Dissertações em Ecologia (Mestrado) - PPGECO/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/8938

O Mestrado Acadêmico foi criado em 2015 e pertence ao Programa de Pós-Graduação em Ecologia (PPGECO) do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA) em parceria com a Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA).

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Agora exibindo 1 - 9 de 9

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Ecologia populacional de Clibanarius symmetricus (Anomura: Diogenidae) em uma praia exposta da Costa Amazônica Brasileira
(Universidade Federal do Pará, 2017-06) DANIN, Ana Paula Ferreira; SANTOS, Cleverson Ranieri; PETRACCO, Marcelo; http://lattes.cnpq.br/6834814201680920; https://orcid.org/0000-0001-6501-0099
The hermit crab Clibanarius symmetricus has a wide geographical distribution along the Western Atlantic where is a conspicuous species in intertidal and shallow waters of several ecosystems as sandy beaches, tidal flats, mangroves and rocky shores. However, information on the life history traits of this species is in general limited to the subtropical regions. Here, we access the population structure and dynamics, and the shell occupation pattern of a C. symmetricus population inhabiting a rocky outcroup of an exposed sandy beach on the Amazon coast. For this purpose, monthly samplings were carried out from October 2015 to September 2016. Higher density of C. symmetricus occurred in the drier season and the frequent presence of ovigerous females suggests continuous reproduction. The overall sex-ratio was skewed toward females (0.6:1, M:F) and sexual dimorphism was recorded. Males and females had similar curvature, but smaller growth performance index than others subtropical populations. The turnover rate (P/B) was also similar between sexes as a consequence of similar growth constant. Thaisella coronata was the most occupied (97.1%) gastropod shell and the overlap in shell utilization by hermit crabs of same size may reflect competitive interactions. Also, some difference in occupation between sexes was documented, suggesting that males can occupy larger and more suitable shells.
Acesso aberto (Open Access)
Efeito da perda de cobertura florestal sobre a diversidade de peixes de riachos em uma zona de transição Cerrado-Amazônia
(Universidade Federal do Pará, 2019-02-28) FREITAS, Pâmela Virgolino; JIQUIRIÇÁ, Paulo Ricardo Ilha; http://lattes.cnpq.br/3392388693636935; SILVA, Karina Dias da; http://lattes.cnpq.br/2271768102150398
Currently, the expansion of the agricultural frontier in the Amazon represents a profound change in the world’s vegetation cover. This expansion causes decrease of forest cover, affecting the environmental integrity of streams, as well as the richness of associated communities. We aimed to evaluate the effects of loss of forest cover on the physical integrity of streams, and on the taxonomic and functional diversity of fish assemblages in a Cerrado-Amazon transitional zone. We sampled nine streams in the Alto Xingu river basin. The streams possess microbasins covered by different percentages of transitional Cerrado-Amazon forest and croplands. We did not detect the effect of loss of forest cover on the physical integrity of streams, and neither on fish taxonomic diversity. However, we found a negative effect on the functional diversity. The physical integrity of streams was not associated with taxonomic and functional diversity of fish assemblages. The conversion of forest areas to croplands, on the riparian zone, affects negatively the functional richness of fish assemblages, acting as an environmental filter, leading to the disappearance of species that could have performed important ecosystem functions. Furthermore, the establishment of restoring and conservation strategies of areas affected by deforestation must be a priority on all streams drainage systems, especially on the riparian zone scale, to minimize impacts on species. To understand which factors can better structure fish assemblages in streams, it is necessary to do research, that can give basis to formulate strategies for the preservation of those organisms.
Acesso aberto (Open Access)
Efeitos de atividades de subsistência de ribeirinhos sobre a heterogeneidade ambiental e a diversidade de insetos aquáticos em diferentes níveis espaciais de riachos amazônicos
(Universidade Federal do Pará, 2021-09) COSENZA, Jorge Felipe Abreu; FARIA, Ana Paula Justino de; http://lattes.cnpq.br/6041546003155327; https://orcid.org/0000-0003-2729-5358; SANTOS, Raphael Ligeiro Barroso; http://lattes.cnpq.br/7227882802366966; https://orcid.org/0000-0001-9717-5461
The deleterious effects of large-scale impact activities such as agriculture, intensive ranching, dam construction and mining on Amazonian biodiversity have been constantly studied. On the other hand, the effects of smaller-scale impact activities are neglected. An example is the activities practiced by traditional populations, such as riverside populations, who have lived for generations on the banks of rivers and streams in the Amazon basin. There are still few studies that evaluate the effects of anthropic activities considered to have less impact on the diversity patterns of aquatic insects at different spatial scales using taxonomic and functional approaches concurrently. Thus, we evaluated how subsistence activities practiced by riverside populations affect the taxonomic and functional alpha and beta diversity of aquatic insects of the orders Ephemeroptera, Plecoptera and Trichoptera - (EPT), at different spatial levels (between sampling units within streams and between streams). We tested the hypotheses that (H1) the altered streams have less environmental heterogeneity among themselves and the composition of environmental characteristics different from the control streams; (H2) altered streams have lower alpha taxonomic and functional diversity than control streams; (H3) the taxonomic and functional beta diversity between sampling units and between altered streams is lower than between sampling units and control streams; (H4) the beta diversity observed between sampling units and between altered streams is generated primarily by richness difference, while between sampling units and control streams, the replacement of species/functional groups predominates. We conclude that the disturbance caused by the riverside populations subsistence activities, specially navigation, altered the characteristics of the habitats and, in certain aspects, the EPT assemblages of the streams of the Caxiuanã region. Beta diversity patterns did not change, but there was a loss and increase in abundance of some genera as a result of the changes. Thus, the maintenance of beta diversity is not necessarily a sign of high diversity and ecological integrity, as the increased variation in the composition of these assemblages may be a result of the loss of sensitive species and the increase of more generalist species. The functional approach responded similarly to the taxonomic one in all environments and spatial levels, which suggests that this effect is dependent on the biological group analyzed and on the type and intensity of change in the environment. The activities practiced by the riverside populations altered the local community of aquatic insects in a less impactful way compared to other activities commonly practiced in the Amazon, such as logging, agriculture, palm plantation, grazing and mining. To reduce a possible loss of species in the streams in the region, it is necessary to maintain the natural conditions of the habitats, such as a high density of vegetation cover on the banks, a large number of leaf banks in the riverbed and a high frequency of slow flows.
Acesso aberto (Open Access)
Efeitos de perturbações antrópicas sobre os fatores ambientais e espaciais na estruturação de metacomunidades de insetos aquáticos na Amazônia Oriental
(Universidade Federal do Pará, 2022-07) OLIVEIRA, Stéfany Vitória Santos; FARIA, Ana Paula Justino de; http://lattes.cnpq.br/6041546003155327; https://orcid.org/0000-0003-2729-5358; SANTOS, Raphael Ligeiro Barroso; http://lattes.cnpq.br/7227882802366966; https://orcid.org/0000-0001-9717-5461
Anthropogenic pressures resulting from changes in land use have great potential to impact the dynamics of aquatic insect metacommunities, once they alter the environmental quality of streams, and may impose barriers to dispersal. The objective of this study is to evaluate the structuring of aquatic insect assemblages (Ephemeroptera, Plecoptera and Trichoptera orders - EPT) in Amazonian streams under natural conditions (control streams) and under disturbance by human activities (altered streams) is influenced by characteristics of fluvial habitats and by the spatial structure. Our hypotheses is that in control streams, habitat characteristics are the main structuring factor of EPT assemblages, and that in altered streams, habitat characteristics related to human disturbances and spatial structure are the main assemblage structuring factors. A total of 74 streams were sampled in the Capim River basin, Pará, Brazil, wich 38 are control streams and 36 are altered streams. In each of them, environmental variables associated with water chemistry, channel hydromorphology, sediment types, riparian vegetation and insect shelter were measured, in addition to the proportion of land uses and EPT assemblages. Our results showed that several environmental characteristics of the streams were affected by human activities. Environmental factors had a greater influence on the structuring of EPT assemblages than the other factors evaluated, both in the control and altered streams. The influence of the spatial factor was weak. The assemblages of altered streams were structured both by environmental variables affected by disturbances and by variables subject to natural variation, demonstrating that the assemblages in these environments are not governed only by environmental changes. Our study demonstrates the importance of the species sorting process in metacommunities of Amazonian streams, and the role of disturbance in this process.
Acesso aberto (Open Access)
Efeitos do manejo do açaí (Euterpe oleracea Mart.) sobre a avifauna em florestas de várzea estuarina na Amazônia
(Universidade Federal do Pará, 2017-05-30) NUNES, Raphael de Vasconcelos; LEES, Alexander Charles; http://lattes.cnpq.br/8887958109144699; LOPES, Maria Aparecida; http://lattes.cnpq.br/3377799793942627
Human actions and use of natural resources, by removing plant species, food resources or altering the environment’s structure, may have indirect effects on animal communities. The expansion of açaí (Euterpe oleracea) production has been altering floodplain forests through its management actions, resulting in environmental degradation and even substitution of forest for plantation areas, thus causing floristic empoverishment. In this paper we investigate the effects of this species management on the structure of bird community in an insular system of the Amazon River delta. Our hypothesis was that we would find less bird species diversity on managed areas (low and high intensity management) compared to non-managed forest fragments due to the environmental degradation caused by this practice. To assess the diversity and abundance of bird species we conducted point counts with auditory recordings and observations in three sites per treatment. We found a decrease tendency in bird species richness in intensively managed areas; but didn’t detect any changes on bird abundance and diversity in areas managed for açaí fruit production. We found alterations on bird community composition, being this more homogenous in managed areas. The effects of açaí management upon the fauna are still hard to detect but may arise in the future and our results point to the homogenization and species loss in areas subjected to intense management, causing birdlife empoverishment.
Acesso aberto (Open Access)
Fatores determinantes do uso de habitats por mamíferos ungulados (Artiodactyla e Perissodactyla) na Amazônia Oriental
(Universidade Federal do Pará, 2022-04) ALVES, Michel Jacoby Pereira; OLIVEIRA, Ana Cristina Mendes de; http://lattes.cnpq.br/1199691414821581; https://orcid.org/0000-0002-7863-9678
Land use by human activities in landscapes of the eastern Amazon has been modifying and suppressing the native habitats of this region, altering the dynamics of ecosystems and negatively affecting biodiversity. Herbivorous-frugivorous ungulate mammals are among the groups of mammals most affected by these changes in ecosystems. Through the use of camera traps, we recorded ungulates and measured hunting pressure. Using satellite images, we evaluated the environmental characteristics and human pressures that may be influencing the abundance of tapirs (Tapirus terrestris), deer (Mazama americana and Mazama nemorivaga) and wild pigs (Pecari tajacu and Tayassu pecari) in habitats with different levels of disturbance. The species showed different responses to landscape and land use variables. Our result demonstrates that all species studied showed some degree of tolerance to disturbed habitats, except for abandoned pasture and oil palm plantation habitats. We also demonstrate that although the species use degraded habitats, they have a high dependence on forested habitats.
Acesso aberto (Open Access)
A heterogeneidade de bancos de macrófitas aquáticas e a diversidade de peixes em uma ria fluvial amazônica
(Universidade Federal do Pará, 2019-03) NONATO, Flávia Alessandra da Silva; MONTAG, Luciano Fogaça de Assis; http://lattes.cnpq.br/4936237097107099; https://orcid.org/0000-0001-9370-6747; MICHELAN, Thaísa Sala; http://lattes.cnpq.br/4609629132683283; https://orcid.org/0000-0001-9416-0758
In freshwater ecosystems, macrophyte species can provide habitat heterogeneity with different structural forms, ranging from free submerged species to rooted species, which serve as a substrate for spawning, food and refuge against predation to fish and other organism. In the 49 present work we tested the effect of the heterogeneity of aquatic macrophyte banks on the richness and abundance and functional traits of the fish in flooded rivers of the Amazon. To investigate the relationship between the heterogeneity of the macrophyte banks and the richness, abundance, and functional characteristics of the fish, we used them CWM analysis and simple linear regressions. We identified 16 species of aquatic macrophytes and 21 species of fish in the 34 sampling points. The macrophyte banks were dominated by the species Eichhornia azurea and. E. crassipes. The most abundant fish species were Hemigrammus ocellifer and Laimosemion strigatus. The linear regression result was only significant between the heterogeneity of the macrophyte banks on two functional attributes, both linked to the locomotion of the fish. Our results show that the association between the heterogeneity provided by the macrophyte banks is an environmental filter for fish species that have high maneuverability, since these species can swim between macrophyte structures. Thus, we can observe that the heterogeneity provided by aquatic macrophytes, although not affecting the richness and abundance of fish, is important for different species of fish, but for those that use and depend on these banks as a refuge.
Acesso aberto (Open Access)
Influência da perturbação ambiental na assembleia de pequenos mamíferos nãovoadores na Amazônia Oriental
(Universidade Federal do Pará, 2019-06) SOTOMAYOR, Omar Santiago Erazo; OLIVEIRA, Ana Cristina Mendes de; http://lattes.cnpq.br/1199691414821581; https://orcid.org/0000-0002-7863-9678
Anthropogenic environmental disturbance results in different structural modifications of the forest, which can lead to changes in species composition patterns, taxonomic and functional diversity. We evaluated the influence of environmental disturbance on the structure and diversity of assemblies of non-flying small mammals in the eastern Amazon. We analyzed species composition, richness and abundance and their functional characters as assemblage descriptors, considering their environmental variations, in three levels of environmental disturbance: (i) forest interior; (ii) edge of the forest; and (iii) rural space. The diversity α (taxonomic and functional) remained relatively constant through the levels of anthropogenic environmental disturbance. However, in the taxonomic diversity β, the assemblage of the forest-edge community presents abundance gradients, where they share most of their species, but some individuals of the edge are lost in the forest. On the other hand, the rural forest and rural edge assemblages present a balanced variation of abundance, in which individuals of some species of forest and border areas are replaced by individuals of different species in rural space. Among the morphological attributes we observed subtler responses of the community, small mammals characterized by a larger tail predominate in forest areas and those characterized by a larger foot predominate in rural areas. We conclude that the morphological attributes (tail and foot length) are determining factors in the assemblage composition patterns of the small non-flying mammals and their habitat selection in environments facing anthropic impacts. The changes and patterns identified in our study are of crucial importance for biodiversity management and conservation plans.
Acesso aberto (Open Access)
Variação temporal de Ephemeroptera, Plecoptera e Trichoptera (EPT) com base em sua especificidade ambiental em riachos impactados pela mineração na Amazônia Oriental
(Universidade Federal do Pará, 2022-03) PÉREZ, Juan Mateo Rivera; JUEN, Leandro; http://lattes.cnpq.br/1369357248133029; https://orcid.org/0000-0002-6188-4386; FEITOZA, Yulie Shimano; http://lattes.cnpq.br/7380463661182614; https://orcid.org/0000-0003-2931-4719
Knowing aquatic diversity and understanding how different species are distributed in time and space has become one of the main focuses of research in ecology in recent decades. This is mainly due to the rapid environmental changes caused by human activities. In this scenario, aquatic insects of the orders Ephemeroptera, Plecoptera, and Trichoptera (EPT) are used to monitor environmental conditions because they are sensitive to these changes. The intensity of the response depends directly on the breadth of the niche of each taxon given the variability and changes in the habitat. With the general objective of investigating the effects of iron mining based on the environmental specificity of EPT in streams of the Carajás National Forest in Pará, over six years, this dissertation is divided into two chapters. In the first, we classified EPT taxa into generalists and specialists and evaluated whether the estimated abundance and richness of these groups vary according to the level of alteration of the streams impacted by mining activities. In the second, we evaluated the spatial and temporal variation of the beta diversity of generalist and specialist EPT. In both studies, EPT data sampled annually in 24 streams over six years were used in streams conserved and impacted by mining in the Carajás Flona. A total of 49,922 individuals distributed in 59 genera were collected, of which 31 were classified as specialists and 28 as habitat generalists. In the first chapter, we verified that there was a negative effect of mining on the estimated wealth and a positive effect on the abundance of specialist genera. On the other hand, the abundance and estimated wealth of generalists were negatively influenced by the mining effect. In the second chapter, no differences were found in gender composition or heterogeneity between treatments. However, over time, both generalists and specialists changed their composition. Mining affects the communities of EPT generalists and specialists, in particular, specialists from sites impacted by mining that showed an increase in their abundances, possibly due to the expansion of habitat made available by the process of habitat homogenization. For generalists, gender loss was the main component in temporal beta diversity, while specialists showed gender gains and losses. Therefore, mining has affected communities of both generalist and specialist groups over the years, despite their habitat specificity, presenting different patterns of environmental changes.

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