, mientras que los frutos carnosos tendieron a ser más frecuentes en especies de estados sucesionales tardíos. Las especies C4, principalmente hierbas, tenían frutos secos con una semilla, mientras que frutos polispermos en especies CAM mostraron diversos tipos de frutos. La fenología de frutos maduros e inmaduros mostro cambios estacionales para los más abundantes tipos morfológicos, especialmente durante el periodo de transición lluvia-sequia, frutos secos en el periodo seco y frutos carnosos durante el periodo lluvioso. Todas estas tendencias son discutidas con relación a las características ambientales y de acuerdo con las relaciones entre tipos morfológicos de frutos, colores y grupos funcionales.

3.
Rev. biol. trop ; 65(3): 1215-1225, Jul.-Sep. 2017. tab, ilus
Article in English | LILACS-Express | LILACS | ID: biblio-897616

ABSTRACT

Abstract:In the Parana basin, the Serra de Maracaju juxtaposes the Seasonal Dry Forest and the cerradão (a phytophysiognomy of Cerrado), two distinct vegetation types that differ in canopy height, tree density, and composition of the understory. In the same way, these differences may be reflected in the composition of climbing plant species found in these two forest types. Thus, in this study we compared the climbing species in two forest fragments of Serra de Maracaju to understand: (1) Are species richness and floristic composition of climbing plants similar in cerradão and seasonal deciduous forest?, (2) What degree of floristic compositional difference exists between the two vegetation types?, (3) Do the two vegetation types differ significantly in climbing mechanisms, life forms, and dispersal syndromes represented among climbing species? For this, we established and sampled four plots per forest type over 24 months. Species were identified and each one classified, based on three discrete traits. Proportional differences were analyzed using chi-square tests. Our results showed that species richness and floristic composition of climbing plants in the cerradão and the seasonal deciduous forest were not similar. Climber species richness in cerradão was 37 while in the seasonal deciduous forest it was 31; they share only 13 species. Four families, Dioscoreaceae, Fabaceae, Malpighiaceae, and Sapindaceae, included over 60 % of the climbing species. The morphological traits most common in both forest types were herbaceous life form, apical twining mechanism, and wind dispersal. Dioscoreaceae was found to be the dominant family, but is the first time to be reported for this condition in Brazil. Bignoniaceae and Passifloraceae ocurred only in the cerradão, and Asteraceae and Combretaceae in the seasonal deciduous forest; some species were found exclusively in a type of forest. Floristic composition of the cerradão and seasonal deciduous forest fragments were substantially different, in spite of physical proximity. However, their climbing species are not statistically distinct in morphological characteristics, possibly due to uniform climatic conditions and the similarity of species because of a shared ancestry (similar families). Rev. Biol. Trop. 65 (3): 1215-1225. Epub 2017 September 01.


Resumen:La Serra de Maracaju yuxtapone los distintos tipos de vegetación de la floresta seca estacional y del cerradón (la fitofisiognomía del cerrado). Los dos tipos de vegetación son distintos en altura de copa, densidad de árboles y composición del sotobosque. Estas diferencias deben reflejarse en la composición de especies de plantas trepadoras que se encuentran en los dos tipos de bosque. Especies trepadoras de dos fragmentos forestales de la Serra de Maracaju han sido comparadas para responder: (1) ¿La riqueza de especies y composición florística de trepadoras es similar en el cerradón y en la floresta estacional decidua? (2) ¿Cuáles especies distinguen los dos tipos vegetacionales de otros? (3) ¿Los dos tipos vegetacionales difieren significativamente en mecanismo de ascensión, formas de vida y síndrome de dispersión en las especies trepadoras? Cuatro parcelas por tipo de floresta han sido muestreadas durante 24 meses. Las especies fueron identificadas y caracterizadas en tres rasgos discretos. Las diferencias proporcionales fueron analizadas usando el test chi-cuadrado. La riqueza y composición florística de trepadoras no fue similar en las dos formaciones: 37 especies en el cerradón y 31 en la floresta estacional decidua, con 13 especies compartidas. Dioscoreaceae, Fabaceae, Malpighiaceae y Sapindaceae corresponden al 60 % de las especies trepadoras. Las formaciones poseen características comunes como la forma de vida herbácea, el mecanismo de ascensión voluble y la anemocoria. La familia predominante fue Dioscoreaceae, no prevalente en estudios en Brasil. A pesar de la proximidad geográfica, la composición florística de los fragmentos de cerradón y de la floresta estacional decidua difiere substancialmente. Las características morfológicas de las especies no difieren estadísticamente, posiblemente por las condiciones climáticas uniformes y la fuerte similitud entre las composiciones florísticas de las familias.

4.
Rev. biol. trop ; 63(4)Oct.-Dec. 2015.
Article in English | LILACS-Express | LILACS | ID: biblio-1507459

ABSTRACT

he structure, dynamics and density of plant populations in different ecosystems are controlled by climatic seasonality. Seed rain contributes to both establishment and maintenance of the forest as well as to the recovery of disturbed areas near forest fragments. The aim of this study was to assess the deposition rate of different seeds of endemic and exotic tree species for the edge and for the interior of the forest matrix. The study area is a four hectares forest fragment located on the campus of the Federal University of Ceará. To measure seedrain, 80 collectors were suspended 20cm above the ground in the gradient. Samples were collected monthly for 12 months (June 2009May 2010), the material was screened in the laboratory and the diaspores (fruits and seeds) were quantified and taxonomically identified. We found 23 383 seeds belonging to 38 families and 89 different species, with a density of 134.48 seeds per m². The families Rubiaceae and Fabaceae were the most representative ones, with more quantities of seeds. The deposition of the seed rain was influenced by season and, consequently, by temperature and rainfall. There was a clear difference between the edge and the forest interior; with a large supply of native, animal dispersed and late successional seeds on the inside, and a considerable number of seeds belonging to nonnative species and abiotic dispersion on the edge. Small fragments like this one can serve as important sources of seed for adjacent degraded areas, which demonstrate the importance of conservation and management of small fragments to avoid the degradation caused by edge effects. Rev. Biol. Trop. 63 (4): 981994. Epub 2015 December01.


aestructura,dinámicaydensidad de poblaciones de plantas en diferentes ecosistemas son controladas por estacionalidad climática. La lluvia de semillas contribuye tanto al establecimiento y mantenimiento de los bosques, así como a la recuperación de áreas alteradas cerca de los fragmentos de bosque. El objetivode este estudio es evaluar la tasa de deposición de diferentes semillas de especies endémicas y exóticas de árboles tanto al borde y como al interior del bosque. El área de estudio es un fragmento de bosque de 4 hectáreas ubicado en el campus de la Universidad Federal de Ceará. Para medir la lluvia de semillas, 80 recolectores fueron suspendidos a 20 cm del suelo. Las muestras fueron recolectadas mensual mente durante un año (Junio 2009Mayo 2010), elmaterial fue analizado en el laboratorio y las diásporas (frutos y semillas) fueron cuantificadas e identificadas taxonómicamente. Encontramos 23 383 semillas pertenecientes a 38 familias y 89 especies, con una densidad de 1 134.48 semillas m². Las familias Rubiaceae y Fabaceae fueron las más representativas, con mayor cantidad de semillas. La deposición de la lluvia de semillas fue influenciada por la estacionalidad y, en consecuencia por la temperatura y la precipitación.Existeunaclaradiferenciaciónentreelborde y el interior del bosque, una gran cantidad de semillas nativas con dispersión por animales y de dispersión tardía están presentes en el interior del bosque, comparado a un considerable número de semillas pertenecientes a especies no nativas con dispersión abiótica en el borde del bosque. Fragmentos pequeños como este pueden servir como una fuente importante de semillas para las áreas degradadas adyacentes, lo que demuestra la importancia dela conservación y manejo de pequeños fragmentos para evitar la degradación causada por los efectos de borde.

5.
Article in English | IMSEAR | ID: sea-162216

ABSTRACT

Aims: The study was designed to explore the floristic composition and biological characteristics. Place and Duration of Study: A record of plant species of Sheikh Maltoon Town Mardan was organized during 2008 – 2009. Methodology: A record of plant species was organized on the source of field trips conducted in winter, summer and monsoon, and identified with available literature. The plants were classified into different life form and leaf size classes after standard methods. Results: The flora consisted of 91 plant species belonging to 76 genera and 38 families. Asteraceae, Poaceae and Cucurbitaceae are the dominant families of the floristic composition of research area. The biological spectrum explains that therophytes (52 spp., 57.14%), magaphanerophytes (11 spp., 12.09%) were the dominant followed by hemicryptophytes (9 spp., 9.89%), chamaephytes (8 spp., 8.79%), nanophanerophytes (6 spp., 6.59%), geophytes (4 spp., 4.39%) and parasite (1 spp., 1.1%). Leaf spectra of plants consisted of microphylls (46.2%), mesophylls (25.3%), nanophylls (13.2%), leptophylls (9.59%) and megaphylls (5.49%). Conclusion: Analysis of the present work reveals the phytoclimate to be of therophytic type. The domination of therophytes indicates that the investigated area is under deep biotic stress.

6.
Braz. j. biol ; 68(2): 329-339, May 2008. graf, tab
Article in English | LILACS | ID: lil-486758

ABSTRACT

Whether the functional structure of ecological communities is deterministic or historically contingent is still quite controversial. However, recent experimental tests did not find effects of species composition variation on trait convergence and therefore the environmental constraints should play the major role on community convergence into functional groups. Seasonal cerrados are characterized by a sharp seasonality, in which the water shortage defines the community functioning. Hyperseasonal cerrados experience additionally waterlogging in the rainy season. Here, we asked whether waterlogging modifies species convergences into life-forms in a hyperseasonal cerrado. We studied a hyperseasonal cerrado, comparing it with a nearby seasonal cerrado, never waterlogged, in Emas National Park, central Brazil. In each area, we sampled all vascular plants by placing 40 plots of 1 m² plots in four surveys. We analyzed the species convergences into life-forms in both cerrados using the Raunkiaer's life-form spectrum and the index of divergence from species to life-form diversity (IDD). The overall life-form spectra and IDDs were not different, indicating that waterlogging did not affect the composition of functional groups in the hyperseasonal cerrado. However, there was a seasonal variation in IDD values only in the hyperseasonal cerrado. As long as we did not find a seasonal variation in life-form diversity, the seasonal variation of convergence into life-forms in the hyperseasonal cerrado was a consequence of the seasonal variation of species diversity. Because of high functional redundancy of cerrado plants, waterlogging promoted a floristic replacement without major changes in functional groups. Thus, waterlogging in the hyperseasonal cerrado promoted seasonal changes in species convergence into life-forms by reducing species diversity.


Se a estrutura ecológica das comunidades é determinística ou historicamente dependente é ainda um tema controverso. Entretanto, testes experimentais recentes não encontraram efeitos da variação da composição de espécies na convergência de traços funcionais e, portanto, as restrições ambientais devem ter um papel principal na convergência das comunidades em grupos funcionais. Cerrados estacionais são caracterizados por uma estacionalidade pronunciada, em que a seca define o funcionamento da comunidade. Cerrados hiperestacionais experimentam adicionalmente um alagamento na estação chuvosa. Aqui, perguntamo-nos se o alagamento modifica a convergência de espécies em formas de vida em um cerrado hiperestacional. Para tanto, estudamos um cerrado hiperestacional, comparando-o com um cerrado estacional, nunca alagado, no Parque Nacional das Emas, GO. Em cada cerrado, usamos 40 parcelas de 1 m² e amostramos todas as plantas vasculares. Analisamos a convergência de espécies em formas de vida usando o espectro biológico de Raunkiaer e o índice de divergência entre a diversidade de espécies e de formas de vida (IDD). Os espectros gerais e os IDDs não diferiram, indicando que o alagamento não afetou a composição dos grupos funcionais no cerrado hiperestacional. Entretanto, houve uma variação estacional nos valores de IDD somente no cerrado hiperestacional. Como não observamos variações estacionais na diversidade de formas de vida, a variação da convergência no cerrado hiperestacional foi uma conseqüência da variação estacional da diversidade de espécies. Devido à elevada redundância funcional das plantas do cerrado, o alagamento promoveu substituições florísticas sem maiores mudanças nos grupos funcionais. Portanto, o alagamento promoveu mudanças estacionais na convergência de espécies em formas de vida, reduzindo a diversidade de espécies.


Subject(s)
Biodiversity , Plants/classification , Seasons , Brazil , Population Density , Population Dynamics
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