A queima prévia ao corte dos canaviais causa uma série de inconvenientes ao meio ambiente e em particular à entomofauna associada à cultura. O fogo é largamente usado no controle de pragas e doenças na agricultura, entretanto seu efeito sobre populações de insetos não é bem entendido ou documentado, principalmente sobre grupos de invertebrados que são responsáveis pela ciclagem de nutrientes e fluxo de energia. Assim sendo, o objetivo deste trabalho foi avaliar o efeito da queima controlada da palhada da cana-de-açúcar sobre a comunidade de insetos locais. Os insetos foram coletados em diferentes datas antes e após a queima. Dos 35 taxa coletados, 17 foram considerados mais relevantes para explicar a variação observada da freqüência de captura das espécies ao longo do tempo. Na primeira coleta depois da queima, verificou-se a redução do número de insetos em cinco espécies [Nitidulidae (espécie 2; Coleoptera), Lutosa brasiliensis (Brunner von Watternwyl)(Orthoptera: Gryllacrididae), Phoridae e Drosophilidae (Diptera) e Labia minor L.(Dermaptera: Labiidae)], dentre as 17 selecionadas para análise. A análise de variáveis canônicas para as diferentes datas de coleta indicou diferenças significativas entre os tratamentos, considerando a composição e a abundância das espécies. Apesar da diferente composição da comunidade de insetos observados antes e após a queima, os dados apresentados sugerem uma tendência de recuperação da comunidade ao padrão observado antes da queima.

The previous burning of sugarcane straw before harvest causes a series of inconvenients to the environment, specially to the tillage-associated insects. Fire is used to control pests and diseases in the agriculture, however its effect on insect populations is not well understood or documented, mainly on invertebrate groups responsible for nutrient recycling and energy flow. Our objective was to evaluate the effect of controlled burning sugarcane straw on the local insect community. The insects were collected in different dates before and after burning. The species selected for the analysis were affected by fire. Among the 35 taxa collected, 17 were considered more relevant to explain the observed variation in the frequency of species captured through time. In the first sampling after burning, there was a decrease in abundance of five species [Nitidulidae (species 2; Coleoptera), Lutosa brasiliensis (Brunner von Watternwyl) (Orthoptera: Gryllacrididae), Phoridae e Drosophilidae (Diptera) e Labia minor L. (Dermaptera: Labiidae)], among the 17 species selected for analysis. The canonical variate analysis for different sampling dates indicated significant difference between treatments, considering the composition and the species abundance. Despite the different composition of the insect community observed before and after burning, there is a tendency of community recovery to the observed pattern before burning.

Queimadas de baixas intensidades podem promover sensíveis alterações nas propriedades físicas, químicas e microbiológicas do solo, na profundidade onde se estabelecem os sauveiros iniciais de Atta Fabricius. Considerando que o estabelecimento da nova colônia é o período mais crucial da vida da colônia, investigaram-se neste trabalho as implicações pós-fogo de uma queima controlada de palhiço de cana-de-açúcar de intensidade igual a 615 kJ. m-1.s-1 na escolha de locais para escavação dos ninhos e estabelecimento inicial de colônias de Atta bisphaerica Forel. A queima eliminou matéria orgânica superficial da área, o que implicou em aumento significativo de densidade até a profundidade de 15 cm. Da mesma forma, a eliminação da vegetação pelo fogo promoveu maior resistência do solo à penetração. Essas alterações nas propriedades físicas não afetaram significativamente a escavação dos ninhos iniciais por fêmeas de A. bisphaerica e nem tampouco influenciaram a profundidade de construção de suas câmaras iniciais em condições de laboratório. A queima alterou a constituição química do solo e promoveu alterações na atividade microbiológica do mesmo. Em condições de campo, as fêmeas de A. biphaerica apresentaram maior taxa de estabelecimento em locais queimados. Em condições de laboratório, colônias cujas fêmeas estabeleceram-se em solos provenientes de áreas queimadas apresentaram maior mortalidade do que aquelas estabelecidas em solos de áreas não queimadas.

Even low intensity fires may often modify the chemical, physical and microbiological properties of the soil, in the depth where leaf-cutting ants Atta Fabricius establish their nests. Considering that nest foundation and establishment are the most crucial steps in a colony life cycle, this research investigated the implication that a controlled 615 kJ.m-1s-1 fire intensity of sugar cane dry foliage have on the nesting of Atta bisphaerica Forel. Burning eliminated organic matter from the soil surface; this resulted in a significant increase on its density down to a depth of 15 cm. The elimination of vegetation by fire also increased soil resistance to penetration. These alterations on physical properties had no significant effect on the depth of initial A. bisphaerica chambers under field and laboratory conditions. Burnings did affect soil chemical and microbiological properties. A. bisphaerica females looked for sites which had been burned to establish their colonies in the field. Under laboratory conditions, the mortality of colonies was higher in soil originating from burned areas than unburned ones.

Here is described the diet of Proceratophrys boiei (Wied, 1825), a leaf litter frog of the Atlantic Forest, and test for relationships between frog size and prey size and type. The diet was determined by stomach content analysis. In 38 frogs, was found 76 prey items belonging to 23 taxa. Insects predominate in the diet and the most frequent categories were coleopterans (39.4% of total volume) and orthopterans (25.0%). There was a positive correlation between frog size and volume of prey taken. The most important ontogenetic shift in prey type was an increase in the consume of coleopterans and insect larvae with increasing frog size.

The nesting habits of the leaf-cutter ant Acromyrmex laticeps nigrosetosus Forel were studied in areas under Eucalyptus plantations in Minas Gerais State, Brazil. A total of 12 nests were killed with methyl bromide and talcum was injected into entrance holes with a small air pump to mark the underground chambers and channels. In general, these nests presented a single chamber with average dimensions of 0.28 x 0.23 x 0.19 m (length x width x height) located just below the soil surface (0.11 m). Chambers were connected to the soil surface by 2-5 channels which opened at the surface. Externally they were covered by a large amount of dry leaves and in their early stage presented a mound of loose soil. The total nest population was, on average, 12,231 individuais. To our knowledge, this is the 1st description of this species' nests in Minas Gerais State.

It was sampled the litter frogs at altitudinal sites of a semideciduous mesophytic forest located at Sena do Japi (Jundiaí, São Paulo, 23º17'S, 47º00'W, 800-1300m altitude, 1500mm rain/year). Forty two plots of 8x8m were sampled in the dry/cold season of 1995: 21 at a Higher Site (HS) (1000m) and 21 at a Lower Site (LS) (850m). The plots were evenly located near, mid-distance, and far from the stream-bed. It was found a total of five species, three at each site. Eleutherodactylus guentheri comprised 83% of the individuals at HS and E. juipoca 67% at LS. The density of individuals was higher at HS and near the stream. The greater density at HS may be due to greater humidity there, provided by mist. The frogs may aggregate in wetter places (stream edges) in the dry/cold season. The studied sites represent harsh and early successional environments and both these factors may be acting together to produce the low observed diversity.

This Work was conducted in Eucalyptus stands at the Itapoã farm of the Mannesmann Fi-El Florestal Ltda. in Paraopeba, MG. The species of fungus growing-ants and leaf-cutting ants found in regrowth areas and in harvesting phase plantings were: Acromyrmex balzani Emery, 1890; Acromyrmex laticeps nigrosetosus Forel 1908; Acromyrmex subterraneus subterraneus Forel, 1893; Atta laevigala (F. Smith, 1858); Alta sexdens rubropilosa Forel, 1908; Mycocepurus goeldii Forel, 1893; Sericomyrmex sp.; Trachymyrmex fuscus Emery, 1894 and three morphospecies of Trachymyrmex Forel, 1893. Taxa belonging to the genus Atta Fabricius, 1804 represented 39.14 and 41.22% of the total number of nests found in the regrowth area and in the harvesting phase plantings, respectively. For Acromyrmex Mayr, 1865 these values were 14.34 and 13.16%; for Trachymyrmex, 40.59 and 30.89%; for Mycocepurus Forel, 1893, 5.34 and 12.50% and Sericomyrmex Mayr, 1865, 0.59 and 2.23% in the regrowth area and in the harvesting phase plantations, respectively.