Navegando por Orientadores "GIARRIZZO, Tommaso"

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Acesso aberto (Open Access)
Distribuição espaço-temporal da ictiofauna de poças de maré de um estuário amazônico: interação de fatores
(Universidade Federal do Pará, 2012-02-28) OLIVEIRA, Rory Romero de Sena; GIARRIZZO, Tommaso; http://lattes.cnpq.br/5889416127858884
The intertidal rockpool ichthyofauna has been studied for several years in temperate and tropical regions at the Pacific Coast, however, in Brazil, the knowledge about it is still incipient. The aim of the present study was to investigate the fish assemblages in tidepools located in three different habitats: rocky outcrop, mangrove forest and salt marsh, at Areuá Island, Curuçá river estuary, North Brazil. Samples were taken quarterly from February 2009 to November 2009, during the spring tide, following a standardized methodology. The physicochemical parameters changed along a topographic gradient and were responsible for the spatio-temporal distribution of fish fauna at rocky outcrop tidepools. Salinty, mean depth and substrate heterogeneity were the parameters that more explained the variations in fish fauna distribution A clear segregation of fish assemblages was found between the tidepools of rocky outcrop and vegetated habitats (tideools in mangrove forest and saltmarsh). These findings suggest that the fish fauna has preferences for some habitats influenced by environmental variables and substrate heterogeneity. However, more researches should be conducted taking into account inter-and intra-specific relationships.
Acesso aberto (Open Access)
Explorando a biodiversidade do rio Xingu: apresentação e validação de um novo equipamento de amostragem de DNA ambiental
(Universidade Federal do Pará, 2024-04-29) BAHIANA, Bruno Gonçalves; KEPPELER, Friedrich Wolfgang; GIARRIZZO, Tommaso; http://lattes.cnpq.br/5889416127858884
Knowledge and monitoring of biodiversity are key elements for defining actions and initiatives focused on nature conservation and restoration. However, monitoring techniques are generally expensive and time-consuming, which complicates efforts to identify and manage biological diversity. In this sense, it is essential to investigate new fast, non-invasive and low-cost methods that can provide reliable and robust results and information, highlighting, in this context, approaches based on the use of environmental DNA (eDNA). eDNA is a complex mixture of genetic material originating from entire organisms or parts of them, present in environmental matrices, which can be, for example, soil, water or sediment. This project presents a prototype of a simple and low-cost equipment to obtain eDNA sampling, aiming to explore the richness and composition of the ichthyofauna in the Fish Transposition System of the Belo Monte Hydroelectric Power Plant (HPP), located in the middle course of the Xingu River, a hyperdiverse river located in the Amazon Brazilian. To this end, a new and affordable piece of equipment was manufactured for passive collection of genetic material (eDNA) using a metal structure and two PVC tubes. A flow meter was attached to one of the tubes and two rolls of gauze were firmly attached to the other tube. From the samples, which were collected every two hours over a 24-hour period, a species inventory was generated using a combination of fish-specific molecular markers (Tele02 12S). To validate the equipment and the proposed methodology, the temporal variation in the richness and composition of the fish fauna detected with eDNA were compared with those recorded during monitoring using the Video-Image System located at the exit of the STP. The results indicate that the method was efficient and sampled 100% of the ichthyofauna orders that were recorded in monitoring with SVI, but the similarity between the two methods reduced as taxonomic specificity increased. This result can be explained by the low representation of Xingu species in existing genomic libraries. In this sense, eDNA is a promising approach with great potential to become a valuable tool for studying and monitoring the composition of fish in highly diverse tropical freshwater rivers with affordable costs and minimal impacts on organisms and habitats, but which, in this At the moment, more basic research is needed so that it can replace and/or complement traditional sampling methods.
Acesso aberto (Open Access)
Revisão taxonômica de Tometes Valenciennes, 1850 (Characiformes: Serrasalmidae) das drenagens do Escudo das Guianas
(Universidade Federal do Pará, 2013-02-21) ANDRADE, Marcelo Costa; JÉGU, Michel Louis Arthur Marie Ange François; http://lattes.cnpq.br/1270768412397418; GIARRIZZO, Tommaso; http://lattes.cnpq.br/5889416127858884
The genus Tometes Valenciennes, 1850 was originally described for the typespecies T. trilobatus, by presenting incisiform and bi- tricuspid teeth. However, the genus was synonymized with Myleus Müller and Troschell, 1844 for approximately a century and a half until being revalidated with an addition of two new species descriptions, T. lebaili and T. makue. This study presents a taxonomic review of Tometes from Guyana Shield where the three nominal species are recognized as valid and here were re-described, also a new species from Trombetas basin was described, increasing the diversity and distribution of genus. Among the main characteristics of diagnosis were observed: T. trilobatus is distinguishes from its congeners by having dentary and premaxillary teeth with the central cusp with rounded edge (vs. teeth with the central cusp or principal cusp with sharp edge). T. lebaili differs from others Tometes by having mouth oblique dorsally directed (vs. terminal mouth). T. makue is different by having a few spines on the serrae prepelvic, always between 0 and 9 spines (vs. over 9 spines). Already the new species is distinguished by the neurocranium with a slight concavity at the level of the epiphyseal bar, and also by having scales of irregular size (vs. dorsal profile of the neurocranium without a slight concavity, and scales of regular size). All species of Tometes are strictly rheophilic, and occur exclusively in the rapids of shield rivers, complex and fragile biotopes that are threatened by anthropogenic activities. The conclusions reached by this study highlight the urgent challenge to understand more fully existing species/habitat relationships.
Acesso aberto (Open Access)
Segregação espaço-temporal das assembléias de peixes em ambientes de entremaré não vegetado e canal subtidal de um estuário de macromaré no norte do Brasil
(Universidade Federal do Pará, 2012-02-28) LOUREIRO, Sarita Nunes; GIARRIZZO, Tommaso; http://lattes.cnpq.br/5889416127858884
Various estuarine environments are hydrologically and ecologically connected and provide vital functions to several aquatic organisms. Spatial and temporal segregation were observed in fish assemblages structure (average biomass) in the subtidal channel and intertidal nonvegetated environments in the estuary of the Marapanim River, North Brazil. Monthly fish sampling were carried out between August 2006 and July 2007 at the subtidal channel and intertidal non-vegetated environments using a beam trawl and beach seine, respectively. A total of 41,496 individuals belonging to 29 families and 76 species was collected. Species richness in the subtidal channel (71 species) was higher than in the intertidal non-vegetated environments (51 species). Different associations in the composition of the species and functional guilds were observed between the subtidal channel and the intertidal non-vegetated environments, through the Detrended Correspondence Analysis. Significant differences in fish fauna composition were found between environments, seasons and zones, through Analysis of similarities (ANOSIM). The fine sediments (silt-clay), sand and salinity were the most important factors structuring the fish assemblages. In summary, these results can be associated to the fish tolerance to environmental factors, and to different feeding type.
Acesso aberto (Open Access)
Uso dos recursos alimentares por populações quilombolas da Amazônia brasileira
(Universidade Federal do Pará, 2012-08-31) MELO, Luciana Santos de; GIARRIZZO, Tommaso; http://lattes.cnpq.br/5889416127858884
This work verified the extrativism activities and the consumption of animal protein of four Quilombola communities from the protected area Reserva Biológica do rio Trombetas, Pará state, Brasil. The data were obtained by forms in a participative methodology after the food were weigthened in a 5kg balance. The data were colected weekly through 12 months (August 2007 to July 2008). The Cachoeira Porteira community shown the samllest average of fishies consumption (371,6g ± 312,3g. capita-1.day-1) and Lago Mussurá showed the higger value (567,5g ± 415,5g. capita-1.day-1). The Lago Erepecu show the higger average of hunting (276g ± 407,7g.capita-1.day-1). Chelonian eggs were the one iten that show significant differences bettwen sazonallity periods (seca and vazante). This search confirmed that fishing resources was the most abundant bettwen all the itens, followed by hunting. The industrial protein food suplies don´t play important role in the dietary activities in the four communities studied.