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Item 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/1614480825290154One 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.Item 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/1614480825290154Termites 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.