Mestrado em Ecologia e Evolução (ICB)

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No limiar tênue entre teoria e realidade, sazonalidade e caos em sistemas planctônicos
(Universidade Federal de Goiás, 2009-02-26) Ferreira, Heury Sousa; Marco Júnior, Paulo De; http://lattes.cnpq.br/2767494720646648; Marco Júnior, Paulo De; Diniz Filho, José Alexandre Felizola; Silva, Daniel Brito Candido da
The Chaos Theory is an alternative tool to stochastic dynamic modeling when target biological systems show irregular and no predictive behavior. The plankton is a model group of organisms to theoretical and experimental investigations in chaotic dynamics due to its intrinsic biological characteristics as small size, high reproductive rate and short life cycle, with the additional advantage of its public interest related to practical problems. In this work we investigated the dynamical aspects of a NutrientPhytoplankton-Zooplankton seasonal forced model, created by means of the addition of the Zooplankton level on a Nutrient-Phytoplankton seasonal forced model that show chaotic behavior, proposed by Huppert et al. (2005). An important outcome of the Huppert’s model is that the intensity of the seasonal forcing is the control parameter of the system. We investigated the zooplankton effect on the stability of the model, and the chaos control by means of pulses in the intensity of the seasonal forcing. Our results show that strong and weak seasonal forcing implicates in cyclical fluctuations of phytoplankton populations, and those cycles had higher amplitude in strong seasonal forcing. Between those two extremes, there is chaos. The zooplankton mortality is a fundamental component of the behavior of the model. In fact, despite of seasonal forcing values that can promote chaotic behavior, the model can show cyclic behavior to some values of mortality rates. This suggests that absence of top-down control in the models built to understand phytoplanktonic dynamics (blooms are only a consequence of this), result in an over-simplification and lack of conceptual comprehension of the system. Our results show that periodic pulses can be able to control the chaos on moderate seasonal forcing, and to promote chaos to weak and strong seasonal effects. The pulses are theoretical indicatives of how climatic changes influences a seasonal variable can to affect the dynamics aspects of planktonic systems.
Áreas prioritárias para restauração no estado de Goiás
(Universidade Federal de Goiás, 2020-07-03) Silva, Thalline Rodrigues da; Loyola, Rafael Dias; http://lattes.cnpq.br/7649189080736923; Loyola, Rafael Dias; Diniz Filho, José Alexandre Felizola; Brum, Fernanda Thiesen
In parallel with strategies and actions focused on the conservation of biodiversity, scientists, decisionmakers, and different sectors of our society have been developing on strategies focused on the restoration of degraded areas. This is a particularly important issue for Brazil as signatory to the Paris Agreement, in which the Brazilian government is committed to restoring 12 million hectares of degraded areas by 2030. Such restoration will be regionalized, and the states of Brazil will need to indicate their priorities, strategies and tools to accomplish such task. Here, we identified priority areas for restoration in the state of Goiás in order to build scenarios in which the retention of soil carbon stock is maximized, as well as the representation of plant species, while seeking the lowest cost of opportunity to perform this restoration on rural landowners. We ran prioritizations following the principles of systematic conservation planning. We also considered the environmental debt within rural properties and, based on that, we evaluated all types of agricultural culture found on the properties to generate opportunity costs associated with restoration. After analyzing 166,635 rural properties across the state, we found a total debt of approximately 1,682,804.1330 hectares within properties’ Legal Reserve. We also observed that most rural properties that should be restored have an opportunity cost below R$5,000. In all prioritization scenarios, areas to the east and northeast of the state of Goiás were considered as priority. Our best restoration scenario captured ~35% of the state's entire carbon stock, nearly 70% (on average) of the distribution of endangered plant species included in the study and a reduction in opportunity cost of more than 70%. Systematic planning for restoration, as proposed here, if carried out in an organized and accountable way, can maximize the connectivity of protected areas within rural properties, bringing greater protection of species and guarantee of the provision of ecosystem services.
Impacto das cinzas de queimadas no ambiente aquático e na comunidade fitoplanctônica
(Universidade Federal de Goiás, 2023-07-28) Jesus, Gabriel Sampaio de; Nabout, João Carlos; http://lattes.cnpq.br/3335844675689429; Bortolini, Jascieli Carla; http://lattes.cnpq.br/5475113165248615; Bortolini, Jascieli Carla; Carneiro, Fernanda Melo; Carvalho, Priscilla de
Among the main threats to biodiversity are anthropic fires, a joint event, especially during the dry period. However, studies on the indirect effects of fires on aquatic ecosystems are scarce. In this study, we investigated how water quality and phytoplankton community structure might be affected by ash from fires in the Brazilian Cerrado. We used a microcosm experiment to simulate the aquatic environment with different scenarios of ash concentrations, and we evaluated over time the abiotic conditions, composition, richness, and phytoplankton density. We detected an increase in total phosphorus ammoniacal nitrogen concentrations after ash insertion. Regarding the phytoplankton community, we identified changes in composition as a function of time, and we did not recognize changes in richness and density in response to treatment. Our results indicate that ash from fires in the terrestrial environment can affect water quality and the species composition of aquatic communities. However, we suggest longer-duration experiments to evaluate the phytoplankton community's delayed responses.
Communication breakdown! Como a perda de informação afeta o resultado de interações comportamentais em Sporophila maximiliani
(Universidade Federal de Goiás, 2023-07-14) Santos, Gabriela Sales dos; Nomura, Fausto; http://lattes.cnpq.br/9506582657045983; Nomura, Fausto; Azevedo, Cristiano Schetini de; Bastos, Rogério Pereira
Communication is part of several social interactions of animals and the transmission of information and decoding by the receiver depend on the quality of the emitted signal, which can be acoustic, visual and/or chemical. The degradation of these signals can generate loss of information and cause damage to the animals' vital processes. Considering that anxiety prepares the individual for unpredictable situations, the loss of information has the potential to cause stress and motivational conflict in organisms, resulting in altered behavior, as has already been demonstrated for anuran species. In this project, we seek to understand, through a systematic review, trends, advances and gaps in experimental studies on animal communication, with a focus on studies that investigate the effect of signal quality changes on communication and interactions. We also aimed to understand whether the loss of information alters behavioral interactions in birds, using the species Sporophila maximiliani as a model. For this, we performed two experiments: i) a playback experiment, to simulate the acoustic signal and ii) a mirror model, to simulate the visual signal. We identified that the number of publications on animal communication with an experimental approach, which investigate social interactions and/or behavioral changes, has been increasing since the 90s. However, the impact of these studies on the scientific community does not follow this growth, with few publications receiving greater attention. emphasis. We also note that the number of studies using endangered species is still low, showing a lack of studies with more vulnerable animals. There are also few experimental studies with signal quality in relation to the total number of publications in animal communication, despite the results of studies that address changes in the signal showing that damage to the signal has an impact on individuals and the interactions they carry out. In our experiments, we also identified that the behavior of Sporophila maximiliani is affected by the loss of information during communication, generating stress and fear in the individuals. However, this effect was dependent on the signal modality, so that for visual signals the loss of information does not cause this effect. Thus, changes in signals in communication had a direct effect on individuals and it is extremely important to promote studies that seek to understand how each group of organisms responds to these changes.
Avaliação do estado de conservação das aves brasileiras e da eficiência dos esforços conservacionistas através das listas vermelhas de espécies ameaçadas
(Universidade Federal de Goiás, 2014-03-26) Spindola, João Paulo da Silva; Silva, Daniel de Brito Candido da; http://lattes.cnpq.br/5139765780779893; Silva, Daniel de Brito Candido da; Oprea, Monik; Bianchi, Carlos Abs da Cruz
The Planet is going through a Biodiversity crisis, the current extinction rates may be up to 1000 times greater than the natural background rates. Because of this, international policies were signed, with the purpose to mitigate the loss of biodiversity. The Red List Index (RLI) is among the adopted indicators to evaluate the performance of conservation actions put into action by countries. The RLI is calculated using information of changes in the red lists categories to a set of species. This tool has been largely applied both at regional, and the global levels in order to make a systematic biodiversity monitoring. Here, we applied the RLI to native Brazilian birds in the time interval of 1988-2012. We have explored the trends in the RLI between different biomes, taxonomic orders and threats. Furthermore, we evaluated the National Actions Plans (PAN, in Portuguese) in order to assess their effectiveness through the RLI. We found out that despite conservation actions, the overall trend is an increased extinction risk. Between the biomes, the Amazon presents the greater decline in bird conservation status. The factor that caused the greatest increase in threat is the impact of road construction. The PAN uses an approach of reactive conservation, focusing on species already threatened. In the absence of conservation efforts the RLI to endemic species would have declined an additional of 12.95%.
Contribuição do gradiente longitudinal e dos tributários na estruturação da comunidade zooplanctônica nos reservatórios em cascata no rio Tocantins
(Universidade Federal de Goiás, 2022-08-30) Mendonça, Laura Beatriz Gomes; Carvalho, Priscilla de; http://lattes.cnpq.br/4723821511788681; Lopes, Vanessa Guimarães; Bortolini, Jascieli Carla; Carvalho, Priscilla de
Understanding the importance of the dispersion of planktonic organisms in the structure of communities has been one of the main goals of ecological studies in the stretches of rivers affected by the construction of reservoirs. Along a cascade of reservoir, the diversity of planktonic organisms located in the central body of a reservoir can be influenced both by the tributaries that flow into this reservoir and by the reservoirs upstream. In this way, the main goal of this study was to analyze the structure of the zooplankton community along a cascade of reservoirs in the Tocantins River and verifying the importance of tributaries and upstream reservoirs in the composition and abundance of species. We analyzed the richness and abundance of the zooplankton community in a stretch of the Tocantins River composed of three reservoirs built in cascade: HPP Cana Brava, São Salvador and Peixe Angical. The study was carried out at 20 sampling points in different seasonal periods. We performed a beta diversity analysis between the tributaries and the central body of the reservoirs, between the points located only on the central body of the three reservoirs and between the tributaries, to verify the similarity in the structure of the communities between the different regions. The highest beta diversity, in other words, the lowest similarity in the structure of zooplanktonic communities, was obtained between the sampling points located in the tributaries and in the central body of each of the studied reservoirs, mainly the rainy season, demonstrating the influence of seasonality. The abiotic factors were also different when comparing the dry and rainy periods, especially in the tributaries. The lowest values of beta diversity were measured comparing the central body of the reservoirs, mainly for rotifers and microcrustaceans. This result demonstrates the importance of the longitudinal dispersion of these groups among the reservoirs. Besides, considering the low richness of exclusive taxa inside the reservoirs (in the central body), we can infer that the dispersion of taxa from the tributaries to the central body is important, and the population size of some species will be favored under the lentic conditions of the reservoirs, changing the structure of communities. This study contributes to a better understanding of the factors responsible for the diversity of zooplanktonic community in reservoirs, considering the abiotic component, the importance of longitudinal and lateral (tributary) dispersion of the different zooplanktonic groups and the seasonal component.
Evolução do tamanho corporal de Amazona (Aves: Psittacidae) em ilhas
(Universidade Federal de Goiás, 2022-03-25) Porto Netto, José Queiroz; Diniz Filho, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351; Diniz Filho, José Alexandre Felizola; Soares, Thannya Nascimento; Jardim, Lucas Lacerda Caldas Zanini
The changes in insular species in which large-bodied species reduce its size (dwarfing) and small-bodied species increase their size (gigantism) is called the Island Rule. Available models to explain this differentiation seek to assess how species with different body sizes respond evolutionary to biotic and abiotic ecological factors on the islands. In this study, six characters were evaluated to verify the tendency of differentiation in body size and other morphological characteristics in insular species of parrots of the genus Amazona. The presence of this trend was evaluated comparatively by the Si ratio between the body size between the insular species and the presumed continental ancestor, defined from a phylogeny of the genus and accessed by a Phylogenetic Generalized Least-Squares (PGLS). We also evaluated the evolutionary processes involved in this change through evolutionary quantitative genetic models for the differentiation of Amazona guildingii, contrasting effects of genetic drift and natural selection. We found differences in body size in the continent/island transition, but not following the pattern expected by the island rule; the body size of Amazona species does not show a clear relationship between Si values and ancestral body size. For A. guildingii, we found that the character differentiation is explained by natural selection and not by genetic drift, especially for wing size and body mass. We conclude that the island rule pattern cannot be generalized to the genus Amazona, although there is evidence of natural selection acting on differentiating the body size generating insular gigantism.
Definição de áreas prioritárias e representação da biodiversidade aquática da região hidrográfica do Paraná em unidades de conservação e terras indígenas
(Universidade Federal de Goiás, 2022-07-26) Costa, Álvaro Marin; Loyola, Rafael Dias; http://lattes.cnpq.br/7649189080736923; Loyola, Rafael Dias; Brum, Fernanda Thiesen; Diniz Filho, José Alexandre Felizola
Aquatic ecosystems are among the richest in biodiversity on the planet but also the most threatened. For this, most of them are protected. However, in Brazil, the creation and expansion of conservation units are biased towards terrestrial ecosystems and focused on the Amazon. Planning for the conservation of aquatic environments is a gap in scientific and applied practice, although it is an important trend in the scientific literature. Therefore, in this dissertation, we evaluated the representativeness of the biodiversity of freshwater fish and aquatic flora of the Paraná Hydrographic Region in its current network of conservation units and indigenous lands, as well as proposed priority areas for the conservation of these species. We find that 6.3% of the region is protected. However, on average, less than 10% of the distribution of the species is covered. Furthermore, our spatial prioritization analyses show that the increase in 30% of protection in the region would cover an average of 48% of the species distribution. Results like these can be used to support the planning and implementation of conservation actions aimed at protecting and managing the aquatic biodiversity of this hydrographic region.
Uma abordagem quantitativa para a seleção de espécies para a restauração ecológica baseada em diversidade funcional
(Universidade Federal de Goiás, 2018-03-16) Tsujii, Paula Kiyomi; Carlucci, Marcos Bergmann; http://lattes.cnpq.br/1141743724585455; Carlucci, Marcos Bergamann; Loyola, Rafael Dias; Vieira, Daniel Luís Mascia
O autor não apresentou resumo em outra língua.
A influência do tamanho de área protegida na composição e conservação de aves no Cerrado
(Universidade Federal de Goiás, 2011-07-27) Pereira, Caio Stuart Amorim; Bastos, Rogério Pereira; http://lattes.cnpq.br/6015137404238990; Bastos, Rogério Pereira; Ferreira, Anamaria Achtschin; Bispo, Arthur Ângelo
The Cerrado has a huge variety of ecosystems are able to offer resources and conditions for more than half of the birds found in Brazil. Its great extent and location on the continent favors contact with birds of different biomes. All this diversity of birds is threatened by processes that reduce natural cover your area. The selection of protected areas is aimed to represent the largest number of local species and their populations remain viable over time. This strategy is used from the predictions of the theory of island biogeography implies a positive relationship between the size of the area and its species richness. Other important elements of biodiversity may be absent only selected areas of the potential size of the area. In a protected area of the Cerrado conducted a field study in which we ascertain the status of endemism and threat to local bird community analyzed the influence of seasonality on the composition of its avifauna. In the second part of our work grouped the 12 species in protected areas in the Cerrado by their similarities in the use of resources in the environment. We tested the relationship between area size and species richness considering the variations in the composition of functional groups and number of endemic species and / or threatened. We discussed how big an area can influence the priorities for bird conservation in the biome. We found that the area has a strong influence on the number of species from one location. However, we point out some aspects that highlight a set of small areas in the conservation of bird diversity in Cerrado.
Seleção de recursos por duas espécies de besouros bruquíneos do gênero Gibbobruchus na planta hospedeira Bauhinia Curvula Benth
(Universidade Federal de Goiás, 2013-04-09) Bergamini, Leonardo Lima; Almeida-Neto, Mário; http://lattes.cnpq.br/1000297113793647; Almeida-Neto, Mário
The process of host-plant selection is the main interface in the herbivore-plant interactions, with deep consequences for the ecology and evolution of those groups. In this work, we investigate some steps of the host-plant selection in two congeneric species of seed beetles. In the first chapter, we assess the oviposition pattern and larval survival in the seed-beetle G. cavillator to evaluate whether oviposition site choices maximize offspring survival, accounting for the spatially hierarchic structure of the system. In the second chapter, we analyze the fine-scale positioning of G. speculifer eggs, and explore the role of geometric constraints in the egg distribution patterns. Altogether our results exemplify how small differences in key traits of the host-plant selection can lead to significant differences in the interaction between herbivore insects and their host plants.
Padrões de distribuição de mamíferos de médio e grande porte em paisagens fragmentadas
(Universidade Federal de Goiás, 2012-01-03) Bernardo, Paulo Vitor dos Santos; Oliveira, Arthur Ângelo Bispo de; http://lattes.cnpq.br/1100433822757573; Melo, Fabiano Rodrigues de; http://lattes.cnpq.br/6863533704023271; Pedro, Wagner André; Marco Júnior, Paulo De; Melo, Fabiano Rodrigues de
Habitat fragmentation is defined as the breaking of a continuous habitat in “patches” or fragments. This process leads to environmental changes capable of affecting communities in different ways, causing species composition changes. Beta diversity measures can show the variation between the composition of different communities, where two ecological patterns can be found: turnover and nestedness. In turnover the variation in community structure is a consequence of species replacement, while in the nestedness poor communities are nested in richer communities. Here I tested: (I) how habitat fragmentation affects the presence of large e medium sized mammals in different functional groups; (II) if the variation in beta diversity in fragmented landscapes is caused by turnover or nestedness, and (III) if the variation observed was due to habitat fragmentation. I used 19 Semidecidous Forest patches in the Brazilian Cerrado, from the State of Goiás. Landscape metrics from 2.5 km around the patches were obtained from classifications and measurements. For the analyses, I made four sets based in diet, size, diet amplitude and all previous three together. I calculated the beta diversity with Sorensen indices, turnover with Simpson indices and nestedness with Nestedness indices. The natural area size influenced the group B3- felines and the core area percentage, the groups A1-carnivores, larges and B3-felines. The core area percentages were the most important character in fragmented landscapes for mammal communities. The felines were the most sensible group. This group was affected by natural area availability and by the core area percentage. The beta diversity pattern in the fragmented landscapes was turnover, but it was not related to environmental variation or spatial distances between the landscapes. Both nestedness and beta diversity were affected by spatial distance, but beta diversity was also affected by environmental variation linked to landscape connectivity. The changes in different landscapes cause different responses in species and allow the creation of a fragmentation gradient, driving the turnover phenomenon. The carnivores were the species most sensible to habitat fragmentation, mainly because they need large home ranges. Thus, an understanding of how diversity reacts to habitat fragmentation may provide support to the implementation of conservation areas and research upgrading which focus specific species groups. Managed areas with large core areas and good connectivity should bring desirable results for large and medium sized mammals conservation status. This affirmative is true, especially for larger mammals and carnivores.
Riqueza e composição de mariposas Arctiinae (Lepidoptera, Noctuidae) em diferentes formações vegetais em uma área de cerrado
(Universidade Federal de Goiás, 2012-05-17) Santos, Carolina Moreno dos; Ferro, Viviane Gianluppi; http://lattes.cnpq.br/4073294502295550; Ferro, Viviane Gianluppi; Vasconcelos, Heraldo Luiz de; Almeida Neto, Mário
The Cerrado Biome presents a mosaic of vegetation ranging from open areas with no shrub component (grassland) to areas with a high density of tall trees (forests formations). This mosaic of vegetation that occurs in the Cerrado harbors a high biodiversity of different groups of animals and enables to this biome presents high beta diversity in the region. However, data of species occurrence are lacking for most groups of animals, especially for the invertebrates. In this work, Arctiinae moths were sampled in different vegetation formations of the Cerrado. Arctiinae are one of the richest subfamilies of Lepidoptera. About 11.000 species were described in worldwide, 6.000 in the Neotropics, 1.400 in Brazil and 720 in the Cerrado. Most larvae of Arctiinae are polyphagous. In addition to eating the green angiosperm and gymnosperm tissues, their ranks include species that consume algae, lichens, liverworts and mosses. Despite being polyphagous, the most species of Arctiinae feed mainly on the plant species that provide secondary metabolities (mainly pyrrolizidine alkaloids) that offer to them chemical protection against natural enemies. Thus, variations in the host plant species composition reflect at least partially in the variations in the moths species composition. In the first chapter of this dissertation, the Arctiinae moth fauna was characterized in four vegetation formations (dirty grassland, closed grassland, cerrado sensu stricto and semideciduous forest). Moths species richness was significantly higher in vegetation formations more structurally complex. The moth species composition in semideciduous forest was significantly dissimilar from the others vegetation formations. There was a positive correlation between the moths similarity patterns and the plants similarity patterns. In the first chapter was also tested the premise that structurally simple habitats presents a higher intensity of predation because they available less quantity of refuges for prey. This premise was corroborated because the predation intensity on artificial caterpillars was twice higher in the dirty grassland than in the structurally complex vegetation. In the second chapter of this dissertation was tested which environmental variable best determines the variation in Arctiinae species richness and composition between the vegetation formations of the cerrado sensu lato (dirty grassland, closed grassland and cerrado sensu stricto). The trees richness was the most determinant of moths species richness. The moth species composition was influenced by the trees richness, followed by herbs density, predation intensity and by the variation coefficient 3 of tree height. The results that the vegetation characteristics are the best predictors of the variations in the moths species richness and composition indicate that it is necessary to invest in conservation measures of all vegetation formations that occurs in the Cerrado.
Padrões de evolução do nicho climático e de diversificação em anuros neotropicais
(Universidade Federal de Goiás, 2014-05-26) Braga, Pedro Henrique Pereira; Marco Júnior, Paulo De; http://lattes.cnpq.br/2767494720646648; Maciel, Natan Medeiros; http://lattes.cnpq.br/2116561844584292; Camacho, Crisóforo Fabricio Villalobos; Nabout, João Carlos; Maciel, Natan Medeiros
Understanding how important species traits are distributed across evolution is a major task for evolutionary ecologists and comparative biologists. Here, we addressed evolutionary questions about the niche evolution and diversification among anuran species. We performed analyses of the climatic niche evolution and diversification rates of direct and indirect development Neotropical anurans with the use of multivariate description of the species’ climatic niche and modern phylogenetic comparative methods. We tested the predictions that due to high physiological dependence to water, (i) frogs with biphasic life cycles (indirect development; free-larval form present) tend to retain their ecological niche characteristics across evolution (i.e., phylogenetic niche conservatism) and (ii) the climatic niche of direct development anurans evolved faster than the climatic niche of anurans with indirect development. We also hypothesized that, because of the role of niche conservatism in promoting allopatric speciation, indirect development anurans would also have higher diversification rates than direct development anurans. By including a high number of sampled species, we showed that there are no differences in their actual macroecological climatic niche. However, although niche position is similar between groups, indirect development anurans showed phylogenetic conservatism in their climatic niche, whilst direct development anurans evolved their niche according to the null expectation. Our assessments of diversification rates indicate that there is a correlation between terrestrial development and decreased diversification in anurans in a more general way and that faster speciation and reduced extinction in the Neotropics contribute to higher diversification in indirect development anurans. We consider that the insertion of larval characteristics can, therefore, imply in obstruction in the evolution of the environmental niche of a clade. We also believe that the evolution to different niches set by the different environmental requirements (here, one terrestrial and other fully or semi aquatic) resulted in divergent adaptive peaks (fitness valleys and trade-offs between adaptation to different environments), to which both direct and indirect development anurans evolved to match.
Algas perifíticas: uma abordagem taxonômica e funcional em riachos inseridos em paisagens modificadas de cerrado
(Universidade Federal de Goiás, 2021-08-31) Oliveira, Pedro Henrique Francisco de; Nabout, João Carlos; Nabout, João Carlos; Bortolini, Jascieli Carla; Ferragut, Carla
Considering the hierarchical conformation and connectivity present in dendritic drainages, the hydrological structuring of these systems may favor approaches to studies associated with patterns in aquatic metacommunities. Thus, investigating patterns in metacommunities using aquatic microorganisms as a study tool may favor approaches to studies associated with patterns of dispersion or species limitation, such as mass effects and species sorting. In addition, it is understandable to think that different functional traits present in species that make up these metacommunities may be modulated by environmental components (fundamental niche/realized niche) or spatial factors within an environmental gradient. In the present study, the first chapter “Effect of local, regional (land use) and spatial (organism dispersion) environmental variables on the structure of the periphytic algal community in Cerrado streams”, we seek to assess the relative importance of local environmental components (limnological), regional (land use) and spatial (dispersion capacity) variables for the periphytic community in Cerrado streams along the Piracanjuba River sub-basin. For the second chapter “Functional composition of periphytic algae in Cerrado streams inserted in modified landscapes”, we investigated how the functional traits present in species that make up the periphytic community respond to the variation of the regional (landscape) and local environmental component limnological variables) in streams inserted in modified Cerrado landscapes. We found 127 species, with a predominance of the Bacillariophyceae class in all streams and the average of remaining vegetation for the extension of the Piracanjuba River sub-basin was 40%. The periphytic community showed greater species replacement along the hydrographic network and relative importance only of the spatial component, since the functional attributes observed for this community were different along two gradients, nutrient availability, and percentage of natural remaining vegetation, respectively.
Padrões de distribuição e riqueza de espécies troglóbias no Brasil
(Universidade Federal de Goiás, 2020-08-31) Dias, Priscila de Araújo; Rangel, Thiago Fernando Lopes Valle de Britto; http://lattes.cnpq.br/1613666671361533; Rangel, Thiago Fernando Lopes Valle de Britto; Domingos, André Menegotto; Diniz Filho, José Alexandre Felizola
Caves have environmental conditions different from the surface, subjecting the subterranean fauna to different selective pressures. Species highly adapted to the subterranean environment are called troglobias, and share an evolutionary history of adaptation in aphotic environments with few nutrients. One of the explanations for the emergence of these species is provided by the hypothesis of Climate Change, in which cave populations maintained a gene flow with the surface, but glacial events and ecological factors ended up isolating them geographically and genetically. An alternative explation is provided by the Adaptive Deviation hypothesis, in which the populations that invaded the caves in search of resources suffered new selective pressures, and when the colonization was successful the population expanded in the underground habitat, reducing the gene flow with the epigeal populations. The goal of this study is to analyze which process determines the distribution and richness patterns of troglobic species in Brazil, to identify the influence of paleoclimatic events in the region and to analyze whether the distance between caves affects the structuring of the community. In addition to estimates of tetrapod richness we also used paleoclimatic data from the last five million years, including temperature, precipitation and primary productivity. The results showed that the regions with the greatest wealth are highly correlated with the greatest variation in temperature, and the least variation in precipitation. Data on primary productivity and tetrapod richness did not show significant correlation.
Aninhamento de assembleias de aves em arquipélagos oceânicos
(Universidade Federal de Goiás, 2021-08-26) Caetano, Vinne Magalhães; Melo, Adriano Sanches; http://lattes.cnpq.br/4602365265261727; Melo, Adriano Sanches; Maestri, Renan; Almeida Neto, Mário
The species richness of an island can be driven by the quality, complexity and heterogeneity of the habitat, as well as the dispersal ability of the species. Island size and altitude can be used as surrogate variables for habitat attributes, and island isolation can be used to represent the dispersal ability of species. Communities on a gradient of isolation or environmental complexity can form a taxonomically and/or morphologically nested distribution pattern. I tested the morphological nesting of bird assemblages from islands of eight oceanic archipelagos for size, altitude, and isolation of their islands. I performed this test by weighting the nesting by the magnitude of the difference between the tested variable and without this weighting. I found that morphological nesting was predominantly relevant to size and altitude, while isolation was not able to explain nesting in any archipelago. Unweighted analyzes had more positive results for nesting than those weighted by difference in altitude, size or isolation. The nesting observed was more due to richness shared between communities than due to the tree topology of morphological similarity between species. This means that if a community shares similarity in attributes with other communities, this similarity in attributes comes from the species shared between these communities and not from different species with similar attributes. Isolation was not able to explain the nesting, however, it is possible that there are isolation measures with greater biological relevance.
Overkill, sítios de matança e as evidências de interação homem megafauna na América do Sul
(Universidade Federal de Goiás, 2021-12-30) Bampi, Hugo; Ribeiro, Matheus de Souza Lima; http://lattes.cnpq.br/9592727826334407; Ribeiro, Matheus de Souza Lima; Faleiro, Frederico Augusto Martins Valtuille; Terribile, Levi Carina
During the end of the Quaternary, humans exploited (hunting/scavenging) megafauna across the Americas. However, South American (SA) megafauna kill/scavenge sites (MKSSs) have been persistently underestimated or even neglected by researchers, biasing further analyses such as the human impact on megafauna extinctions. Here, we systematically review the evidence of exploitation in the South America, test overkill hypothesis in SA, compare its quantity and quality against exploitation data from North America, and suggest the cause of South American data bias. A total of 18 and 17 SMDMs were found in AS and North America (NA), with 15 and 5 genera explored by humans. South American overkill was not supported by these empirical data. AS is neglected by researchers from the Northern Hemisphere (with an emphasis on North Americans). SA does have quantitative and qualitative data similar to or better than NA on the exploitation of megafauna. We suggest that the reason for this pattern is a linguistic bias (shortage of reading works written in Latin languages by researchers from the northern hemisphere). This dissertation contributed to a greater understanding of humanmegafauna interactions and overkill in the Americas. We emphasize the importance of reducing the linguistic bias to further advance the discussion on the extinction of megafauna in the Quaternary
Florística e ecologia de musgos (Bryophyta) na Floresta Nacional de Silvânia, Goiás
(Universidade Federal de Goiás, 2010-09-30) Porfirio Junior, Eder Dasdoriano; Klein, Vera Lúcia Gomes; http://lattes.cnpq.br/6477452328378345; Klein, Vera Lúcia Gomes; Felisberto, Sirlene Aparecida; Guimarães, Frederico Augusto
Facilitation is an important ecological process, however, still little studied for biological communities. Recently ecology re-examined the positive effects between species and such area has being the focus of ongoing studies and research worldwide. Mosses (Bryophyta) have ecological particularities that make the group a good indicator of micro-and microclimatic changes. However there are few studies aimed to identify patterns of ecological groups in Brazil are still limited and more studies addressing the ecology of bryophytes in the Brazilian Cerrado. It is known that the cerrado has a mosaic of vegetation types ranging from savanna and forest. And that this gradient presents great variability of factors such as occurring species, temperature, humidity and light incidence. Faced with this panorama, this study sought to relate how communities of mosses in areas of cerrado sensu stricto respond to the occurrence of Syagrus flexuosa. The study took place in the Floresta Nacional de Silvania initially the mosses were collected from all the faces in this Conservation Area. Were subsequently selected 50 plots measuring 25 square meters (5x5m) randomly distributed in the cerrado sensu stricto. Data were collected from plots of temperature, coverage of Syagrus flexuosa, humidity, distance from plot to nearest forest formation, diversity, richness and moss substrates occurring in the plots. Cover classes were created in S. flexuosa, Class I shares with coverage less than or equal to 33% of the share by S. flexuosa Class II shares with coverage exceeding 33% and less than 66% and Class III shares with coverage greater than or equal to 66% by Syagrus flexuosa. We found through an analysis of variance (ANOVA) decrease in temperature in the plots with higher cover of S. flexuosa (F2, 47 = 42.73, p <0.001). The relative decrease in measured temperature between the classes was 3 ° C between classes I and III, indicating that the coverage of S. flexuosa acted effectively in temperature. Analysis of variance (ANOVA) to relate the classes of coverage and richness of mosses found in the plots indicated that portions of Class I and II had similar richness and portions of Class III have a wealth on average, four times greater (F2, 47 = 38.87, p <0.001). The ANOVA performed between the classes of coverage and the abundance of mosses showed a similar pattern to the richness and abundance of mosses found a much larger plots of Class III (F2, 47 = 43.57, p <0.0001). The linear regressions performed using the distance between the plots and the forest was negatively related to wealth and diversity of species. The occurrence of mosses Fabronia ciliaris var. polycarpa, Pilotrichella flexilis and Syrrhopodon ligulatus occurred only in plots with high coverage of Syagrus flexuosa and generally about the area of interference of the palm. Species of shade Pilotrichella flexilis and Syrrhopodon ligulatus were found mainly in the installments of Classes II and III. The forms of life found in the plots were also mostly those considered resistant to desiccation (cushion and tuff) 65%, however 89% of the occurrences of life forms less resistant to desiccation (frame and mat) occurred in plots with greater coverage S. flexuosa. Studies comparing more restricted areas of savanna are required so that data can be compared and define the absence or presence of patterns.
Diversidade beta temporal como ferramenta para análise de impactos ambientais
(Universidade Federal de Goiás, 2021-07-29) Tedesco, Aline de Oliveira; Carvalho, Priscilla de; http://lattes.cnpq.br/4723821511788681; Carvalho, Priscilla de; Bortolini, Jascieli Carla; Vieira, Ludgero Cardoso Galli
One of the goals of ecology is to analyze the influence of anthropogenic impacts on biological diversity. Beta diversity analysis can be considered an important tool to measure how environmental impacts can modify species composition, both in spatial and temporal scales. This measure is useful because it allows comparing the periods before and after the impact. Considering the large number of studies using beta diversity to measure some type of environmental impact, the first chapter of this work had the main objective of conducting a systematic review of the existing literature on the subject. This work showed that Brazil is the third country that has published the most on the subject. Besides, plants, followed by fish, are the most studied organisms. This review also demonstrated that, in most studies, the measure of beta diversity decreased after impact. In other words, biotic homogenization occurred after impact. The work also suggests some gaps that need to be filled. In the second chapter, a case study was carried out on the temporal variation of the zooplankton community in a stretch of the Tocantins River, after the construction of a hydroelectric plant, covering a period of 12 years. In this study, beta diversity was calculated using the method proposed by Legendre (2019), which allows identifying the gain and loss of species in the study area. When comparing the periods before and after the formation of the reservoir, the gain of species was greater than the loss. Probably the main factor responsible for the high values of beta diversity was the transformation of lotic to lentic environment. Therefore, the two chapters of this dissertation demonstrated the wide use of beta diversity indices and the importance of this tool in the analysis of environmental impacts.

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