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Dissertations |
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1
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PEDRO HENRIQUE SALOMÃO GANANÇA
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A HETEROGENEIDADE DE BANCOS DE MACRÓFITAS AQUÁTICAS COMO PREDITOR DA ESTRUTURA ESPACIAL DA ASSEMBLÉIA DE SAPOS EM LAGOS AMAZÔNICOS
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Advisor : ALFREDO PEDROSO DOS SANTOS JUNIOR
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COMMITTEE MEMBERS :
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ALFREDO PEDROSO DOS SANTOS JUNIOR
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SAMUEL CAMPOS GOMIDES
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PAULO SÉRGIO BERNARDE
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Igor Luis Kaefer
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Data: Feb 3, 2020
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Show Abstract
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Investigating the effects of environmental gradients on assemblage spatial structure is relevant to understand mechanisms and processes affecting biodiversity. Environmental gradients may act as ecological filters limiting species occurrence and abundance, which generates non-random patterns of habitat occupancy. Environmental filtering-mediated biodiversity emerges from relationships between environmental gradients and estimates of α- and β-diversity. Such relationships have been widely demonstrated in frog assemblages occupying forests in Amazonia but are rarely assessed in non-forest ecosystems such as macrophyte banks in lakes. Macrophyte banks may vary spatially in terms of width, height, and species composition, in response to physicochemical parameters of water. Therefore, it is reasonable to expect spatially heterogeneous frog assemblages in response to variation in habitat vertical stratification and perch shape. In this study we sampled 50 plots covering 15 km2 of continuous macrophyte banks to test the effects of distance from the lake bank, water depth, macrophyte height and composition (proportions of morphotype occupancy), pH, dissolved oxygen and temperature on frog α-diversity and β-diversity estimates. We found 16 species, for which local distribution was not random but characterized by α-diversity positively affected by macrophyte height, and β-diversity affected by macrophyte height and composition, and water depth. Our results suggest environmental filtering as a major factor structuring frog assemblages even in relatively small and regionally rare ecosystems. These findings are highly relevant to ecology and conservation because they suggest that aquatic macrophyte banks should be considered as distinct biogeographic units from adjacent habitats.
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2
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FRANCESCA NICOLE ANGIOLANI LARREA
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INTERNAL MORPHOLOGY REVEALS REPRODUCTIVE ISOLATION BETWEEN TWO AMPHISBAENIAN CLOSELY RELATED SPECIES (SQUAMATA: AMPHISBAENIDAE)
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Advisor : SIRIA LISANDRA DE BARCELOS RIBEIRO
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COMMITTEE MEMBERS :
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CLAUDIA KOCH
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RICARDO ALEXANDRE KAWASHITA RIBEIRO
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SAMUEL CAMPOS GOMIDES
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SIRIA LISANDRA DE BARCELOS RIBEIRO
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Data: Feb 5, 2020
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Show Abstract
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Comparing reproductive tract morphology between closely related species may reveal mechanisms and processes of reproductive isolation mainly associated to evolutionary divergence. Although the reproductive tract of amphisbaenians has been qualitatively described for some species, interspecific variation associated with mechanical reproductive isolation has been poorly investigated through clearly defined hypotheses. Interspecific differences in reproductive tract may be particularly interesting in amphisbaenians, because fossoriality has caused bilateral asymmetry in internal organs. In this study we compared reproductive tract morphology between two closely related Amphisbaenidae species (Amphisbaena anaemariae and A. silvestrii). We used multivariate approaches to test the general hypothesis that interspecific divergences in nine variables that quantify the reproductive tract explain mechanisms and processes of reproductive isolation associated with evolutionary divergence. Our hypothesis testing was focused on investigating levels of sex-dependence and bilateral asymmetry on interspecific reproductive divergence. We found bilateral asymmetry in most of the variables measured, and sex-dependent morphology of the reproductive tract in both sexes, despite this finding was less evident in females. Our results are mainly associated with a combination of evolutionary forces acting on bilateral asymmetry and sex-dependent dispersal. Ultimately, this study provides insights into evolutionary processes based on reproductive isolation mechanisms in organisms for which sampling is hindered by fossoriality.
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3
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MARISE HELEN VALE DE OLIVEIRA
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Não informado.
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Advisor : THAIS ELIAS ALMEIDA
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COMMITTEE MEMBERS :
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Alexandre Salino
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GUSTAVO HERINGER
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RAFAELA CAMPOSTRINI FORZZA
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THAIS ELIAS ALMEIDA
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Data: Feb 17, 2020
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Show Abstract
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Ferns and lycophytes are seedless plants of ancient origin. Its dispersion through spores occurs by the wind, which makes them possible to occur in several places. They are important environmental indicators, becoming a special group when it comes to conservation. The Lower Tapajós region, located in the western region of Pará state, in the Tapajós River basin, has a large diversity of ferns and lycophytes, but all this richness is under threat from constant human actions such as fires in Protected Areas and construction of dams in the Tapajós river . The objective of this work was to analyze collection gaps, sampling biases, richness distribution and assess if protected areas in the Lower Tapajós are contributing to the conservation of the flora using ferns and lycophytes as model group. For this, a database was built from information of each fern and lycophyte specimen collected in the region and deposited in scientific collections or available in published works. These records were verified for location accuracy and correctness and were georeferenced when necessary. The records were checked and identified using a dichotomous key. The relationship between sampling effort and species richness was evaluated as well as whether records were biased towards areas close to access routes (defined as roads or navigable rivers). A comparison of species composition was made between the study areas and sixteen other areas that have fern and lycophyte inventories in the Brazilian Amazon. Here we present the first checklist for the ferns of the Baixo Tapajós basin, as well as for the four Conservation Units that presented records of these plants. It was possible to identify the conservation status of the species as well as places that had collection gaps. The sampling bias was also verified from the access routes in rivers and roads and it was possible to verify a collection density restricted to areas with easy access and close to large municipalities. Because it is a target region of destructive actions and a study group so sensitive to environmental changes, the information obtained from the research is of paramount importance to aid in the conservation of the flora of the Lower Tapajós region. Obtaining this data from an herbarium collection further enhances the preciousness of these scientific collections, and how much it is capable of storing and recording the history of the flora of a given region. Based on this study on information about the distribution of these plants, it is possible for managers of protected areas to use this information to develop species protection policies, so as to minimize conflicts of devastation in forest areas caused by human action.
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4
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ERIKA DOS SANTOS SOUZA
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Short- and long-term effects of fire and fire-induced vegetation cover on four lizard species in Amazonian savannas
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Advisor : RICARDO ALEXANDRE KAWASHITA RIBEIRO
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COMMITTEE MEMBERS :
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LAURIE J. VITT
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ROBSON WALDEMAR AVILA
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RODRIGO FERREIRA FADINI
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SAMUEL CAMPOS GOMIDES
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Data: Feb 27, 2020
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Show Abstract
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Ecological succession in tropical savannas is limited by seasonally predictable, but irregular fire, which consequently causes temporal variation in the habitat quality for the fauna. Although fire may cause negligible or positive effects on animals occupying savannas, most short-term studies are based on a single temporal sampling snapshot, and long-term studies are rare. In this study, we sampled four lizard species in Amazonian savannas to test the effects of fire and fire-mediated vegetation cover on lizard densities at two temporal scales. In the short term, we use three sampling snapshots to test the effects of fire and vegetation cover on estimated lizard densities over the subsequent 1–5 years. In the long term, we test the cumulative effects of fire and changes in vegetation cover over 21 years on current lizard density differences. In the short term, we found some significant effects of fire and vegetation cover on lizard densities, usually consistent with foraging and thermoregulation modes. However, results varied widely among species and years, suggesting that fire-mediated ecological relationships depend on unknown, highly dynamic variables over time. In the long-term, the most significant effects of fire and vegetation cover show that variation in habitat quality may change density spatial structure, which does not necessarily imply temporal changes in lizard densities. Fire is a natural feature of savannas and appears to have little impact on the resident lizards.
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5
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DAIANE BATISTA RODRIGUES
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Não obrigatório.
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Advisor : AMANDA FREDERICO MORTATI
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COMMITTEE MEMBERS :
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RODRIGO FERREIRA FADINI
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ADELAINE MICHELA E SILVA FIGUEIRA
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DAVIA MARCIANA TALGATTI
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Data: Feb 28, 2020
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Show Abstract
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We conducted an inventory of the fern, lycophyte and non-palm monocotyledon ground-herbs of terra firme riparian forests in the lower Tapajós River basin of the Brazilian Amazon. Eight 1.5 x 250 m plots, totaling 0.3 hectares, were surveyed along the watersheds of the Cupari and Curuá-Una tributaries of the Tapajós River, Floresta Nacional do Tapajós, Para, Brazil. To characterize the ground-herb community, we calculated species richness, abundance and Fisher’s alpha for each plot. To analyze floristic dissimilarity, we calculated the Bray-Curtis distance. In total, we sampled 3,130 individuals, 58 species, 27 genera and 20 families of riparian ground- herbs. Marantaceae (14 spp) was the richest family and Poaceae the most abundant family (738 individuals). The fern Triplophyllum glabrum (Tectariaceae) was the most frequent species, observed in 87.5 % of plots. Plots that showed the highest values for richness and species diversity were located in the Cupari River basin. The ground-herb community composition observed in the riparian zone here resembles that of other non-riparian forested sites in the Amazon with the plant families Marantaceae, Pteridaceae and Poaceae generally being the most commonly represented in the Amazonian ground-herb stratum.
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6
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TÁSSIO ALVES COÊLHO
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Anuran amphibian hemoparasites from eastern Amazonia
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Advisor : RICARDO ALEXANDRE KAWASHITA RIBEIRO
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COMMITTEE MEMBERS :
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RICARDO ALEXANDRE KAWASHITA RIBEIRO
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DRAUSIO HONORIO MORAIS
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LÚCIO ANDRÉ VIANA DIAS
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ROBSON WALDEMAR AVILA
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Data: Mar 31, 2020
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Show Abstract
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This study aimed to describe the first record of Trypanosoma sp. in Rhinella major as a new host and to analyze the relationship between hemoparasites and hematological and biochemical parameters of anuran amphibians collected in the eastern Amazon. Two chapters were produced for the present study. In the first chapter, 44 specimens of Rhinella major were captured in the area of influence of the Curua-una hydroelectric plant, in Santarém, west of Pará. Trypanosoma sp. with only one morphotype found. The prevalence, average intensity and average abundance rates were relatively low when compared with similar studies. In this study, we identified R. major as a new vertebrate host for Trypanosoma sp. in Brazil. In the second chapter, 32 specimens of Leptodactylus macrosternum and 20 specimens of Rhinella major were captured from anthropized environments in the western state of Pará, Brazil. After looking for and quantified hemoparasites under a light microscope, statistical tests were carried out in order to verify relationships between the abundance of parasites found and changes in the hematological and biochemical parameters analyzed. The analyzes revealed high rates of parasitic prevalence, with a record of mixed infections, with the presence of up to three hemoparasites (Trypanosoma sp., Hepatozoon sp. And microfilariae). Mann-Whitney tests did not reveal differences between the parameters analyzed. It was possible to detect correlations between Trypanosoma sp. and hematocrit and Hepatozoon sp. with glucose levels. Linear regression revealed that there is a significant negative relationship (p <0.05) for hemoparasites Trypanosoma sp. and Hepatozoon sp. with hematocrit levels.
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7
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JULIANA GONÇALVES CORRÊA
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Beta diversity of Sphaenorhynchini in South America and natural history of Sphaenorhynchus carneus (Anura, Hylidae) in Brazilian Amazon
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Advisor : RICARDO ALEXANDRE KAWASHITA RIBEIRO
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COMMITTEE MEMBERS :
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RICARDO ALEXANDRE KAWASHITA RIBEIRO
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KATYUSCIA DE ARAUJO VIEIRA
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THAÍS BARRETO GUEDES
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VANESSA KRUTH VERDADE
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Data: Oct 29, 2020
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Show Abstract
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Amphibian diversity can be influenced by many factors and quantifying the variation in biodiversity over time or space is a challenge. Beta diversity estimates are very useful for this purpose, as they quantify differences in species composition, functional or phylogenetic traits among multiple communities located in distinct portions of geographic and environmental gradients. However, beta diversity results may vary according to the variables used, but all available methods tend towards the general objective of identifying ecological, biogeographic and evolutionary factors that affect the variation in the composition of biodiversity across environments. Here, we investigate the factors that affect biodiversity in South America. For that, we selected the Sphaenorhynchini tribe, because it seems to be an ideal representative because it occurs in very different plant formations in relation to climate and vegetation, and some species seem to have been historically isolated by biogeographic barriers, such as large rivers and the expansion of the Brazilian Cerrado. Our main objective was to quantify the effects of evolutionary (phylogenies), historical (rivers as barriers) and ecological (geographical distance, environmental gradients) processes that have affected beta diversity in South America. Our results indicate that both taxonomic and beta diversity Phylogenetics of Sphaenorhynchini revealed two distinct clusters, corresponding to the Amazon and Atlantic Forest. In the Amazon, the effects of phylogenetic diversity were stronger than in the Atlantic Forest, which demonstrates that evolutionary processes have played a greater role in determining regional communities. In the Atlantic Forest, environmental variation seems more important. In both biomes, beta diversity was affected by environmental gradients, while in Amazon precipitation was the most important variable, tree cover was more relevant in the Atlantic Forest.
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8
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LOURIVAL BAIA DE VASCONCELOS NETO
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Preenchimento não obrigatório para qualificação
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Advisor : ALFREDO PEDROSO DOS SANTOS JUNIOR
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COMMITTEE MEMBERS :
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ALFREDO PEDROSO DOS SANTOS JUNIOR
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FABRICIO BEGGIATO BACCARO
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LEONARDO BARROS RIBEIRO
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SAMUEL CAMPOS GOMIDES
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Data: Dec 2, 2020
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Show Abstract
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The spatial distribution of organisms may be directly and indirectly affected by multiple environmental gradients. Environmental heterogeneity often causes variation in local habitat quality and levels of competition, which may lead to environmental filtering changing population density over a species geographic range. In this study we test the generalized hypothesis that savannas in Amazonia may contain enough environmental heterogeneity that lizard density estimates are not homogeneous across space. We sampled 26 plots, each of which covering 1500 m 2 (250m long, 6 m wide), to test the influence of air temperature, altitude, number of termite mounds, shrub cover, canopy openness, competitor density, and interactions between some of these gradients on Cnemidophorus cryptus (Squamata, Teiidae) density. We found positive effects of number of termite mounds and shrub cover on C. cryptus densities. These findings suggest that high availability of refuge sites from the high temperatures (up to 40 ºC) experienced by midday savannas favor high densities. Additionally, we found negative effects of altitude and temperature on the estimated densities, which suggests environmental filtering at thermally unsuitable sites. However, an interaction plot showed that altitude effects on C. cryptus density are only significant under low temperatures. Overall, our findings suggest that C. cryptus does not homogeneously occupy available habitats, but environmental filtering may emerge from lack of shelter and inefficient thermoregulation toward body heat loss at relatively low altitudes (< 104 m), and heat gain at relatively high temperatures (> 104 m).
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9
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DARLEM NIKERLLY AMARAL PAIVA
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Preenchimento não obrigatório para qualificação.
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Advisor : THAIS ELIAS ALMEIDA
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COMMITTEE MEMBERS :
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THAIS ELIAS ALMEIDA
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THIAGO JOSE DE CARVALHO ANDRE
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BÁRBARA SIMÕES SANTOS LEAL
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ANDRÉ LUIS DE GASPER
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Data: Dec 21, 2020
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Show Abstract
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The combination of techniques capable of discriminating plant species that are difficult to circumscribe is essential to the proper understanding of biodiversity. The genus Microgramma C.Presl (Polypodiaceae), for example, due to the great complexity of forms associated with the wide area of occurrence, becomes a group highly suggestive to the taxonomic investigation. Thus, we aim to propose processes of discrimination in species of neotropical ferns through integrative tools of great interest in the taxonomic field. We used near-infrared spectroscopy (FT-NIR) in thirteen species (M. baldwinii, M. crispata, M. dictyophylla, M. geminata, M. lindbergii, M. lycopodioides, M. megalophylla, M. percussa, M. persicariifolia, M. reptans, M. squamulosa, M. thurnii, and M. vacciniifolia) and morphometric analysis with four species (M. crispata, M. geminata, M. mauritiana, and M. vacciniifolia). These are important methods for the discrimination of botanical species in association with multivariate analyzes, such as Discriminant Analysis, cross-validations, Canonical Discriminant Analysis (CDA), and Cluster Analysis (CA). Based on multivariate analyzes, the morphometric technique supported the existence of all previously recognized taxa, as well as the Near-Infrared Spectroscopy (FT-NIR), with which we recovered more than 95% of correct prediction. Both applied techniques demonstrated a high potential for discrimination between the proposed species, demonstrating that the use of different approaches can favor greater reliability in the delimitation between controversial groups.
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