Programa de Pós-graduação em Ecologia e Evolução

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Análise da comunidade de peixes e da teia trófica de um trecho do rio corrente - go
(Universidade Federal de Goiás, 2006-07-18) ALOÍSIO, Gustavo Ribeiro; ANGELINI, Ronaldo; http://lattes.cnpq.br/6739463859587165
In this work, fishes of Corrente river, affluent of Paranaíba River (Paraná basin, Brazil), were studied. Five surveys in the period of June of 2003 had been carried out until June of 2005. The sampling was executed in 8 points distributed in the stream, riverbed and lagoon. In each point had been used a set of gillnets with different mesh size (between 12 and 60mm opposite knots). The nets were inspected in the morning and the end of the day. The results had shown that 8 species were captured and the most abundant specie is Astyanax altiparanae; Shannon-Wienner index demonstrated diversity low; Morisita index indicated that there are high similarity between river, stream and lagoons; all species reproduce in the rainy season with exception of the Brycon nattereri; it is demonstrated the existence of piscivores species, herbivores, insectivores and detritus feeders.
Estudo econômico-ecológico do Rio Araguaia pela demanda turística - Região de Aruanã
(Universidade Federal de Goiás, 2006-07-31) SANTOS, Manoel Eloy de Melo Oliveira dos; CARVALHO, Adriana Rosa; http://lattes.cnpq.br/1951710128353552
The Araguaia River has became one of the greatest point to the ecological tourism in Goiás region, due to its natural beauties such as beaches throughout its margins. The unplanned tourism may cause negative consequences to natural resources, thus to know the profile of the tourist and their knowledge concerning to the whole environment is an important tool into the ecosystem conservation. The Araguaia River is a food plain river, and it has several cities alongside the river, such as Aruanã, considered the entrance to Araguaia Valley. As many as 65% of tourists in Aruanã are men with mean age of 36 years old and married, with a high education degree and coming from Goiás. The tourists usually remain 10 days in Araguaia River spending an average of US$ 61,7 per day. The Araguaia River is the main attractive to 45,3% and fishing is preferred activity to relax to 24,2% of these tourists. Despite the tourist activity be quite connected to the ecosystem, the ecological wisdom of tourists about vegetation and ecological cycles are low, and 30% of them consider that they do use any natural resources, compromising the integrity of the ecosystem by the bad utilization of environmental services of Araguaia River, in Aruanã region.
Diversidade de morcegos (Mammalia: Chiroptera) em três sítios de cerrado da mineradora Anglo American em Niquelândia, estado de Goiás, Brasil
(Universidade Federal de Goiás, 2007-02-09) TOMAZ, Leonardo Aparecido Guimarães; ZORTÉA, Marlon; http://lattes.cnpq.br/8333704273610638
Bats were captured with mist-nets for 36 days along one year in the legal reserve of Anglo American Brasil/Codemin, in the municipality of Niquelândia, north of Goiás State. Three areas of three different fitofisionomias were inventoried: Dry Forest, cerrado and cerrado stricto sensu. Three expeditions were accomplished in the dry period and three in the rainy period during the new moon phase. Seven hundred and twenty-five bats belonging to nineteen species were recorded: Carollia perspicillata, Glossophaga soricina, Platyrrhinus lineatus, Pteronotus parnellii, Anoura geoffroyi, Desmodus rotundus, Molossops temminckii, Micronycteris minuta, Lonchophylla dekeyseri, Artibeus planirostris, Artibeus cinereus, Diphylla ecaudata, Platyrrhinus helleri, Lophostoma brasiliense, Artibeus concolor, Artibeus lituratus, Mimon bennettii, Phyllostomus discolor e Phyllostomus hastatus. The family Phyllostomidae represented 95,8% of the captures; the family Mormoopidae 3,0%, and Molossidae 1,2%. Carollia perspicillata was the dominant species (64,4%% of the sample) , followed for Glossophaga soricina (20%). The research still raised the presence of the one species threatened of extinction Lonchophylla dekeyseri. Artibeus concolor was recorded for the first time to Central Brasil. The Shannon-Wienner index (H') and Eqüitabilility (E) calculated for the areas it was: forest: H' = 0,716 E: 0,3260); cerrado area: H'=1,456 (E: 0,5677) and cerrado stricto sensu: H'=1,397 (E: 0,6068). The largest abundance was observed in the riverine forest (54,4%) and the largest number of species in the cerrado (13 species). Frugivorous species were predominantly in this study. The most similar areas were the two cerrado areas. It was observed a seasonal variation with relationship to the number of captures of bats, with a larger frequency observed in the rainy period. The three nectarivorous species found had picks of annual activities. The pattern of occurrence of species taxonomic or ecologically related revealed that P. lineatus and C. perspicillata didn't demonstrate correlation in the pattern occurrence (r = 0.72; p = 0,106) and a positive correlations were found for: M. minuta and M. temminckkii (r=0,917; p <0,05); M. minuta and P. parnellii (r=0,157; p=765); P. parnellii and M. temminckkii (r=-0,025; p=0,96). The study demonstrated that reserves legal of Anglo American Codemin it can be considered quite several when compared to other areas of Cerrado
Comunidade de algas perifíticas em substrato artificial no Rio Água Limpa e Lago dos Tigres (Britânia-GO) durante dois períodos de águas baixas
(Universidade Federal de Goiás, 2007-03-28) Rodrigues, Juliana; Nogueira, Ina de Souza; http://lattes.cnpq.br/3877834258990173; Nogueira, Ina de Souza; Kale, Valéria de Oliveira Fernandes; Oliveira, Leandro Gonçalves
Periphyton algae community on slides glasses at Água Limpa River and Lake of Tigres (Britânia, State of Goiás, Brazil) during two low waters periods. The aims of this dissertation was analyze the community of periphytic algae of Lake of Tigres (15°36"33,1''S/ 51º17'55,7''W) and Agua Limpa river (15°36"33,5''S / 51º17'56,3'' W ). Both environment belong the Tocantins-Araguaia basin and have differents water hydrodynamics. The first one is a blocked valley. This study looking for the influence of differents day of artificial substratum disposed in differents moths of low water periods (dry and beginning of the rain periods) in the first chapter and colonization during four weeks in dry period of 2005 in the second one. Were collected informations about climatic variables (temperature of air, pH, conductivity, turbidity, total dissolved solids, dissolved oxygen, total nitrogen and total phosphorous). The synthesis of limmnologicals variables was made by principal components analysis (PCA) and the synthesis of limnological and periphyton algae community were made by canonical correspondence analysis (CCA) and dissimilarity analysis (WPGMA) In the firs part of the study (2004) the artificial substratum were exposed during 20 until 37 days, both environments studied had high level of dissolved oxygen and water temperature, low level of nutrients and pH between alkaline and acid. Still had 67 taxa the majority was microperiphytics and ordinary species, high diversity and density tendency the β diversity had tendency to be homogeneous. The diatoms, R and S-selected taxa group were predominant in both sample stations. Only two species were dominant taxa (Navícula sp1- A1; Pinularia flexuosa - N2) and 34 were abundant. CCA characterized phosphorous and R-estratgist algae and Pseudoanabaena sp1, Surirella sp2, Oedogonium sp1, Cosmarium sp1, Cosmarium sp4 e Diploneis subovalis how the most important descriptors of the community of periphytic algae. In 2005, the artificial substratum that were exposed only in Agua Limpa River during four weeks and removed in 4th , 6th , 8th , 17th and 30th days, the water had high level of oxygen, nutrients and water temperature. Were registered 121 taxa, the majority micoperiphytic, ordinary species and diatoms. Were found high density and specific diversity. The β diversity was homogeneous specific composition, 72 abundant species, R and S-selected taxa group, and diatoms were representatives during the study, especially in richness and density. Both samples stations had same specific composition and functional group because de very closes geographic area. At the end of the study were detected the principal explanations of the periphyton algae community were made by R and S-selected taxa of functional group, Bacillariophyceae, high diversity and density and Total phosphorous.
Suficiência taxonômica, resolução numérica e grupos substitutos: uma análise para a comunidade fitoplanctônica de ambiente lótico
(Universidade Federal de Goiás, 2007-12-11) CARNEIRO, Fernanda Melo; BINI, Luis Mauricio; http://lattes.cnpq.br/0931860042124079
Classification systems are necessary to organize the huge complexity of biological systems. Frequently, these systems are useful to studies focusing on environmental monitoring, conservation plans and biodiversity assessments. Studies on phytoplankton ecology are, in general, conducted with the identification of organisms up to the species level. This is a costly, laborious and complex task that demands experienced biologists. However, for some purposes, higher taxonomic levels may be enough, mainly when main trends are identified by either data at low or higher resolution (taxonomic and numeric). In this study, it was evaluated if the temporal trajectories described by a lotic phytoplankton community, which were first summarized by an ordination technique, were dependent or not on the taxonomic/numerical resolution used to represent the data. The phytoplankton classification system in functional groups was also contrasted against simple taxonomic classifications in order to verify if they really offer distinct patterns of ordination. Procrustean analyses indicated that patterns of ordination generated by incidence data of genus were significantly concordant with the patterns generated by density of species. Temporal trajectories of scores derived from functional groups significantly matched those derived from analyses based on the quantitative data (density or biovolume) of genus or family. Thus, at least for the system investigated here, the complexities associated with this classification criterion may be unwarranted. In general, the results indicated that some simplifications were justifiable, mainly when one takes into account the need of uninterrupted biomonitoring programs over large spatial scales in a continental-sized country, with increasing environmental problems, and with a paucity of scientists
Seleção de áreas prioritárias para conservação da diversidade genética para alvos múltiplos
(Universidade Federal de Goiás, 2008-02-01) PADUA, Gabriela Cristina Cantisani; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351
Rapid urban development, due to population and economic growth, results in largescale changes in landscape. As a consequence, there is a massive extinction of species. That s why identifying networks of important areas for conserving biodiversity is important and should provide a better currency for biodiversity conservation than just keep species in isolated areas. Until recently, the methods for identifying networks for biodiversity conservation have not deal explicitly and directly with the goal of evolutionary persistence of species. Trying to achieve the adaptative diversity of each specie, data about the genetic variation of species has been incorporated into the broadscale reserve network model. Populational genetic structure and geographic range size of multiple species data were used in a reserve network plan and compared with a reserve plan that uses only ecological data such as geographic range size. The genetic variation was determined based on papers found at Institute for Scientific Information (ISI). It has been shown that when used, genetic variability data, change the location of the spatial configuration of important areas for biodiversity conservation. Concluding that genetic information is important and relevant when associated with geographical distribution, what can improve species evolutionary persistence
Estudo sobre o comportamento de apetência de diferentes estágios do carrapato Amblyomma cajennense (Acari: Ixoidae)
(Universidade Federal de Goiás, 2008-02-25) ASSAL, Flávio Ezzeddine El; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648; BORGES, Lígia Miranda Ferreira; http://lattes.cnpq.br/2591106734434348
This paper evaluates the behavior of appetite expressed in different stages of the ticks Amblyomma cajennense testing the hypothesis that nymphs and adults of this species have strategy of game play while the larvae ambush. To this end, through observations, we sought to describe and propose a classification of appetite expressed by these different stages comparing strategies appetite displayed by different instars of the species with the express adult Rhipicephalus sanguineus on the same environmental conditions. Experimentally, the expressions of these behaviors face of different stimuli (CO2, equine odor, shading, radiant heat, and the 'air control') were evaluated. For this, we collected ticks of the species in horses and dogs naturally infested Center for Zoonosis Control in Goiânia-GO, which were created in rabbits and multiplied in the vivarium of the Center for Veterinary Parasitology, Federal University of Goiás (CPV / UFG ). The ratings of the behaviors that occurred in a room of the Centre -CPV/UFG were held in a glass box with removable cover, having a dozen plastic rods for the expression of search strategies. This glass chamber showed temperature conditions (25 º C + / -3 ° C), relative humidity (80%
Transformando tropeços em passos de dança: o uso de espécies exóticas para estudos biogeográficos
(Universidade Federal de Goiás, 2008-02-27) LIMA JUNIOR, Dilermando Pereira; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351
The establishment of exotic species is known for the negative impacts it causes. However, it can be used as models to study the ecological and evolutionary causes of biogeography patterns and access whether the niche conservatism is the determinant of the species limits distribution. The main purpose of this study is to evaluate the difference between pools of exotic fish species in biogeographical regions of the world based on the theories of Niche Conservatism and Evolutionary Dynamics of Latitudinal Gradients of Diversity. We found a strong tendency of the niche conservatism with exotic fishes, but no phylogentic structures of the invaders fishes were found. Therefore, predictive models that purpose to evaluate the potential invasion of fishes has to, include extrinsic factors as climatic conditions, propagule pressure, environmental disturbance, human use and intrinsic factors as parental care and body size of the species.
Biogeografia da conservação de morcegos no cerrado brasileiro
(Universidade Federal de Goiás, 2008-06-06) Barreto, Bruno de Souza; Bini, Luis Mauricio; http://lattes.cnpq.br/0931860042124079
The units of conservation are main strategy adopted by the rulers to guarantee that the negative effects of the socioeconomic development reach less the biodiversity. recent researches have been trying to outline the problem through reserve selection that seek larger representativeness of the goals of conservation (in general some estimador of the biodiversity as the species) in terms of a smaller number of areas as possible. in the last 50 years the cerrado is going by transformations in their natural landscapes due to the progress of the modern agriculture and of the livestock. due to that, the objective of that work was to define priority areas network for conservation of bats in terms of five conservation sceneries differents. the generated nets were restricted by socioeconomic cost, presence of cave and a cost that considers the previous two cost. the results revealed main features of analyses of complementarity: multiple solutions, flexibility of the nets, and influence of the rarity of the species for the definition of groups starting from the pattern of rarity. the costs were important for definition of nets that avoided as much conflicts of conservation as prioritized the species in areas of cave.
Ecologia reprodutiva de Hypsiboas albopunctatus (Spix 1824) (Anura, Hylidae), no município de Cocalzinho de Goiás, leste do estado de Goiás
(Universidade Federal de Goiás, 2008-06-27) Santos, Marcela Peixoto dos; Bastos, Rogério Pereira; http://lattes.cnpq.br/6015137404238990
(Sem resumo em outra língua)
Variação Temporal da Atividade de Forrageio de Cupins (Insecta, Isoptera) sobre Iscas de Papel Higiênico em Hidrolândia, Goiás
(Universidade Federal de Goiás, 2008-09-29) SANTOS, Thiago; BRANDÃO, Divino; http://lattes.cnpq.br/1614480825290154
Termites are social insects with 2800 described species which feeds on cellulose in different stages of decomposition. Based on the proportion of organic matter found in there gut content they are classified in four feeding groups: group I (not Termitidae), dead wood and grass feeders; group II, Termitidae that feeds on same food source that of the group I; group III, which feed on decomposed wood and organic matter rich soil; group IV, true soil feeders. The foraging activity is subject to a trade-off: the adverse weather conditions of the dry season impose physiological limits, but the colonies need a large quantity of food during this season to meet the needs of alates production for the next swarming period. The objective was to verify if the termite community in an area of forest and savannah of the Cerrados presents changes in the activity of foraging between the dry and wet season of 2007. The study was conducted in the municipality of Hidrolândia-GO at RPPN "Banana Menina" (16º57"44'S and 49º13"41'O). The climate of the region is the type Aw of Köppen. Six grids with 20 baits consisting of a roll of toilet paper away from adjacents 1m and buried at a depth average of 3cm were mounted in the two physiognomic forms. Each grid was placed at a distance of at least 100 m from the others. The collections were made on Sundays during two months after the baits installation, totaling eight collections each season (July and August in the dry season and November and December in the wet season). It was found 28 species of termites, 24 in the dry season, of which 11 in the forest physiognomy and 16 in the savannah. In the period of rain, 19 species were sampled, with 11 at the forest and 11 at the savannah. All feeding groups were collected in all seasons and physiognomies, with the exception of group IV, which occurred only in the savannah. Group II was the richest with 13 species and group I, even showing the slightest specie richness (3 species), occupied the largest number of baits (47.6 and 10.25 in the rain and the dry seasons respectively).Considering the entire termite community a significant increase in the number of baits attacked in the rainy season was verified and this trend was similar in both physiognomies. Only the group I has show a significant difference in the number of baits occupied between the two sample period, with no interaction between physiognomy and season. The most abundant species were Heterotermes tenuis (feeding group I) and Velocitermes velox (feeding group II), present in both physiognomies, Cornitermes snyderi (feeding group II) and Nasutitermes cf. jaraguae (feeding group II), present only in the savannah and Neocapritermes opacus (food group III) and Heterotermes longiceps (food group I) present only in the forest. N. opacus and C. snyderi increased significantly the number of baits occupied in the rainy season. The other species did not show any change. The activity of foraging termites in the area of studies presented a peak during the rain season. The colonies are subject to different pressures due to its characteristics as period of swarm, population dynamics, body size, feeding group and type and location of nesting and foraging.
Estrutura espacial da assembleia de cupins (Isoptera) em uma área de cerrado sensu stricto do Parque Estadual da Serra de Caldas Novas, Goiás
(Universidade Federal de Goiás, 2009-01-30) OLIVEIRA, Danilo Elias de; BRANDÃO, Divino; http://lattes.cnpq.br/1614480825290154
One of the major community ecology's objectives is to understand the factors that determine the spatial distribution of populations of different species belonging to an assembly. Works that investigate these causal factors on the termite fauna are rare, and to the Cerrado region, non-existent. This work aims to 1) describe the spatial structure of the termite assembly in a cerrado sensu stricto area, 2) verify whether there is spatial autocorrelation in the composition of termites and 3) whether the species are distributed on a checkerboard, and if so, what cause this distribution. On the plateau of Parque Estadual da Serra de Caldas Novas (PESCAN), I sampled the termites on 123 10m2 plots with distances to each other varying from 5 m to 3.5 km. This plots were divided into two sets, One of those arranged into 3 transects of 28 plots each and the other arranged into 13 triads distant 1 km to the next. I Identified the species and grouped them into food guilds. I made a Mantel s autocorrelogram with 10 distance classes to assess the changes in the similarity of the composition in function of space. I compared the C-score index, using the entire assembly and each guild alone, with a null distribution (with 5000 randomizations) to check whether there is a checkerboard distribution in the assembly and what its cause. I found 579 colonies of 57 species of termites, most of which was humivorous. There was no significant spatial autocorrelation in any distance class concerning the species composition because the values of r of Mantel for all distance classes were close to zero and not significant. The C-score was significant for the assembly as a whole (C-score = 52.01, p = 0.006), but was not significant for any of the guilds. The cerrado of PESCAN is one of the areas with the highest species diversity already registered for the Cerrado biome and possibly this is because of the well preserved condition of the park and the sampling effort employed. The absence of spatial autocorrelation indicates that the species of termites are distributed in space regardless of the distribution of others. This is the first study that shows that the assembly of termites is distributed on a checkerboard and that this is due to historical events of dispersal and colonization. In the area I studied, probably the dispersion of the allates during flight events makes the establishment of future colonies in a field forming a "scrambled" and not superimposed distribution known as checkerboard distribution. These results contradict the recurrent idea that intra and interspecific competition is the causal factor of the colonies spatial distribution of termites.
Efeitos de borda sobre comunidades de musgos (Bryophyta) epifíticos em área de Cerrado no Brasil Central
(Universidade Federal de Goiás, 2009-02-24) CARVALHO, Maria Adriana Santos; GUILHERME, Frederico Augusto Guimaraes; http://lattes.cnpq.br/6514433986706275
Microclimatic changes enhanced by the proliferation of edges in fragmented landscapes, known as "edge effects" may result on shifts in species composition, structure of communities and ecological processes. Despite the dramatic increase in edge areas caused by anthropogenic habitat fragmentation, the edges and their areas of influence is a relevant structural feature also in the natural landscape. This is evident in the Cerrado biome, which is suffering an accelerated degradation and habitat loss and is composed of mosaics of vegetation types which are common boundaries or ecotones. The bryophytes are an ideal group for assess the edge effects because are vulnerable to microclimatic changes promoted by their physiological conditions, making them particularly useful as indicators of the adverse fragmentation effects. Thus, this study aimed to assess how the communities of epiphytes mosses (Bryophyta) respond to forest edges originated of anthropogenic fragmentation and the natural edges in the grassland-forest transitions in the Cerrado. The study areas are located in the Parque Estadual da Serra de Caldas Novas and its surroundings, including municipalities of Caldas Novas and Rio Quente, state of Goiás. Sampling was done in three habitat types: (1) gallery forests on the slopes of the mountain with abrupt transitions to rock outcrops fields, (2) edge (0 to 10 m) and (3) interior (100 to 110 m) of seasonal forest fragments surrounded by a matrix of grazing. These were the three treatments considered in the analysis, described by the abbreviations: BN (natural edge), BA (anthropogenic edge) and IF (interior of the fragment). For each treatment four replicates were selected. Four plots (10´10m) were randomly delimited along transects (10´200m) for each treatment in each area. For the sampling of mosses in the plots, were selected all trees with perimeter at breast height (PBH) ≥ 20 cm and with minimum bryophytes coverage of 300cm2. For the quantitative survey of mosses was employed the interception line method. The comparison of Jackknife richness estimates (33.56 to IF, 30.56 to BA and 25.63 to BN) showed that there were differences between IF and BN. The coverage of mosses was significantly higher in BN than in BA (F2,45 = 5.34, p = 0.008). The analysis of similarities (ANOSIM) showed that the community of mosses was more distinct in BN, and the composition of species in this environment was significantly dissimilar to BA in IF (R = 0.198, p < 0001). Two factors may explain the fact that the edge effect on species richness and coverage of epiphytic mosses has not been shown in this study: (1) The homogeneity of the vegetation structure observed between edge and interior and (2) the fact that the study had considered only the mosses, 8 whereas many studies confirm a higher sensitivity to disturbance of the liverworts. Clearer effects were observed between BA and BN, both in coverage and in species composition, which is probably due to differences in spatial and temporal development of these edges, or topographic features of the gallery forests, particularly the fact of being located in depressions with creeks, which probably provides more moisture in these environments. The chi-square test showed significant differences in the frequency of occurrence of life forms in the different treatments, except for the tuft form. The greatest value of chi-square occurred to the flabelliform life form, which predominated in BN, collaborating with the evidence already presented of microclimatic conditions more favorable to mosses in BN, since the flabelliform habit are intolerant to desiccation. This indicates that the use of functional groups of bryophytes, such as life forms can generate more generalization and get clearer answers than species richness in the evaluation of the edge effects.
A utilização da paisagem fragmentada por mamíferos de médio e grande porte e sua relação com a massa corporal na região do entorno de Aruanã, Goiás
(Universidade Federal de Goiás, 2009-02-25) CALAÇA, Analice Maria; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648; MELO, Fabiano Rodrigues de; http://lattes.cnpq.br/6863533704023271
The species are behaving differently to the process of fragmentation and this behavior will depend on the relationship between behavioral, morphological and ecological traits with the physical attributes of the landscape. The body size is a major ecological factors and some links are made between the size and dispersal ability, capacity for perception of the environment and likelihood of occurrence. In this way, the objective was evaluate as is the distribution of mammals in fragmented landscape of Aruanã, Goiás, Brazil testing the following hypotheses: 1) Fragments larger and less isolated have high species richness, 2) species of greater body mass are less affected by fragmentation due to greater dispersal ability; 3) species of greater body mass are distributed more homogeneous in the landscape. We recorded 19 species of mammals, the area but not isolation, was a significant predictor to explain variation in species richness of mammals with larger areas being richer than smaller areas. Large species like jaguar and puma, red brocket deer and gray brocket deer, collared peccary, ocelot and agouti were sensitive to the effect of the area and therefore the effect of fragmentation, which is not confirmed the second hypothesis. However, these species were not restricted only to larger areas, being found also in small fragments used as a temporary source of resources. The puma was the only species that showed significant incidence-isolation relationships. There was no pattern of a homogeneous distribution for these species, but for the tapir, with higher body mass recorded, the results were exactly the opposite of what was observed. The minimum area estimated that 50% or more of the populations of sensitive species occurs in fragmented landscape was 520 hectares. These results reinforce the importance of maintaining forest fragments, almost all belonging to private lands in the conservation of species.
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.
Orchidaceae do Parque Estadual da Serra de Caldas Novas, Goiás, Brasil
(Universidade Federal de Goiás, 2009-03-31) HALL, Climbiê Ferreira; KLEIN, Vera Lúcia Gomes; http://lattes.cnpq.br/6477452328378345
(Orchidaceae of the State Park of Serra de Caldas Novas, Goiás State, Brazil). This study conducted a survey of the Orchidaceae species occurring at State Park of Serra de Caldas Novas (PESCAN) and a study of the floral biology and reproductive biology of Cyrtopodium eugenii Rchb. f. & Warm. and the effect of floral herbivory on reproductive success of this specie that occurs in the rocky fields of PESCAN. The Orchidaceae family consists of 850 genera, with about 20000 species, and has cosmopolitan distribution, but its greatest concentration is in the tropical region. In Brazil, 200 genera are found, with more than 2500 species, and then, it is considered the third country in the world in diversity of orchids, only inferior to Ecuador and Colombia. In the Cerrado Biome, the family is represented by 666 species, from these, 12 species and 7 genera were found in PESCAN. The most common habit among the species that occur in PESCAN is the terrestrial and the predominant flowering season is the rainy season. Only one specie flowers in the dry season, C. eugenii, a common specie in PESCAN, which flowers from May to September. Cyrtopodium eugenii flowers are pale-yellow with brown spots, but the lip is bright-yellow. The only species found as a pollinator of C. eugenii was Centris (Trachina) fuscata Lepeletier,1841 (Anthophoridae, Centridini). Although C. eugenii offers no floral rewards to pollinators, its lip seems to mimic flowers of Tetrapterys ramiflora A. Juss., a yellow-flowered oil producer Malpighiaceae. Thereby, C. eugenii deceives the pollinator. As in other species without reward, C. eugenii receives few visits from their pollinator, and consequently has a low fruit production rate. Cyrtopodium eugenii is self-compatible, but no fruit was generated by spontaneous self-pollination as well as agamospermy. Preliminary field observations revealed that inflorescences and flowers of C. eugenii experience continuous florivory. The natural florivory quantification shows that 55.20% of the flowers weren t eaten,while in 15.45% sexual structures were eaten (florivory direct effect). More flowers had the lip damaged (20.50%) than the other petals and sepals (18.92%). A manipulative experiment showed a significant decrease in C. eugenii reproductive success (male and female), only if the florivory occurred in the lip (florivory indirect effects). This result indicates that the lip is the most important flower part to attract the pollinator and to C. eugenii reproduction, because even with a high level of herbivory in the other petals and sepals, the reproductive success didn t decay significantly.
A Teoria Neutra pode explicar a diversidade de insetos aquáticos em riachos?
(Universidade Federal de Goiás, 2009-04-07) ALMEIDA, Mirian Cristina de; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648
The generality of Unified Neutral Theory of Biodiversity and Biogeography was evaluated across its support for diversity structure of Odonata adults and predators, shredders and collectors insect guilds in streams. The evaluation of Neutral Theory was done in two levels of theory s hierarchical structure. One evaluation in the level of yours assumptions, the zero sum assumption, and other in the level of yours predictions to abundance models in communities and metacommunities, ZSM and logseries respectively. The variations predicted to ZSM abundance model, in accordance to dispersal limitation that community are subjected, was evaluated in insect guilds through the streams distance. In Odonata adults the dispersal limitation was evaluated indirectly through regional frequency of species body size. In this case, the ecological equivalence was restricted for body size guilds. Communities of Zygoptera adults have low density and richness within streams. Individuals distribution was grouped, not consistent to linear relation under zero sum assumption. Local abundance of Odonata adults and predators, shredders and collectors guilds didn t fit ZSM model. Geometric series models and logseries models were better in explain the abundance for all groups. Moreover, the occurrence of fit to these models isn t in according to dispersal limitation level that is expected in each region, not supporting the Neutral predictions
Evidências experimentais para a associação entre o nível de relação filogenética e a intensidade de competição entre espécies de gramíneas exóticas e nativa
(Universidade Federal de Goiás, 2009-06-05) AZEVEDO, Rodrigo Carvalho de; PORTES, Tómas de Aquino; Tómas de Aquino Portes; BINI, Luis Mauricio; http://lattes.cnpq.br/0931860042124079
Biological invasions has been a major threat to whole biomes around the world, affecting communities and ecossistems with consequences to the trophic web. At the same time it is a huge biogeographical experiment that allows the formulation of hypotheses about the rules for communitie assembly. This study tested the hypothesis that the level of phylogenetic relationship is positively correlated with the magnitude of competitive interactions, being stronger for closer species. We used two exotic African species (Panicum maximum and Andropogon gayanus) and a native of South America (Paspalum atratum-focal species) in a partial additive design for the mix of native-exotic, with an increase in density of the exotic. The results showed greater competitive effect on the focal species when in the presence of P. maximum (closer to the focal), suggesting that predictions can be made on potential invasive species based on the Darwin s Naturalization Hypothesys.
Componentes geográfico, ecológicos e evolutivos do nicho das espécies de carnívoros (Carnivora: Mammalia) do Novo Mundo
(Universidade Federal de Goiás, 2009-06-22) CRUZ, Mary Joyce Ribeiro da; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351
The questions around species niche have sought to unveil why a species is where it is and it is not where it is not, so it is well known that a lot of factors can be determinant in this discussion. Thus, in this study we examined the relationship between niche and geographical distance, life history and phylogenetic components to the New World carnivores. The data used in our analyses were obtained from datasets available online and from literature sources. We used Mantel s test to evaluate the correlation among the data matrices in NTSys software. Significant correlations were found between niche and geographical distance (r =-0,4068 e P <0,0001) and between life history and geographical distance (r = -0,1136 e P= 0,0024). These results suggest that species that are spatially close are more similar in terms of niche and life history. We also observed that, among others factors, interespecific interactions has an important effect in structuring ecological communities. New tests are still necessary in future to generate new information about carnivore s niche and their components.
Estrutura em comunidades de insetos aquáticos: uma abordagem experimental em córregos no município de Niquelândia, Goiás, Brasil
(Universidade Federal de Goiás, 2009-09-23) Jesus, Jhonathan Diego Nascimento de; Oliveira, Leandro Gonçalves; http://lattes.cnpq.br/4995825091971711; Brandão, Divino; Oliveira, Leandro Gonçalves; Pereira, Marcos Callisto de Faria; Oliveira, Leandro Gonçalves
A broad spectrum of abiotic and biotic factors influences the structure community of aquatic insects. This study was conducted in five intermittent streams in the city of Niquelândia in the State of Goiás, on area of influence of mining company Anglo/CODEMIN, near Serra da Mesa Lake. The material used to construct the artificial substrate was one kilogram of crushed rock (gneiss) surrounded by rings of nylon mesh 0.5 mm, due to the similarity of this material to the natural substrates in sampled streams, formed mostly by stones. Five samples were placed in each stream arranged with the average distance 1 meter between them. The samples were placed in sampling points after the first rain event in the region, since all the streams used in the experiment were dry. Every seven days a sample was withdrawn and replaced by another that remained in streams only seven days. The others remained fourteen, twenty-one, twenty-eight and thirty-five days. The result of quadratic polynomial regression showed a structuring related to the sites sampled and Lake Serra da Mesa, only the second ANCOVA results showed, suggesting a significant community structure analyzed by dominance, although that this arrangement has been low. Thus, was observed that the community addressed were more structured by abiotic factors versus the initial hypothesis that predicted a structure based on patterns of dominance and founder effect, concludes that in early stages of colonization succession the factors that can improve the structure of communities are the abiotic ones.

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