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1.
PeerJ ; 12: e17460, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38952991

RESUMEN

A taxonomic revision of Rhizophora L. (Rhizophoraceae) in Thailand is presented. Two species, R. apiculata Blume and R. mucronata Poir., are enumerated with updated morphological descriptions, illustrations and a taxonomic identification key, together with notes on distributions, habitats and ecology, phenology, conservation assessments, etymology, vernacular names, uses, and specimens examined. Three names in Rhizophora, are lectotypified: R. apiculata and two associated synonyms of R. mucronata (i.e., R. latifolia Miq. and R. macrorrhiza Griff.). R. longissima Blanco, a synonym of R. mucronata, is neotypified. All two Rhizophora species have a conservation assessment of Least Concern (LC). Based on the morphological identification, these two species can be distinguished from one another by the shape and width of the leaf laminae and the length of a terminal stiff point of the leaf laminae; the type and position of the inflorescences and the number of flowers per inflorescence; the character and color of the bracteoles; the presence or absence of the flower pedicels; the shape of the mature flower buds; the shape, color, and texture of the sepals; the shape, character, and the presence or absence of hairs of the petals; the number of stamens per flower; the size of the fruits; the color and size of the hypocotyls; the color and diameter of the cotyledonous cylindrical tubes; and the color of the colleters and exudate. The thick cuticles, sunken stomata, large hypodermal cells, and cork warts are adaptive anatomical features of leaves in Rhizophora that live in the mangrove environments. The pollen grains of Thai Rhizophora species are tricolporate, prolate spheroidal or oblate spheroidal shapes, small-sized, and reticulate exine sculpturing.


Asunto(s)
Rhizophoraceae , Tailandia , Rhizophoraceae/anatomía & histología , Ecosistema , Hojas de la Planta/anatomía & histología
2.
Sci Total Environ ; 942: 173757, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-38851329

RESUMEN

This study identified the occurrence of Holocene chronology hiatuses in the sedimentary record of the Patos-Mirim system caused by river avulsion processes, as well as evidence of sharp anthropogenic changes in the surrounding region of the lagoon water bodies. The presence of chronology hiatuses demonstrates the importance of considering the disturbance effect of paleo-drainage processes on the paleoenvironmental resolution and expression of the sedimentary record of such coastal plains. Anthropogenic activities especially those related to agriculture and forestry have increased significantly during the great acceleration, resulting in modifications of both the landscape and the environmental conditions of the lagoon bodies. Such impacts were clearly reflected in the sedimentary record where abrupt changes in palynological trends, sedimentary DNA, isotopic and granulometric analyses were inferred. The climatic conditions combined with regressive sea level can explain the chronology hiatuses. Pollen analyses demonstrated changes in the landscape, particularly indicated by the shift from Cyperaceae to Poaceae dominance after the 1960 CE. Therefore, all proxies together demonstrate the modification in the landscape and changes in the environment, clearly influenced by anthropogenic action from unsustainable agricultural practices.


Asunto(s)
Agricultura , Monitoreo del Ambiente , Sedimentos Geológicos , Ríos , Movimientos del Agua
3.
Sci Total Environ ; 922: 171157, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38412879

RESUMEN

Throughout history, humans have relied on wood for constructions, tool production or as an energy source. How and to what extent these human activities have impacted plant abundance and composition over a long-term perspective is, however, not well known. To address this knowledge gap, we combined 44,239 precisely dated tree-ring samples from economically and ecologically important tree species (spruce, fir, pine, oak) from historical buildings, and pollen-based plant cover estimates using the REVEALS model from 169 records for a total of 34 1° × 1° grid cells for Central Europe. Building activity and REVEALS estimates were compared for the entire study region (4-15°E, 46-51°N), and for low (<500 m asl) and mid/high elevations (≥500 m asl) in 100-year time windows over the period 1150-1850. Spruce and oak were more widely used in wooden constructions, amounting to 35 % and 32 %, respectively, compared to pine and fir. Besides wood properties and species abundance, tree diameters of harvested individuals, being similar for all four species, were found to be the most crucial criterion for timber selection throughout the last millennium. Regarding land use changes, from the 1150-1250's onwards, forest cover generally decreased due to deforestation until 1850, especially at lower elevations, resulting in a more heterogeneous landscape. The period 1650-1750 marks a distinct change in the environmental history of Central Europe; increasing agriculture and intense forest management practices were introduced to meet the high demands of an increasing population and intensifying industrialization, causing a decrease in palynological diversity, especially at low elevations. Likely the characteristic vegetation structure and composition of contemporary landscapes originated from that period. We further show that land use has impacted vegetation composition and diversity at an increasing speed leading to a general homogenization of landscapes through time, highlighting the limited environmental benefits of even-aged plantation forestry.


Asunto(s)
Bosques , Pinus , Humanos , Anciano , Europa (Continente) , Madera , Polen , Agricultura Forestal , Conservación de los Recursos Naturales
4.
Environ Monit Assess ; 196(2): 194, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38265534

RESUMEN

Interpretation of a fossil pollen data for the vegetation and climate reconstruction of any region needs a modern pollen-vegetation analogue for its calibration. We analyzed the surface sediments and moss polsters for the pollen and microcharcoal records to understand the modern pollen-vegetation relationship and human activities in the Baspa Valley, Kinnaur, Himachal Pradesh. Presently, valley is occupied by the arboreal and non-arboreal vegetation of temperate to subalpine habitats and land use activities. The recovered pollen assemblages showed variability in the dispersal behavior of pollen of taxa growing along the valley transect and also captured the signals of human activities over land use. The overall dominance of arboreal pollen in the recovered pollen assemblage corresponds with the dominant growth of conifers and broadleaf tree taxa and represents the valley vegetation at a regional scale. However, the profuse pollen production of a few arboreal taxa and long distance pollen transport from one vegetation zone to other by the strong upthermic valley winds could bias the pollen representation of in-situ vegetation. The high pollen frequency of non-arboreal taxa in the open meadows represents the near vicinity to their plant source. Human activities like fire burning and cultivation by the local population are evident by the recovery of microcharcoal particles and pollen of plants belonging to Cerealia Poaceae, Asteraceae, Amaranthaceae, Polygonaceae, Rosaceae, Juglandaceae, etc. The dataset taken as modern pollen-vegetation analogue is useful to assess past changes in the vegetation and land cover in relation to climate and human factors for future sustenance.


Asunto(s)
Ambiente , Monitoreo del Ambiente , Humanos , Himalayas , Polen , Clima
5.
Artículo en Inglés | MEDLINE | ID: mdl-38147285

RESUMEN

This review is engaged in determining the capability of plant pollen as a significant source of evidence for the linkage between suspects and crime location in forensic sciences. Research and review articles were collected from Google Scholar, the Web of Science, and PubMed. Articles were searched using specific keywords such as "Forensic Palynology," "Pollen metabarcoding," "Plant forensics," and "Pollen" AND "criminal investigation." Boolean logic was also utilized to narrow the articles to be included in this review article. Through the literature and exploratory research, it has been observed in the current study that with advancements in technology, forensic palynology has found its application in creating an association between the crime scene and suspected individuals to have a link to it, as pollen DNA is a long-lasting investigative tool that can effectively help forensic investigations. Moreover, the literature shows that the DNA of pollen and spores has helped forensic scientists link suspects to crime scenes, and the introduction of pollen DNA metabarcoding tools has eased the efforts of palynologists to analyze pollen DNA. The introduction of DNA metabarcoding techniques to analyze pollen from plants has helped identify the geological locations of the plants and ultimately identify the culprit.

6.
Rev. biol. trop ; 71(1)dic. 2023.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1449501

RESUMEN

Introducción: No conocemos estudios sobre la microsporogénesis de la planta de cacao, y poco se sabe sobre la ultraestructura de sus granos de polen. Objetivo: Describir la microsporogénesis y ultraestructura de los granos de polen en T. cacao. Métodos: Procesamos más de 30 flores para cada etapa floral, teñidas con Safranina-Azul Alcian, PAS-Amidoblack y Lacmoid. Para la microscopía de transmisión procesamos las muestras en resina y las teñimos con azul de toluidina. Para microscopía electrónica de barrido, fijamos y deshidratamos en 2.2-dimetoxipropano, secamos hasta un punto crítico y recubrimos con oro. Resultados: Anteras diferenciadas por una masa celular en los extremos distales a los filamentos estaminales. Durante el desarrollo la pared de las anteras presenta varios estratos celulares y al madurar se reducen a la epidermis y al endotecio. Las células madre de microsporas se dividen por meiosis para formar tétradas. El tapete es secretor e intacto hasta que se liberan los granos, para luego degenerar. Los granos de polen son isopolares, esferoidales, pequeños, tricolpados. La ultraestructura presenta una esporodermis semitectada, con ornamentación reticulada, y un retículo heterobrochado con el muri sin ornamentación. La exina se deposita antes que la intina. Los orbículos son individuales, lisos y de tamaño variado. Hay abundante polenkit en el tectum y entre las columelas. La intina es delgada, pero se desarrolla ampliamente en las áreas del colpo, formando una intina interna compacta y una intina externa inusual con una apariencia columelada. Conclusión: La estructura y el desarrollo de las anteras siguen el patrón de las angiospermas. La microsporogénesis simultánea y la deposición centrípeta de la esporodermis se conocen de Malvaceae, pero los caracteres de la intina son nuevos para la familia.


Introduction: We know of no studies on the microsporogenesis of the cocoa plant, and little is known about the ultrastructure of its pollen grains. Objective: To describe microsporogenesis and ultrastructure of pollen grains in T. cacao. Methods: We processed over 30 flowers for each floral stage and stained with Safranin-Alcian Blue, PAS-Amidoblack and Lacmoid. For transmission microscopy we processed samples on resin and stained with toluidine blue. For scanning electron microscopy, we fixed and dehydrated in 2.2-dimethoxypropane, critically dried and coated with gold. Results: Anthers differentiated by a cellular mass at the ends distal to the staminal filaments. During development, the anther wall has several cellular layers reduced, at maturity, to the epidermis and endothecium. Microspore mother cells divide by meiosis to form tetrads. The tapetum is secretory and intact until the grains are released, to later degenerate. Pollen grains are isopolar, spheroidal, small, tricolpate. Ultrastructure has a semi-tectate sporodermis, with reticulate ornamentation, and heterobrochated reticulum with the muri without ornamentation. Exine is deposited before intine. The orbicles are individual, smooth, and varied in size. There is abundant pollenkitt on the tectum and between the columellae. The intine is thin, but develops widely in the colpus areas, forming a compact internal intine and an unusual external intine with a columellated appearance. Conclusion: Anther structure and development follows the angiosperm pattern. Simultaneous microsporogenesis and centripetal deposition of the sporodermis are known from Malvaceae, but intine characters are novel for the family.

7.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1551106

RESUMEN

Diversos estudios demuestran que la inclusión de polinizadores, como las abejas Apis mellifera, generan efectos positivos sobre la productividad de cultivos de durazno (Prunus persica). Esto lleva a probar metodologías que estimulen a las abejas para visitar, con mayor frecuencia, el cultivo de interés, sugiriendo el uso de la técnica de osmoguiado, como herramienta para potencializar el efecto de la polinización. Este estudio valoró un protocolo de osmoguiado, para estimular híbridos africanizados de Apis mellifera, a recolectar polen de flores de durazno, utilizando, como indicador indirecto, el análisis palinológico en muestras de polen. Los tratamientos utilizados fueron con osmoguiado y sin osmoguiado. Cada tratamiento contó con tres colmenas y el periodo de evaluación fue de cinco semanas, coincidiendo con el mayor periodo de floración del durazno. Los resultados evidenciaron que este protocolo no logró estimular a las abejas a visitar la flor de durazno para la búsqueda de polen. La disponibilidad permanente de otras plantas productoras de polen, reportadas previamente como importantes en el aporte de este recurso, pudo influir en la selección de fuentes por parte de las abejas. El polen obtenido provino, principalmente, de plantas de las familias Fabaceae, Asteraceae, Malvaceae y Passifloraceae.


Several studies show that the inclusion of pollinators such as honeybee Apis mellifera generates positive effects in the productivity of peach (Prunus persica) crops. It led to test methodologies that stimulate bees to improve the visit of crops of interest, suggesting the use of the osmoguiding technique, as a tool to potentiate the effect of pollination. This study evaluated an osmoguided protocol to stimulate Africanized hybrids of Apis mellifera to collect pollen from peach flowers, using palynological analysis of pollen samples as an indirect indicator. The treatments used were with osmoguided and without osmoguided. Each treatment had three hives, and the evaluation period was five weeks, coinciding with the peak flowering period of the peach. The results showed that this protocol did not stimulate the bees to visit the peach blossom to search pollen. The permanent availability of other pollen-producing plants, previously reported as significant in the contribution of this resource, could influence bee source selection. The pollen obtained came mainly from plants of the families Fabaceae, Asteraceae, Malvaceae, and Passifloraceae.

8.
Rev. biol. trop ; 69(3)sept. 2021.
Artículo en Español | LILACS, SaludCR | ID: biblio-1387673

RESUMEN

Resumen Introducción: Los estudios sobre microsporogénesis, micromorfología y estructura de los granos de polen en Malvaceae son escasos. Objetivos: Describir el proceso de microsporogénesis y aspectos micromorfológicos de los granos de polen en A. rosea. Métodos: Se procesaron más de 30 andróforos de acuerdo con los protocolos estándar para incrustar y seccionar en parafina. Las secciones obtenidas se tiñeron con Azul de Safranina-Alcian, las anteras inmaduras y no fijadas se tiñeron con Azul de anilina. Se procesaron secciones de resina adicionales de los andróforos y se tiñeron con azul de toluidina. Se observaron secciones ultrafinas con microscopía electrónica de transmisión (MET). Para la observación con microscopía electrónica de barrido (MEB), el material se fijó y deshidrató en 2,2 dimetoxipropano, luego se secó hasta un punto crítico y se recubrieron con oro. Resultados: las anteras se diferencian de una masa celular en los extremos distales de los filamentos del estambre. La pared de la antera madura presenta una capa externa de células epidérmicas y una capa interna, el endotecio. Las células madre de microesporas se dividen por mitosis y luego experimentan meiosis para formar tétradas. El tapete es inicialmente celular y forma una sola capa de células y luego pierde integridad celular al invadir el lóculo de microsporangio, formando un periplasmodio. Durante la formación de la esporodermis, primero se deposita la exina y luego la intina. Para el momento de la liberación de los granos de polen, el tapete se ha degenerado por completo. Los granos de polen son pantoporados, apolares, con simetría radial, esferoidales, con espinas, báculas, gránulos y microgránulos. El téctum está perforado con fovéoleas dispuestas homogéneamente en toda la superficie y con polenkit. La exina es ancha (5-6 µm) y consta de una endexina gruesa de 3.5 a 4 µm y una ektexina fina (0.6-0.7 µm). La ultraestructura muestra columelas claramente definidas formando el infratéctum. Se aprecian tricomas nectaríferos unicelulares glandulares capitados (TG) cubriendo toda la superficie de los filamentos de los estambres. Conclusiones: La estructura y desarrollo de las anteras sigue los patrones conocidos de las angiospermas. La microsporogénesis simultánea y el depósito centrípeto de la esporodermis se han descrito previamente para Malvaceae.


Abstract Introduction: Studies on microsporogenesis, micromorphology and structure of pollen grains in Malvaceae are scarce. Objectives: To describe the process of microsporogenesis and micromorphological aspects of pollen grains in A. rosea. Methods: Androphores were processed according to standard protocols for sectioning in paraffin. The obtained sections were stained with Safranin-Alcian blue, Aniline blue was used for immature and unfixed anthers and for resin sections of the androphores, Toluidine blue. Ultrathin sections were observed with transmission electron microscopy. For observation with scanning electron microscopy the material was fixed and dehydrated in 2.2 dimethoxypropane, dried to a critical point and coated with gold. Results: Anthers differentiate from a cell mass at the distal ends of the stamen filaments. The wall of the mature anther presents an outer layer of epidermal cells and an inner layer, the endothecium. Microspore mother cells divide by mitosis and then undergo meiosis to form tetrads. The tapetum is initially cellular and forms a single layer of cells and then loses cellular integrity by invading the microsporangium locule, forming a periplasmodia, by the time the pollen grains are released it degenerated. During sporodermis formation, exine is first deposited and then intine. Pollen grains are pantoporate, apolar, with radial symmetry, spheroidal, with spines, bacula, granules and microgranules. Tectum is perforated with foveolae arranged homogeneously over the whole surface and pollenkit is present. Exine is broad and consists of a thick 3.5 to 4 µm endexine and a thin ektexine (0.6-0.7 µm). The ultrastructure shows columellae forming the infratectum. Capitate glandular unicellular nectariferous trichomes covers the whole surface of the stamen filaments. Conclusions: The structure and development of the anthers follows the known patterns for angiosperms. Simultaneous microsporogenesis and centripetal deposit of the sporodermis have been previously described for Malvaceae.


Asunto(s)
Polen , Malvaceae/anatomía & histología , Gametogénesis en la Planta
9.
Rev. biol. trop ; 69(2)jun. 2021.
Artículo en Español | LILACS, SaludCR | ID: biblio-1387634

RESUMEN

Resumen Introducción: A pesar de que T. cacao es una especie importante a nivel mundial por la producción de cacao, es poco lo que se conoce sobre la micromorfología y estructura de las anteras y los granos de polen. Objetivos: Describir y analizar la estructura y micromorfología de las anteras y los granos de polen de 10 genotipos élite de esta importante especie tropical. Métodos: Se tomaron más de 30 anteras de flores en antesis de los 10 genotipos élite de T. cacao del banco de germoplasma ex situ del Centro de Investigaciones Suiza-Agrosavia (Rionegro, Santander-Colombia). El material se procesó de acuerdo con los protocolos estándar para embeber y seccionar en parafina. Las secciones obtenidas (3 μm) se tiñeron con azul de Safranina-Alcian para discriminar estructuras con paredes primarias y secundarias y polifenoles totales. Además, se usó la técnica PAS-Amidoblack para diferenciar entre polisacáridos estructurales y de reserva, así como proteínas. Para la determinación de esporopolenina y polifenoles se usó la tinción azul de toluidina y finalmente para descripciones adicionales se aplicó la tinción azul alcián-PAS-hematoxilina. Las observaciones se realizaron mediante microscopio fotónico y microscopio de epifluorescencia. Para la observación con microscopía electrónica de barrido (MEB), las anteras con los granos de polen se fijaron y deshidrataron en 2.2 dimetoxipropano, luego se desecaron hasta un punto crítico y finalmente se recubrieron con oro. Resultados: Las anteras son bitecas y están sostenidas por un largo filamento formado por un estrato epidérmico, tejido parenquimatoso y un haz vascular. La dehiscencia ocurre longitudinalmente a través del estomio. La pared de la antera madura está formada por una capa epidérmica monoestratificada, una capa de células endoteliales con engrosamientos fibrilares lignificados y se pueden apreciar restos celulares del tapete y abundantes orbículas recubriendo la cavidad de los microesporangios. Los tejidos epidérmicos y parenquimatosos de las anteras almacenan polifenoles. Las orbículas son generalmente esféricas, psiladas y exhiben las mismas reacciones de tinción y fluorescencia que la exina de los granos de polen. Los granos de polen son mónades, isopolares, pequeños (16-19 µm) con amb circular, esferoidales, tricolpados con colpos medianos o cortos (5-10 µm) con membrana ornamentada, semitectatos, reticulados, heterobrochados, las paredes del retículo ornamentadas o no, con microgránulos de diferente tamaño o escabrados. Los análisis estadísticos mostraron que existen diferencias significativas en el tamaño de los granos de polen (P ˂ 0.05). Se observa que los granos de polen más pequeños son los del genotipo TCS 19 (16.890 µm) y se diferencian del resto de genotipos, y entre estos no se observan diferencias significativas. Solo dos genotipos (SCC 19 y SCA 6) presentaron polenkit y solo uno tiene paredes perforadas (SCA 6). Conclusiones: La estructura y micromorfología de las anteras de T. cacao son similares a las descritas para otras Malvaceae. Así mismo, los granos de polen mostraron variaciones de tamaño, ornamentación de las paredes y del lumen del retículo y presencia de polenkit. Sin embargo, no se observó relación entre las variaciones de los caracteres micromorfológicos analizados en los granos de polen y los modelos de compatibilidad polínica reportados para estos genotipos.


Abstract Introduction: Despite the fact that T. cacao is an important species worldwide for cocoa production, little is known about the micromorphology and structure of anthers and pollen grains. Objectives: To describe and analyze the structure and micromorphology of the anthers and pollen grains of 10 elite genotypes of this important tropical species. Methods: More than 30 anthers of flowers in anthesis were taken of the 10 elite genotypes of T. cacao from the ex situ germplasm bank of the Suiza-Agrosavia Research Center (Rionegro, Santander-Colombia). The anthers with the pollen grains were fixated and processed according to the standard protocols for embedding and sectioning in paraffin. Sections obtained (3 μm thick) were stained with Safranin-Alcian blue to discriminate structures with primary and secondary walls and total polyphenols. Additionally, the samples were also stained with the PAS-Amidoblack technique was used to differentiate between structural and reserve polysaccharides as well as proteins. Toluidine blue staining was used for the determination of sporopollenin and polyphenols and finally Alcian blue-PAS-Hematoxylin staining was applied for additional descriptions. Observations were made using photonic microscopy and epifluorescence microscopy. For observation with scanning electron microscopy (SEM) the anthers with the pollen grains were fixed and dehydrated in 2.2 Dimethoxypropane, then desiccated to critical point and finally coated with gold. Results: The anthers are dithecal and supported by a long filament made up of an epidermal stratum, parenchymal tissue, and a vascular bundle. The dehiscence occurs longitudinally through the stomium. The anther wall is made up of a monostratified epidermal layer, followed by a layer of endothecial cells with lignified fibrillar thickenings, cellular remnants of tapetum and abundant orbicules can be seen covering the cavity of the microsporangia. The epidermal and parenchymal tissues of the anthers are abundant in polyphenols. Orbicules are generally spherical, psilated, and these exhibit the same staining and fluorescence reactions as exine from pollen grains. The pollen grains are monades, isopolar, small (16-19 µm) with circular amb, spheroidal, tricolpate with medium or short colpi (5-10 µm) with sculptured membrane, semitectate, reticulated, heterobrochate, sculptured or non- sculptured walls, with microgranules of different size or scabrate. The statistical analyzes showed that there are significant differences in the size of the pollen grains (P ˂ 0.05). It is observed that the smallest pollen grains are those of the TCS 19 genotype (16.890 µm) and are different from the other genotypes, and among these there are no significant differences. Only two genotypes (SCC 19 and SCA 6) showed pollenkit and only one has perforated walls (SCA 6). Conclusions: The structure and micromorphology of the anthers of T. cacao are similar to those described for other Malvaceae. Likewise, the pollen grains showed variations in size, ornamentation of the sporoderm and the lumen of the reticulum and the presence of pollenkitt. However, no relationship was observed between the micromorphological characters analyzed in the pollen grains and the pollen compatibility models reported for these genotypes.


Asunto(s)
Polen/anatomía & histología , Cacao
10.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-786641

RESUMEN

There is often the risk of confusing pollen grains with helminth eggs from archaeological sites. Thousands to millions of pollen grains can be recovered from archaeological burial sediments that represent past ritual, medication and environment. Some pollen grain types can be similar to parasite eggs. Such a confusion is represented by the diagnosis of enterobiasis in ancient Iran. The authors of this study confused a joint-pine (Ephedra spp.) pollen grain with a pinworm egg. This paper describes the specific Ephedra pollen morphology that can be confused with pinworm eggs.


Asunto(s)
Adolescente , Femenino , Humanos , Arqueología , Entierro , Diagnóstico , Huevos , Enterobiasis , Enterobius , Ephedra , Helmintos , Irán , Óvulo , Parásitos , Polen
11.
Rev. biol. trop ; 66(4): 1536-1546, oct.-dic. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1003344

RESUMEN

Abstract Stingless bees are located in the tropic areas, and produced a sweet natural substance called pot honey, with different properties and uses. Recently, most studies are focused on characterizing them, in order to contribute to their knowledge and the establishment of quality laws. Thus physicochemical, acceptance and palynological studies were performed in stingless bee honeys from Soconusco, Chiapas, in order to learn and contribute to their knowledge in the Tropics. Nine honey samples were collected from Melipona solani (Ms), M. beecheii (Mb) and Scaptotrigona mexicana (Sm) in different meliponaries. Our results registered physicochemical values that ranged as follow; pH 2.8-4.8, electrical conductivity (EC) 114-1211 μS/cm, free acidity 24-100 meq/kg, aw 59-71 g/100g, moisture 35-38 %, color 0.13-0.75 Pfund scale, reducing sugars 47-71 %, hidroxymethylfurfural (HMF) not determined - 2.72 mg/100g, and diastase activity 1.92-11.22 DN. On the other hand, the principal component analysis (PCA) of physicochemical values showed that 86.9 % of the total variability between species was explained by the following parameters aw, moisture, free acidity, color, pH, sugars and EC. Sm honeys were associated (PCA) with a higher water content, free acidity and darker colors, while Melipona honeys with a sweeter taste and a lower diastase activity; thus honeys could be grouped by genera. The acceptance test showed that 78 % of honeys were preferred, being the SmCa sample in the category "I likely dislike" due to the bitter taste (disapproved by consumers). The melisopalynological results showed that M. beecheii honeys are monofloral with a 45 % of Fabaceae pollen, while Melipona solani and Scaptotrigona mexicana honeys are multi or polyfloral with diferent pollen types; Fabaceae, Melastomataceae, Malvaceae and Asteraceae. From this complementary study we can asume that it is necessary to implicate researchers with producers, so they could have accesss to stingless bee honey analysis and to help them to improve meliponaries management by identifying and introducing stingless bee flora.(AU)


Resumen En las regiones tropicales se ubican las abejas sin aguijón, las cuales producen una sustancia dulce denominada miel de cántaro con propiedades y usos diferentes a los de las abejas melíferas (Apis mellifera). Actualmente, se han desarrollado diversos trabajos enfocados a su caracterización, con la finalidad de contribuir con su conocimiento y el establecimiento de estándares de calidad. En este estudio se realizaron estudios fisicoquímicos, de aceptación y palinológicos en mieles de abejas sin aguijón de Soconusco, Chiapas. Se recolectaron nueve muestras de miel de las siguientes especies: Melipona solani (Ms), M. beecheii (Mb) y Scaptotrigona mexicana (Sm) en diferentes meliponarios. Nuestros resultados registraron valores fisicoquímicos que variaron de la siguiente manera: pH 2.8-4.8, conductividad eléctrica (CE) 114-1 211 μS/cm, acidez libre 24-100 meq/kg, aw 59-71 g/100 g, humedad 35-38 %, color 0.13-0.75 escala Pfund, azúcares reductores 47-71 %, hidroximetilfurfural (HMF) no determinado - 2.72 mg/100 g, y actividad de la días-tasa 1.92-11.22 ND. Por otro lado, el análisis del componente principal (PCA) de los valores fisicoquímicos mostró que el 86.9 % de la variabilidad total entre las especies se explica por los siguientes parámetros: aw, humedad, acidez libre, color, pH, azúcares y CE. Las mieles de Sm (PCA) se asociaron con un mayor contenido de agua, acidez libre y colores más oscuros, mientras que las mieles de Melipona con un sabor más dulce y una actividad de días-tasa más baja; por lo tanto, las mieles podrían agruparse por géneros. La prueba de aceptación mostró que el 78 % de las mieles eran preferidas, siendo la muestra de SmCa en la categoría "Probablemente no me gusta" debido al sabor amargo (desaprobado por los consumidores). Los resultados melisopalinológicos mostraron que las mieles de M. beecheii son monoflorales con un 45 % de polen de Fabaceae, mientras que las mieles de M. solani y S. mexicana son multi o poliflorales con diferentes tipos de polen: Fabaceae, Melastomataceae, Malvaceae y Asteraceae. De este estudio complementario observamos que se requiere poner en contacto a investigadores y productores, para que el acceso a los análisis de las mieles de abejas sin aguijón sea posible, y así mismo se pueda ayudar con el mejoramiento del manejo de los melionarios al momento de identificar e introducir la flora preferida por las abejas sin aguijón.(AU)


Asunto(s)
Polen , Abejas , Fenómenos Químicos , Miel , Zona Tropical
12.
Rev. biol. trop ; 66(3): 1182-1196, jul.-sep. 2018. tab, graf
Artículo en Español | LILACS, SaludCR | ID: biblio-977376

RESUMEN

Resumen En el noroeste de Argentina, los bosques subtropicales de las Yungas son de gran importancia por la gran diversidad vegetal. Las abejas melíferas (A. mellifera) utilizan estos recursos para su alimentación y en consecuencia como un servicio ecosistémico a través de la apicultura. La caracterización de la flora polinífera de una región permite conocer la fuente de alimento y definir la importancia de las diferentes especies vegetales para el desarrollo y mantenimiento de las colonias. El objetivo del presente trabajo es identificar la flora polinífera utilizada por A. mellifera en el sector oeste de las Yungas en Jujuy (Argentina) a través de la caracterización de sus cargas corbiculares y analizar las variaciones a lo largo de la primavera y verano de dos periodos productivos consecutivos. Para ello, se analizaron 14 muestras tomadas mensualmente a la largo de los periodos setiembre 2011 a marzo 2012 y setiembre 2012 a marzo de 2013. Las muestras se obtuvieron a través de trampas caza polen en las entradas de las colmenas y tratadas en el laboratorio según las técnicas convencionales de melisopalinología con posterior acetólisis. Se identificaron un total de 46 tipos polínicos pertenecientes a 25 familias botánicas. Las más importantes de acuerdo a los valores de índice de importancia de familia son: Euphorbiaceae (35.54), Fabaceae (26.27), Asteraceae (20.77), Vitaceae (16.14) y Myrtaceae (9.13). Asimismo, los principales recursos poliníferos fueron Eucalyptus, Eupatorium, Mimosa, Parapiptadenia excelsa, Sebastiania, Viguiera, Zanthoxylum, tipo Cissus y representantes de las familias Cactaceae y Euphorbiaceae. Las variaciones del índice de amplitud de nicho trófico evidencian para la zona una selección de recursos florales, donde se destaca la utilización de especies nativas. La información generada en este estudio, aporta al conocimiento del recurso ofrecido por el bosque y las especies que son de importancia para la producción apícola. Además, de contribuir a potenciar la producción y comercialización de este producto a partir de su valor agregado, permitiendo a los apicultores un buen manejo de las colmenas.


Abstract In Northwest Argentina, Yungas subtropical forests are very important because of their huge vegetal diversity. Honeybees (A. mellifera) use these resources to feed and therefore as an ecosystemic service through beekeeping. The characterization of pollen flora of a region allows getting to know the food source and defining the importance of different plant species for colonies development and maintenance. The aim of the present study is to identify the pollen flora used by A. mellifera in the Yungas Western area in Jujuy (Argentina) by means of their pollen loads characterization and to analyze the variations of two consecutive productive periods throughout spring and summer. To do this, 14 samples taken monthly were analyzed over the periods from September 2011 to March 2012 and September 2012 to March 2013. The samples were obtained from pollen traps at the entrances of the hives and were treated in the laboratory under conventional melisopalinology techniques with subsequent acetolysis. A total of 46 pollen types belonging to 25 botanical families were identified. The most important ones according to the family importance index are Euphorbiaceae (35.54), Fabaceae (26.27), Asteraceae (20.77), Vitaceae (16.14), Myrtaceae (9.13). Zanthoxylum, Sebastiania, Mimosa, Euphorbiaceae, Cactaceae, Parapiptadenia excelsa, Eupatorium, Cissus, Eucalyptus y Viguiera were identified as dominant resources. The variations of the breadth Index trophic niche show a floral resources selection for the area, where the use of native species stands out. The information produced in this study contributes to the knowledge of the resource offered by the forest and the species that are important for beekeeping production. Besides, it contributes to enhance the production and marketing of this product from its added value, allowing beekeepers a good management of hives. Rev. Biol. Trop. 66(3): 1182-1196. Epub 2018 September 01.


Asunto(s)
Animales , Argentina , Polen , Abejas , Dieta , Polinización , Apicultura , Agricultura Forestal
13.
An. acad. bras. ciênc ; 89(4): 2581-2595, Oct.-Dec. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886839

RESUMEN

ABSTRACT This paper presents a paleoenvironmental reconstruction from palynological analyses of a sedimentary core of Holocene age, drilled at municipality of Garopaba (Santa Catarina), Southern Brazil. A total of 46 samples was collected for palynological analyses in the 450 cm-long core PCSC-3, as also three samples for radiocarbon dating and granulometric analyses. The palynological content includes 84 taxa related to pollen grains of angiosperms (38) and gimnosperm (3), spores of pteridophyta (16) and bryophyta (2), spores of fungi (8), algae (3), acritarchs (3), dinoflagellate cysts (2) and microforaminiferal linings (1). Three specimens of acritarchs are described and illustrated in detail. Three palynological phases were defined based on changes in assemblages: Phase I, Phase II and Phase III. The Phase I is characterized as a lagoonal paleoenvironment with marine influence from the beginning of the sedimentation (5390 cal yr BP), based on occurrences of acritarchs, dinoflagellate cysts and microforaminiferal linings. The Phase II (3032 yr BP until 858 cal yr BP) also is characterized by a lagoonal paleoenvironment, however, presented decrease in percentage of marine elements and increase in freshwater algae record, suggesting less marine influence in the lagoonal body. In Phase III (last 856 years), underwater sedimentation prevailed, under swamp-like conditions.

14.
Rev. biol. trop ; 65(2): 799-806, Apr.-Jun. 2017. tab, ilus
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-897581

RESUMEN

AbstractJatropha curcas is a native Mexican plant, distributed in the forests of coastal regions; it has shown potential for the production of biofuel, and its raw protein can be used as animal feed. Nevertheless, its current varieties have low yield and production variability, as it is in domestication period. The knowledge of the pollen grains is fundamental for studies of Jatropha reproductive biology and breeding for genetic improvement to generate new hybrids and improve fruit and seed yield. This study compared pollen morphology of four Jatropha species, which include two varieties of J. curcas (one toxic from India and one non-toxic from Mexico), and two varieties of wild J. cinerea (Sinaloa and Baja California Sur); additionally, pollen was collected from wild J. platyphylla (Sinaloa) and J. vernicosa (Baja California Sur) to characterize them palynologically. We used a scanning electron microscope to describe the size and shape of pollen grains. Pollen grains were observed spheroidal. The diameter of the varieties of toxic and non-toxic J. curcas and that of J. platyphylla were 58 ± 2.3, 54 ± 1.7, and 51 ± 2.4 µm, respectively; the number of clavae was 84 ± 10, 108 ± 15, and 180 ± 15.5, respectively. Pollen grains of J.cinerea (Sinaloa) had a diameter of 50 ± 1.7 µm and 220 ± 14 clavae by area; J. cinerea (Baja California Sur) had a diameter of 45 ± 1.9 µm and 195 ± 14.7 clavae. Pollen grains of J. vernicosa had a diameter of 46 ± 2.1 µm and 231 ± 25.6 clavae. The ornamentation of the exine showed clava with capita gemma shaped for varieties of J.curcas species and clavum shaped for J. platyphylla, J. cinerea and J. vernicosa species. The studied varieties have a cross-linked endexine and ectexine intectate. Luminal bacules were observed in the reticular space of J. curcas varieties while none were present in the varieties of J. cinerea, J. platyphylla, and J. vernicosa.


ResumenJatropha curcas es nativa de México, y se distribuye en los bosques de las regiones costeras; las plantas han mostrado potencial para la producción de biodiesel, y la proteína cruda puede utilizarse para alimentación animal. Sin embargo, sus variedades actuales tienen bajo rendimiento y variabilidad en la producción, por estar en periodo de domesticación. El conocimiento de los granos de polen es fundamental para el estudio de la biología reproductiva de Jatropha y mejoramiento genético para generar nuevos híbridos y mejorar el rendimiento de frutos y semillas. Este estudio compara la morfología del polen de cuatro especies de Jatropha, que incluyen dos variedades de J. curcas, (una tóxica de India y una no tóxica de México) y dos variedades silvestres de J. cinerea (Sinaloa y Baja California Sur), por último, se obtuvo polen de J. platyphylla (Sinaloa) y J. vernicosa (Baja California Sur) silvestres para caracterizarlos palinológicamente. Para describir el tamaño y la forma de los granos de polen, se utilizó un microscopio electrónico de barrido. Los granos de polen tienen forma esferoidal. El diámetro de las variedades de J. curcas tóxica y no tóxica, y J. platyphylla fueron 58 ± 2.3, 54 ± 1.7, y 51 ± 2.4 micras, respectivamente; el número de clavas fue de 84 ± 10, 108 ± 15 y 180 ± 15.5, respectivamente. Los granos de polen de J. cinerea (Sinaloa) tienen un diámetro de 50 ± 1.7 micras y 220 ± 14 clavas por zona; J. cinerea (Baja California Sur) tiene un diámetro de 45 ± 1.9 micras y 195 ± 14.7 clavas. Los granos de polen de J. vernicosa tienen un diámetro de 46 ± 2.1 micras y 231 ± 25.6 clavas. La ornamentación de la exina mostró clavas con cápita en forma de gema y pequeños báculos en el lumen para ambas J. curcas y en forma de clavum para J. cinerea, J. platyphylla y J. vernicosa y no presentan báculos en el lumen. Las variedades estudiadas tienen una endexina reticulada y ectexina intectada.

15.
Arq. ciênc. vet. zool. UNIPAR ; 20(4): 247-251, out.-dez. 2017.
Artículo en Portugués | VETINDEX, LILACS | ID: biblio-883114

RESUMEN

A Palinologia é responsável pelo estudo do pólen de angiospermas, esporos de pteridófitas e de fungos, cistos de algas, dinoflagelados, foraminíferos acritarcas e partículas de carvão. Três hipóteses embasam as análises palinológicas: (1) a chuva polínica vigente reflete a vegetação presente na área em estudo; (2) o acúmulo e a conservação dos palinomorfos não prejudicam a personificação da chuva polínica; e (3) a amostragem, o processamento químico, a contagem e a identificação dos palinomorfos reconstituem fielmente a chuva polínica da área. A aplicação da Palinologia nos diversos ramos da ciência torna-se viável graças à imensa variabilidade morfológica presente no pólen (ou nos palinomorfos), o que possibilita definir famílias, gêneros e espécies botânicas. As relações entre abelhas e plantas podem ser feitas por meio da análise do pólen transportado pelas fêmeas ou daquele armazenado em células de cria ou em potes de alimento. A interação entre abelhas e plantas está relacionada ao processo de polinização, responsável pela renovação da flora de vários ecossistemas.(AU)


Palynology is responsible for the study of angiosperms pollen, pteridophyte and fungal spores, algae cysts, dinoflagellates, actinic foraminifera and charcoal particles. Three hypotheses support palynological analyzes: (1) the pollen rain reflects the vegetation present in the study area; (2) the accumulation and conservation of palynomorphs do not impair the personification of pollen rain; and (3) the sampling, chemical processing, counting, and identification of palynomorphs faithfully reconstitute the pollen rain area. The application of palynology in the various branches of science becomes feasible due to the immense morphological variability present in pollen (or palynomorphs), which makes it possible to define families, genera and botanical species. The relationships between bees and plants can be made through the analysis of pollen carried by the female animals or stored in the breeding cells or food pots. The interaction between bees and plants is related to the pollination process, responsible for the renewal of the flora of several ecosystems.(AU)


La Palinología es responsable por el estudio del polen de angiospermas, esporos de pteridofitas y de hongos, quistes de algas, dinoflagelados, foraminíferos, acritarcas y partículas de carbón. Tres hipótesis embazan los análisis palinológicos: (1) la lluvia polínica vigente refleja la vegetación presente en el área en estudio; (2) el acúmulo y la conservación de los palinomorfos no perjudican la personificación de la lluvia polínica; y (3) el muestreo, el procesamiento químico, el conteo y la identificación de los palinomorfos reconstituyen fielmente la lluvia polínica del área. La aplicación de la Palinología en los diversos seguimientos de la ciencia se hace viable gracias a la inmensa variabilidad morfológica presente en el polen (o en los palinomorfos), lo que posibilita definir familias, géneros y especies botánicas. Las relaciones ente abejas y plantas pueden ser hechas a través del análisis del polen transportado por las hembras o de aquel almacenado en células de cría o en potes de alimentos. La interacción entre abejas y plantas está relacionada al proceso de polinización, responsable por la renovación de la flora de varios ecosistemas.(AU)


Asunto(s)
Abejas/enzimología , Polinización , Tubo Polínico
16.
Braz. j. biol ; 75(4): 821-829, Nov. 2015. tab
Artículo en Inglés | LILACS | ID: lil-768213

RESUMEN

Abstract Eucalyptus plantations are frequently used for the establishment of bee yards. This study was carried on at Fazenda Brejão, northwestern region of the State of Minas Gerais, Brazil. This farm is covered both with native Cerrado vegetation (Brazilian savanna) and eucalyptus plantations. This paper reports on the botanic origin of pollen pellets and honey collected from honeybee (Apis mellifera) hives along a thirteen-month period (January 2004 to January 2005). The most frequent pollen types found in the pollen pellets during the rainy season were Trema micrantha (Ulmaceae), Copaifera langsdorffii (Fabaceae), an unidentified Poaceae, unidentified Asteraceae-2, Cecropia sp. 1 (Cecropiaceae) and Eucalyptus spp. (Myrtaceae); during the dry season the most frequent pollen types were Acosmium dasycarpum (Fabaceae), Cecropia sp. 1 (Cecropiaceae) and Eucalyptus spp. (Myrtaceae). Pollen grains of Baccharis sp. (Asteraceae), Cecropia sp. 1 (Cecropiaceae), Copaifera langsdorffii (Fabaceae), Mimosa nuda (Fabaceae), Eucalyptus spp. (Myrtaceae) and Trema micrantha (Ulmaceae) were present in the honey samples throughout the study period.


Resumo Plantações de Eucalyptus são, frequentemente, utilizadas como locais de instalação para colmeias. Este estudo foi realizado na Fazenda Brejão, localizada no noroeste de Minas Gerais, Brasil. Esta fazenda é coberta por Cerrado nativo (savana brasileira) e por plantações de eucaliptos. Este trabalho indica a origem botânica de bolotas e mel coletados em colmeias de Apis mellifera por um período de 13 meses (Janeiro/2004 a janeiro/2005). Os tipos polínicos mais frequentes nas amostras de pólen durante a estação chuvosa foram Trema micrantha (Ulmaceae), Copaifera langsdorffii (Fabaceae), Poaceae, Asteraceae não identificada 2, Cecropia sp. 1 (Cecropiaceae) e Eucalyptus spp. (Myrtaceae); na estação seca, os tipos polínicos mais frequentes foram Acosmium dasycarpum (Fabaceae), Cecropia sp. 1 (Cecropiaceae) e Eucalyptus spp. (Myrtaceae). As espécies Baccharis sp. (Asteraceae), Cecropia sp. 1 (Cecropiaceae), Copaifera langsdorffii (Fabaceae), Mimosa nuda (Fabaceae), Eucalyptus spp. (Myrtaceae) e Trema micrantha (Ulmaceae) estiveram presentes durante todo o período amostrado.


Asunto(s)
Animales , Abejas/fisiología , Ambiente , Miel/análisis , Polen/química , Brasil , Eucalyptus/crecimiento & desarrollo , Agricultura Forestal , Pradera , Estaciones del Año
17.
Acta amaz ; 45(2): 215-230, abr.-jun. 2015. map, ilus, tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1455244

RESUMEN

The Bananal Island is regarded the largest fluvial island in the world, bounded by Araguaia and Javaés rivers, being located in southwest of Tocantins. The objectives of this work were to provide information about the vegetational changes that occurred at the Bananal Island, in order to contribute to the understanding the dynamics of past and current savanna and areas of ecotones with forests. Thus, a sedimentary core collected from a small lake at the Bananal Island plain was submitted to pollen and radiocarbon dating analyses. The results showed that the last millennium was dominated by forest reflecting a wet climate. At the beginning of the record (920-770 yr cal BP) the wet climate and high rainfall produced flooding during long rainy seasons that maintained the Javaés River connected to the studied lake, and hence, this environment was marked by the presence of a homogenous forest rich in Moraceae/Urticaceae, due to flooded soils occurrence. During the following period (770-304 yr cal BP) the reduced rainfall and shortening of the rainy seasons isolated the lake from the Javaés River for long periods, which caused a diversification of the forest and gave rise to the appearance of the components of floodplain forest and marsh vegetation adapted to waterlogged soils. Since 304 years cal BP to the present day this environment remained dominated by this diverse forest and the lacustrine conditions were also similar to previous phase, with a slight increase of moisture in the last 84 years that caused the increase of Piranhea.


A Ilha do Bananal é considerada a maior ilha fluvial do mundo, margeada pelos Rios Araguaia e Javaés, sendo localizada na porção sudoeste do Estado do Tocantins. Os objetivos deste trabalho foram obter informações sobre as mudanças na vegetação ocorridas na Ilha do Bananal, de forma a contribuir para o entendimento da dinâmica pretérita e atual da vegetação de cerrado e áreas de ecótonos com floresta. Assim, um testemunho sedimentar coletado em um pequeno lago na planície da Ilha do Bananal foi submetido às análises polínica e de datação por radiocarbono. Os resultados mostraram que o ultimo milênio foi dominado por floresta refletindo um clima úmido. No início do registro (920-770 anos cal AP) o clima úmido e a alta pluviosidade produziram inundações durante longos períodos chuvosos que mantiveram o rio Javaés conectado ao lago estudado, e assim, este ambiente foi marcado pela presença de uma floresta homogênea rica em Moraceae/Urticaceae, devido à ocorrência de solos alagados. Durante o período seguinte (770-304 anos cal AP) a pluviosidade reduzida e o encurtamento dos períodos chuvosos isolaram o lago do rio Javaés por longos períodos, que causou a diversificação da floresta e deram origem ao aparecimento de componentes da vegetação de floresta de planície de inundação e brejos adaptados a solos úmidos. Desde 304 anos cal AP até o presente este ambiente tem sido dominado por esta floresta diversificada e as condições lacustres também foram similares ao período anterior, com um ligeiro aumento de umidade nos últimos 84 anos o que causou o aumento de Piranhea.


Asunto(s)
Factores de Tiempo , Bosques , Pradera , Humedales
18.
An. acad. bras. ciênc ; 83(3): 939-952, Sept. 2011. mapas, tab
Artículo en Inglés | LILACS | ID: lil-595546

RESUMEN

Historians claim that European colonizers of the northern coast of Rio de Janeiro State found vast herbaceous fields when arrived in this region. Hypotheses about the origin of these fields include forest burning by the Goitacás indians and periodical floods by the Paraíba do Sul River and the lagoon system. The palynologycal analysis of two lake cores obtained in the municipality of Campos dos Goytacazes revealed opening episodes of hygrophilous forest and the establishment of field vegetation, recorded at ca. 6,500 and ca. 4,000 14C yr BP. The partial replacement of forest by field vegetation in the first episode was probably caused by floods of the lower areas during the development of the Holocene lagoon phase. During the second episode, successions of vegetational patterns occurred due to lowering of the sea level. Drying and enlarging of the coastal plain have allowed its colonization by herbs and heliophyte plants. The palynological analysis does not provide any evidence that sustains the theories of use of fire and agricultural activities by indigenous groups during these periods.


Os historiadores citam que os europeus colonizadores da costa norte do Estado do Rio de Janeiro encontraram vastos campos herbáceos quando chegaram a essa região. As hipóteses sobre a origem desses campos incluem aplicação de "queimada"pelos índios Goitacás e periódicas inundações do rio Paraíba do Sul e sistemas lagunares. A análise palinológica de dois testemunhos de sondagem obtidos no município de Campos dos Goytacazes revelou epsódios de abertura da floresta higrófila e o estabelecimento da vegetação campestre, datado sem ca. 6.500 e 4.000 14C anos AP. O primeiro epsódio de substituição parcial da floresta pela vegetação campestre se deu provavelmente pelas inundações das áreas baixas durante o desenvolvimento da fase lagunar holocênica. No segundo epsódio, os padrões de sucessão da vegetação ocorreram como consequência do abaixamento do nível do mar. O ressecamento e a progressão da planície costeira permitiram sua colonização pelas plantas herbáceas heliófitas. A análise palinológica não forneceu qualquer evidência que apoie as teorias do uso do fogo e da prática de atividades agrícolas por grupos indígenas durante esses períodos.


Asunto(s)
Radioisótopos de Carbono/análisis , Sedimentos Geológicos/análisis , Paleontología , Polen , Árboles , Brasil
19.
Acta amaz ; 41(1): 9-20, mar. 2011. ilus, graf, mapas, tab
Artículo en Portugués | LILACS, VETINDEX | ID: lil-574691

RESUMEN

A porção superior (1,25m) do testemunho de sondagem Bom Jesus (TBJ), coletado no limite campo-mangue da Fazenda Bom Jesus, município de Soure, ilha do Marajó, Pará, Brasil, foi estudada através de análise palinológica de alta resolução objetivando a determinação da composição, abundância e diversidade de tipos polínicos bioindicadores de modificações na paleovegetação durante o Holoceno. 16 amostras sedimentares de 2cm³ foram tratadas de acordo com metodologia padrão em palinologia. Os programas Tilia e Tilia Graph foram utilizados para a construção dos diagramas palinológicos de abundância e concentração. A base do testemunho foi datada por 14C em 2730 ± 40 anos A.P. Foram definidas três zonas palinológicas. A presença de pólen de Rhizophora com abundância máxima de 88 por cento apontou dominância de mangue ao longo de todo o testemunho sedimentar. Variações recorrentes na hidrodinâmica da baía do Marajó, caracterizadas por pulsos erosivos de curto período, parecem ter provocado redução na dominância de mangue. O incremento na abundância de tipos polínicos bioindicadores de campo inundável associados a elementos de restinga e floresta, evidenciam a migração do campo inundável sobre o manguezal. Os dados indicam correlação com outros registros polínicos holocênicos de transgressão marinha para a costa norte amazônica no Holoceno Superior.


The upper portion (1.25 m) of the sediment core Bom Jesus (TBJ), was collected in the field-mangrove limit of Bom Jesus Farm, municipality of Soure, island of Marajó, Pará, Brazil, was studied through pollen analysis high resolution aimed at determining the composition, abundance and diversity of the pollen types bioindicators of changes in the palaeobotany. 16 samples of sedimentary 2cm³ were treated according to standard methodology. Tilia and Tilia Graph software were used for to construct abundance and concentration palinological diagrams. The core base was dated by 14C in 2730 ± 40 years AP. Three palynological zones were identified. The mangrove ecosystem was dominant all sedimentary sequence of the TBJ core and was represented mainly for Rhizophora pollen type, which reaches 88 percent of the maximum relative abundance. Variations applicant hydrodynamics in the Marajó bay, characterized by short pulses of erosive period, seem to have caused reduction in the dominance of mangroves. The increase in the abundance of types growth bioindicators of field associated with elements of swamp forest and restinga, indicate the migration of the field on the mangrove swamp. The data show correlation with other palynological records of Holocene marine transgression to the north coast in the Upper Amazon Holocene.


Asunto(s)
Ecosistema Amazónico , Humedales
20.
An. acad. bras. ciênc ; 82(3): 679-690, Sept. 2010. graf, mapas
Artículo en Inglés | LILACS | ID: lil-556804

RESUMEN

Palynological analysis of pollen, Pteridophyta spores and algae deposited in the superficial sediments at Lagoa de Cima and Lagoa do Campelo Lakes, located in the north of Rio de Janeiro state, was used to determine the spatial variation of the palynomorphs deposition. A total of 67 pollen types were identified at Lagoa de Cima, with an expressive contribution of regional arboreous taxa, hydrophytes and ruderal plants of the pastureland. The depositional pattern of palynomorphs depends on the fluvial leakage, the proximity of the local sedimentation to the inlet of the Imbé and Urubu Rivers and the bathymetry of lake bottom. The highest concentrations of palynomorphs were observed in the decentralized and less deeper area, without the interference of the northeastern wind. At Lagoa do Campelo, a total of 58 pollen types were identified, among which the majority of the pollen grains came from hydrophytes, with the highest concentrations found along the northeastern shore. The southeastern shore showed high percentages of pollen and spores with degraded exine and mechanical damage, due to the transport through the lakeby the currents caused by the wind, confirmed by the depositional trend of damaged palinomorphs along the same direction as the prevailing winds.


A análise palinológica de grãos de pólen, esporos de Pteridophyta e algas depositados nos sedimentos superficiais da Lagoa de Cima e Lagoa do Campelo, norte do Rio de Janeiro, foi usada para a avaliação da variação espacial de deposição dos palinomorfos. Um total de 67 tipos polínicos foi identificado na Lagoa de Cima, com expressiva contribuição de taxons arbóreos regionais, plantas hidrófitas e ruderais de pastagens. O padrão deposicional dos palinomorfos está sujeito às vazões fluviais, à proximidade do local de sedimentação em relação à desembocadura dos rios Imbé e Urubu e à batimetria do leito da lagoa. As maiores concentrações de palinomorfos foram observadas em áreas descentralizadas e menos profundas, não interferindo a ação dos ventos NE. Já na Lagoa do Campelo foi identificado um total de 58 tipos polínicos, em sua maioria de grãos de pólen de hidrófitas, com área de maior concentração relacionada à borda nordeste. A borda sudoeste apresentou altas percentagens de pólen e esporos com a exina degradada e danos mecânicos, resultado da ação de correntes aquáticas impulsionadas pelo vento, confirmando ser a tendência deposicional dos palinomorfos danificados a mesma da direção dos ventos dominantes.


Asunto(s)
Agua Dulce , Sedimentos Geológicos/análisis , Paleontología , Polen/clasificación , Brasil , Fósiles
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