Doutorado em Ecologia e Evolução (ICB)

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http://200.137.215.59/tede/handle/tde/203

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Avifauna em áreas de mineração: diversidade e conservação em Niquelândia e Barro Alto GO
(Universidade Federal de Goiás, 2011-03-25) CURCINO, Alexandre; KLEIN, Vera Lúcia Gomes; http://lattes.cnpq.br/6477452328378345
In the fixed point methodology, the observer remains for a predetermined time, recording all birds registered by observation or hearing. Widely used in temperate regions, the methodology has been used in Brazil, where it has suffered adaptations through the years. Whereas the current studies show different sampling times of methodology (10, 15 and 20 min), the aim of this survey was to compare the birds richness estimated for the sampling times of 10 and 20 minutes, in cerrado, gallery forest and vereda, in the regions of Niquelândia and Barro Alto - Goias and verify the effectiveness of bird detections per hour of study for different sampling situations and travel times between fixed points. The survey in Niquelândia occurred in 2007 and 2008. Barro Alto, in the years 2008 and 2009. At each location were established 20 point counts, and sampled five points between 6h00min and 8h40min. The points were drawn for 10 min and 20 min sampling . The results suggest that the researcher who remains 10 min at each point obtain the same statistical results that the researcher who remains 20 min at each point. The species detection efficiency is related to the balance in the choice of sampling time and displacement in order to increase the chances of finding rare species, and at the same time, maximize the number of detections.
Biogeografia da conservação frente à expansão agrícola: conflitos e prioridades
(Universidade Federal de Goiás, 2012-04-10) DOBROVOLSKI, Ricardo; LOYOLA, Rafael Dias; http://lattes.cnpq.br/7649189080736923; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351
Agriculture is the human activity with the greatest impact on the environment. Specifically, it represents the greatest threat to biodiversity. In the future, this activity should expand due to population growth, increased consumption and production of biofuels from food. To understand the possible impacts of this expansion on biodiversity, we used scenarios of land use change between 1970 and 2100 from IMAGE (Integrated Model to Access Global Environment) to test the following hypotheses: (i) areas considered as global priorities for conservation by international NGOs will be preferentially impacted by agricultural expansion in the XXI century, (ii) there is a conflict between the priority areas for carnivores conservation and agricultural expansion, and this conflict can be reduced by incorporating information on agricultural expansion in the prioritization process, (iii) the integration among countries for conservation planning may benefit both biodiversity and agricultural productivity, (iv) Brazilian protected areas will be impacted by agricultural expansion in the future and this impact will differ between protected areas of integral protection and those of sustainable use. We found that: (i) the impact on priority areas for conservation depends on the criteria by which they were set, so that areas defined by its high vulnerability are currently most affected than those of low vulnerability. Throughout the XXI century this impact is expected to increase, although the difference between the two types of priorities remains, except for High Biodiversity Wilderness Areas, defined by their low vulnerability in current time, but for which most pessimistic scenarios forecast an impact similar to priority areas of high vulnerability, (ii) there is a high spatial congruence between areas with high agricultural use in the future and priority areas for conservation of carnivores. This conflict can be reduced if the prioritization process include information on agricultural expansion; this incorporation, however, causes a profound change in the distribution of priority areas and reduces the number of protected carnivore populations, (iii) the integration of countries to create a set of priority areas for conservation that represents 17% of the land surface can protect 19% more mammal populations without reducing food production, compared to a strategy in which each country seeks to protect its territory independently, and (iv) the impact of agriculture in Brazil is expected to increase until the end of the century, threatening even the protected areas and their surroundings. This impact, however, should not be different between areas of sustainable use and those of integral protection. We conclude that agricultural expansion should remain a major threat to biodiversity in the future, even in areas of special interest for conservation. Conservation actions should be planned taking into account this threat in order to reduce their potential impacts. For this, countries like Brazil should strengthen its surveillance on agricultural expansion and on how this activity is developed. Furthermore, the integration of international conservation efforts should be pursued, given its benefits for biodiversity and food production. Finally, humanity must choose methods of agricultural production that reduce its impacts, including avoiding its future expansion, so as to meet the increasing needs of a human population globally.
Bionomia de Odonata: implicações ecológicas na distribuição de riqueza, na diversidade Beta e no uso como indicadores ambientais
(Universidade Federal de Goiás, 2011-04-28) DUTRA, Silvia Leitão; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648
Ecologia de insetos aquáticos em córregos do Cerrado: do nicho hutchinsoniano ao distúrbio intermediário
(Universidade Federal de Goiás, 2010-06-18) GODOY, Bruno Spacek; COELHO, Alexandre Siqueira Guedes; http://lattes.cnpq.br/0840926305216925; OLIVEIRA, Leandro Gonçalves; http://lattes.cnpq.br/8837912214958454
The Cerrado region is the second largest biome in Brazil, covering nearly 22% of the national territory. Due to a facility provided this biome for handling and cultivating the soil, the Cerrado has been suffering an intense change in its landscape, increasing the impact in all it s natural systems. Thru a systemized sampling of 101 streams in the Rio das Almas River Basin region, center of Goias, it was observed how such change in landscape changes the community of benthonic water insects. Initially it was not observed changes in the number of genres for different river sizes. Impact raise, especially in the riparian zone leads to a reduction in the number of genres of Ephemeroptera, Plecoptera and Trichoptera. The communities in impacted streams are subsets of communities in pristine localities, showed a nestedness pattern. Despite the number of genres reduction in impacted locations, the expected richness expressed by the sum of the probability of genre occurrence in certain integrity value, is larger in preserved and degraded locations. Therefore, the genre substitution rate tends to be larger in very impacted and well preserved areas. The environmental matrix of the Cerrado is composed largely of already impacted areas, which explains this large number or genres that live in degraded locations thru simple area effect. Ultimately, we compared the results of two indexes used for ecological monitoring proposes of streams, that aim to observe different impacts in the environment. There was no relation between the Index of Habitat Integrity and an index that measures the pollution in the water (BMPW ), indicating that there is a need to use the two together for an effective monitoring.
Grupos substitutos, correspondência de assembléias aquáticas em relação a esquemas de classificação regional, e determinantes de diversidade beta em uma planície de inundação neotropical
(Universidade Federal de Goiás, 2010-01-25) PADIAL, André Andrian; BINI, Luis Mauricio; http://lattes.cnpq.br/0931860042124079
A general goal in community ecology is to understand how communities are organized in space and time. An aspect of great interest is to evaluate how concordant are the patterns of beta diversity depicted by different biological groups. If two taxonomic groups present a similar spatial/temporal structure, only one of these groups can be used as a surrogate group in conservation efforts or bioassessments. Also, a strong correspondence between biological groups and physical classifications of the habitat could help us to understand the reasons for spatial organization of communities. Moreover, if communities respond to a priori classifications based on geological and environmental features of the habitats, the selection of priority areas for conservation distributed on the classes of a classification scheme could maximize the conservation of overall biodiversity. Finally, to understand the main processes driving the organization of communities, the relative role of different set of predictor variables can be simultaneously evaluated. If species compositions are mainly predicted by environmental variables then one can conclude that species sorting mechanisms are the main drivers of community structure. On the other hand, if variables that represent spatial structure of the environments are the main predictors of variation in species composition, then neutral processes may be invoked to explain the structure of the biological group under analysis. Therefore, the main goals of this thesis are: (i) to evaluate the concordance among distinct biological groups; (ii) to evaluate the correspondence between a priori physical classifications of the habitat and the composition of assemblages and; (iii) to evaluate the relative role of environmental and spatial predictors on the structure of local assemblages in a Neotropical floodplain. For that, we used data sets on six biological groups (fish, benthic macroinvertebrates, aquatic macrophytes, zooplankton, phytoplankton, and periphyton) which were gathered during 2000 and 2001 in up to 36 aquatic environments of the Upper Paraná River floodplain. Patterns of assemblage concordance were frequently observed. The main mechanisms responsible for cross-taxon concordance were a similar response to environmental/spatial gradients and biological interactions between species. The mechanisms were identified after controlling for the effect of environmental/spatial variables on the cross-taxon concordance and after evaluating the level of concordance between species from each group that most likely are linked by biological interactions. However, the levels of assemblage concordance were weak and varied conspicuously with time. These results highlight that the use of surrogate groups is a flawed strategy to support conservation efforts in the Upper Paraná River floodplain. Nevertheless, the classification scheme of the floodplain, considering mainly limnological and geological aspects, was efficient to represent the structure of different aquatic assemblages. Thus, conservation efforts and bioassessments of the aquatic flora and fauna can use this classification scheme. However, the temporal variability also affected the consistency of the correspondence and this issue should be further investigated. On the other hand, temporal variables were not effective in predicting the structure of different biological assemblages. Environmental and spatial variables were generally more important, but also with low predictive power. Spatial variables were particularly important for large organisms with low dispersal ability, such as sedentary fish and aquatic plants. On the other hand, compared to spatial predictors, environmental variables were more important to explain the structure of small-bodied organisms with high dispersal ability (such as micro-algae) and organisms with migratory behavior. Nevertheless, all variables had a low predictive power, probably due to the low extent of the environmental and spatial gradients and to the lack of variables that represent relevant processes for determining the structure of aquatic assemblages in floodplains.
Macroecologia do zooplâncton continental: padrões latitudinais e componentes locais e regionais na determinação da diversidade global
(Universidade Federal de Goiás, 2012-02-13) PINESE, Olívia Penatti; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351
One of the oldest and best known global biological patterns in ecology is the latitudinal gradient of richness, characterized by a decrease in the number of species from Equator toward the poles. Several hypotheses, even today, attempt to explain the variation that occurs in the pattern of diversity of many animal and plants. Despite the advances that have been followed in Biogeography and Macroecology in recent decades, studies on biodiversity at a global scale have yet targeted mainly terrestrial and marine groups. This study presented three main objectives, first, to create a representative database of continental zooplankton diversity at global scale, that could demonstrate the distribution of richness patterns for their major groups (Total Zooplankton, Microcrustacea, Copepoda, Cladocera, Rotifera); second, to analyze the adequacy of global richness data to the Metabolic Theory of Ecology (MTE); and third, to establish the balance between local and regional components which determined the observed gradients. In this research, data collection was made from scientific papers concerning the diversity of continental zooplankton around the world. The sampling methodology effect on richness data was controlled through regressions, whose residuals were assumed as being the corrected richness. Latitudinal patterns analyses were performed with the corrected richness, developing latitudinal distribution graphs and global maps with color-weighted richness. The MTE was tested basically by analyzing the adequacy of the theory to angular coefficients, generated by multiple regressions between logarithm of raw richness, temperature (1/kT) and methodological variables. The contribution of local and regional components in determining richness was accessed through partial regressions. The results showed variation in the latitudinal patterns observed for different groups of zooplankton. Zooplanktonic crustaceans diversity peaked outside of Equator, while Rotifera diversity showed the classic latitudinal gradient, often found for many organisms around the world. Concerning the MTE, all groups showed different patterns from the one predicted by the theory. The local components were more crucial for crustaceans diversity while the regional components most strongly influenced total zooplankton richness and rotifers, which corroborates the observed results of latitudinal global patterns. This work represents a viable macroecological approach for access diversity patterns of biological groups whose taxonomic data and global geographical coverage about diversity knowledge are scarce, as they are for continental zooplankton organisms.
Avaliação de modelos de distribuição de espécies e sua aplicação na conservação da onça-pintada (Panthera onca)
(Universidade Federal de Goiás, 2010-11-19) TÔRRES, Natália Mundim; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351
Recently, Species Distribution Modelling (SDM) has been widely used as base for several types of analyses, including evaluations of climate changing impact on species distribution and conservation strategies settlement. This methodology enables the prediction of potential geographic distribution based on species ecological requirements, extrapolating data from known occurrences to unknown areas. There is a wide variety of methods which presents different capabilities to synthesize the significant relationships between species data and the environmental variables used as preditors. These variations are consequences of a series of factors that influence model s performance, such as species characteristics, the kind and quantity of data available, and the scale of the analyses. In this study we adopted the jaguar as a model to evaluate eleven SDM. It was evaluated the spatial autocorrelation effects between presence records on model s performance, and the relationship between environmental suitability obtained through these methods and jaguar population density. The obtained results were used as a basis for the evaluation of jaguar conservation topics, including analyses of how global climate changing and land use predictions will affect its distribution and evaluation of protected areas system in maintaining suitable areas for species occurrence in the future. It was demonstrated that depending on the model applied, the species data amount can be more influential than the spatial autocorrelation between presence points, and that the expected positive relationship between model-based suitability estimate and jaguar density was found only for four SDM, but always with a low coefficient of determination showing a weak data fitness. The analyses also showed that suitability values inside protected areas are greater than expected by null model, and this difference tend to increase with the global climate change scenario evaluated, demonstrating that it is not expected that environmental suitable areas for jaguars will shift out from the existing protected areas. Considering future predictions, the main conclusion is that some regions which must go through an environmental suitability increase for jaguar occurrence in the future will be converted from natural vegetation to agricultural land, indicating that the opportunities for jaguar s effective conservation actions are daily becoming more restricted, in such a way that the calling for a proactive conservation approach is urgent.

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