Doutorado em Ecologia e Evolução (ICB)
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Navegando Doutorado em Ecologia e Evolução (ICB) por Por Orientador "De Marco Júnior, Paulo"
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Item Invasões biológicas: indo além dos modelos de distribuição na busca de predições realistas sob restrições energéticas(Universidade Federal de Goiás, 2020-03-25) Andrade, André Felipe Alves de; De Marco Júnior, Paulo; http://lattes.cnpq.br/2767494720646648; De Marco Júnior, Paulo; Diniz Filho, José Alexandre Felizola; Silva, Alessandra Bertassoni da; Vieira, Marcus Vinícius; Paglia, Adriano PereiraBiological invasions are one of the mains threats to biodiversity in the Anthropocene. The introduction of new exotic species might have serious consequences to native communities, being responsible for modifications to the established biotic relations up to the extinction of native species. Apart from serious ecological consequences, invasive species are also relevant form the economic point of view, as many species reach high populational levels which can lead to losses for several economic activities, such as agriculture and hydroelectric energy generation. Given the relevance of invasive species, an essential aspect to reduce the losses caused by biological invasions is to get ahead of the invasion process and prevent a potential invasive species from ever reaching a new region. In order to reach this goal, the different methods should be effective in anticipating possible invasions, by accurately defining target regions and also how the invasive species will interact with the native community. In this thesis we built and tested several models that seek to improve our capability to anticipate the results of an invasion process in its several stages. In the first chapter we explored the capability of ecological niche models (ENMs) in identifying suitable areas for the occurrence of a potential invasive species. ENMs are commonly used for establishing areas of interest, based on species’ suitability. However, as we demonstrate in this first chapter, mismatches between the realized and the fundamental niche may lead to patterns of consistent under-or overprediction of the areas considered as harbouring suitable climatic conditions for an invasive species. At the second chapter we explored how the interaction between the different life-history strategies of invasive species and the native community determine invasion success. We’ve built a realistic system in which individuals compete for energy and have priorities for allocating the obtained energy. The whole system is regulated by allometric relations and energetic budgets. We found that invaders that share a common life-history strategy with the native species were more successful in establishing in the system, being that the strategy with the higher gains was of living longer, accumulating reserves while reducing the reproductive output (less offspring with longer gestation periods). At the third chapter we explored how those life-history strategies behave under a realistic landscape, with a real land-use and fluctuations in the energy within the system. In this chapter we’ve improved the chapter developed at the chapter 2 and focused on answering questions related to the landscape configuration and invasive-native co-occurrence under different levels of landscape heterogeneity. We also evaluated our model under classical hypothesis related to the invasion process. We’ve evaluated invasion success over 18 years in a landscape undergoing a rapid agriculture expansion and found that invasion success was highest at the end of this period, when the landscape is with its highest agriculture coverage. Agriculture expansion, by itself, was responsible for the extinction of native species, besides increasing invasion success and the co-occurrence between invasive and native species. There was also a difference in successful life-history strategies, in a way that the spatial configuration plays a big role in determining invasion success.Item Características de história de vida de árvores do Cerrado direcionando o futuro e a adaptação aos impactos das mudanças climáticas(Universidade Federal de Goiás, 2013-06-28) Côrtes, Lara Gomes; Cianciaruso, Marcus Vinicius; De Marco Júnior, Paulo; http://lattes.cnpq.br/2767494720646648The speed of climate change nowadays brings unprecedented challenges to biodiversity conservation. As environmental conditions are important factors in determining the geographical distribution of species, the latter should change their distribution with changes in climate, rearranging communities with gains and losses of species. Aiming to identify vulnerabilities and propose proactive conservation to increase the adaptation of species to climate change we did an approach with species distribution models, an essential tool to predict the species potential distribution in different climatic scenarios. An important understanding in this changing scenario is the knowledge of what life history traits may make species more susceptible to changes in climate and then, may be possible, if such characteristics are related to specific environmental conditions, defining the ecological niche breadth of species as well as their geographic distribution. We sought to identify whether simple life history traits of trees occurring in the Cerrado could be related to the size of the niche and distribution area, and if the species with characteristics associated with a small area distribution and restrict niche breadth would be more predisposed to extinction due to climate change. It was found that the evergreen generalist species have lower potential distributions, evergreen species from broad sense cerrado have smaller latitudinal ranges and height proved to be related to the geographic distribution of broad sense cerrado species. Still trying to identify potential impacts on biodiversity and ecosystem function, assuming the environmental conditions as selective filter of species with life history traits that guarantee a higher performance in a new climate, it was tested if climate change reduces the functional diversity of communities in sub-basins of the Cerrado. There was a large reduction in richness, but an increase in functional diversity, since most communities lost species functionally redundant, but which can act as an insurance against loss of ecosystem functions. Thus, the future communities will be more vulnerable to other disturbances, such as habitat loss and fragmentation. In this context, proactive a that can increase the connectivity of ecosystems will be essential for the biodiversity conservation to climate change. Thus, we propose a systematic planning of restoration to complement the establishment of protected areas and, simultaneously, selected areas of lower socioeconomic conflict and climate stability. The restoration should be understood as an important proactive conservation action in a changing world that is full of increasingly fragmented ecosystems as the Brazilian Cerrado.Item Padrões metacomunitários de insetos aquáticos de riachos florestados da Amazônia(Universidade Federal de Goiás, 2015-03-20) Nogueira, Denis Silva; De Marco Júnior, Paulo; http://lattes.cnpq.br/2767494720646648Lotic ecosystems are highly complex interacting with acting factors in different spatial and temporal scales. Small forested streams receive direct influence of the surrounding vegetation through the input of organic matter which is the base of the food chain in these ecosystems. I studied the effect of the reduced-impact selective logging on communities of aquatic insects streams to test the hypothesis that communities are affected by their impacts. Despite the metrics used appropriately capture the impact, there were no negative effects on insect communities. However, the results of this study may not be generalizable to other systems because we studied only a fraction of the diversity of Amazonian streams, specifically the insect orders Trichoptera, Plecoptera and Coleoptera. In addition, the absence of the low impact management effects is dependent on the operating system adopted in each enterprise. Another predominant feature in any lotic ecosystem is its directional flow, which consequently affects the distribution of substrates, habitats, and food resources within the streams. I studied the effects of water flow taking it as the main predictor of the selective effect of habitat on the attributes of insect taxa. My hypothesis was confirmed by showing that most rapid flowing streams in Amazon has faunas with morphological and ecological attributes of greater resistance to flow. Environmental factors such as the preference for habitats, dispersive limitation and biotic interactions are among the main mechanisms responsible for structuring communities, and has been widely emphasized in the context of metacommunity theory. A metacommunity is defined as the set of communities in a region which are interconnected by the flow of individuals, which emphasizes the spatial dynamics in structuring the diversity and composition of species in each local community. I tested the effects of environmental factors, spatial filters and biotic interactions in aquatic insects of forested streams of the Amazon, specifically the intraguild segregation and interguild predation effect. My results support the existence of predation effects on the organization of the metacommunity, as evidenced by the exclusive fraction of the predators matrix on prey assemblages of different guilds, and still withstand environmental effects and dispersive limitation in different trophic guilds. The study developed in this thesis help us understand more clearly the effects of the selective logging impacts on aquatic insect communities, assist in understanding about what are the characteristics of the stream habitats filter ecological and morphological attributes of aquatic insects in the Amazon, and advance our understanding of the effects that biotic interactions may have on the structuring streams metacommunities.Item Considerações sobre a biodiversidade de abelhas brasileiras: vícios de coleta, distribuições potenciais e fragmentação(Universidade Federal de Goiás, 2014-02-28) Silva, Daniel de Paiva; De Marco Júnior, Paulo; http://lattes.cnpq.br/2767494720646648; Marco Júnior, Paulo De; http://lattes.cnpq.br/2767494720646648; Bini, Luis Maurício; Nabout, João Carlos; Noll, Fernando Barbosa; Vital, Marcos Vinícius CarneiroThe world we live in faces fast and intense environmental changes, deeply related to human activities, which directly or indirectly are related to the current biodiversity crisis. Thus, the existence of quality biological, ecological, and distributional data is of utmost importance for the support of active conservation practices. Nonetheless, both Linnean (lack of taxonomical data) and Wallacean (lack of distributional data) shortfalls are important setbacks hindering the effectiveness of conservationist decisions. The data harbored in museums and overall collections is excellent to support conservational measures. Nonetheless, usually this data is biased and needs to be adequately filtered before being used. Insect and arthropod species are under sampled, what impedes them to be properly considered under Conservation Biogeography frameworks. In such scenario, even insect groups with relatively known biology and ecology are neglected in practical conservation actions. Despite that, with the advent of new computational tools allied with good theories and good distributional data of insect species, it is possible to contemplate those biological groups in concrete and efficient conservation actions. Therefore, in the first part of this thesis, considering bees from the Megachile genus (Chapter 1) and from the Meliponini tribe (Chapter 2), we evaluated potential biases affecting those data, but also evaluate potential areas for new field surveys. The Wallacean shortfalls are commonly used to justify the implementation of new field surveys. Therefore, in the second part of this thesis, we used the new occurrences of the bee species [Aglae caerulea (Apidae: Eulgossini) – Chapter 3; and the exotic species, Lithurgus huberi (Apidae: Lithurgini) – Chapter 4] allied with distribution modelling to predict these species potential distributions and indicate areas for future new samplings. On the third and last part of the thesis, we considered a regional spatial scale and habitat loss and fragmentation questions to address their effects on the bee biodiversity from the Cerrado biome found within the Goiás state. In Chapter 5, we evaluated the effects of anthropic areas amount and their isolation on two orchid-bee species from the Cerrado (Eulaema nigrita and Eufriesea auriceps), which apparently are not affected by the increase of anthropic areas in this biome. Later, in the last chapter (Chapter 6), we evaluated the response of all bee community we sampled in Cerrado areas within state of Goiás, as well as the sub groups of eusocial and solitary species, to the landscape structure of our sampling areas, considering different local spatial scales.