ABSTRACT Although dung beetles are important members of ecological communities and indicators of ecosystem quality, species diversity, and how it varies over space and habitat types, remains poorly understood in the Brazilian Cerrado. We compared dung beetle communities among plant formations in the Serra Azul State Park (SASP) in the state of Mato Grosso, Brazil. Sampling (by baited pitfall and flight-interception traps) was carried out in 2012 in the Park in four habitat types: two different savanna formations (typical and open) and two forest formations (seasonally deciduous and gallery). A total of 5,400 individuals collected comprised 57 species in 22 genera. Typical savanna had the greatest species richness and abundance, followed by open savanna and deciduous forest, while the gallery forest had the fewest species but high abundance. Tunnelers (one of three main nesting behavior guilds) showed the greatest richness and abundance (except in the gallery forest, where one dweller species was extremely abundant) in all plant formations. We found that species richness and abundance of the dung beetle community are influenced by differences among plant formations. Habitat heterogeneity in the different plant formations along with anthropic influences (fire, habitat fragmentation) are cited as important factors that explain guild and species richness and distribution patterns. These results emphasize the importance of protected areas, such as SASP, for the maintenance and conservation of species diversity in the Brazilian Cerrado.

Abstract A greater number of structures are being built with flat reinforced concrete slabs because they offer several advantages. However, many designers are still unsure about the type of slab that has the best structural performance and which building codes provide the best strength estimates. This study presents nonlinear computer simulations of 16 flat reinforced concrete slabs under symmetrical punching: 4 solid slabs, 4 waffle slabs with wide beams, and 8 waffle slabs with different numbers of ribs supported in the solid area of the slab. Geometric longitudinal reinforcement ratios ranged from 0.45% to 1.97%. The results showed that solid and beamed slabs are more resistant, and normative estimates overestimate their strengths, while the opposite outcome was found for waffle slabs, whose estimates provided in the codes were rather conservative. The most accurate code was EC2, followed by ACI 318 and NBR 6118.

Os besouros rola-bostas são insetos copro-necrófagos e utilizam primariamente fezes e carcaça de mamíferos como fonte de alimento e nidificação. Estes insetos são sensíveis à modificação do habitat principalmente relacionados à cobertura da vegetação. A substituição da floresta Amazônica por pastagem altera drasticamente o habitat das espécies nativas e acarreta redução da riqueza de espécies e modificação na composição das assembleias locais. O objetivo deste trabalho foi compreender os efeitos da substituição da floresta nativa por pastagem introduzida na riqueza, abundância, composição de espécies e estrutura das guildas alimentares dos besouros rola-bostas no sudoeste da Amazônia brasileira. Foram coletados 10.073 indivíduos de besouros rola-bostas pertencentes a 84 espécies e 22 gêneros. As florestas (seis fragmentos de floresta secundária) apresentaram 71 espécies em sua maioria com abundância intermediária. As pastagens (áreas vizinhas onde a floresta original foi substituída por pastagens introduzidas) apresentaram redução significativa no número de espécies, e composição de espécies diferente. Nas florestas a maioria das espécies foi considerada generalista, enquanto as pastagens apresentaram maior abundância de espécies coprófagas o que demonstra uma modificação na guilda alimentar causado pela substituição da floresta por pastagem. Entre as 30 espécies coletadas nas pastagens, doze estão presentes em vegetação aberta nativa (cerrado e chaco). Isto retrata, provavelmente, um processo de colonização regional recente. Onde espécies de besouros rola-bostas, oriundas de áreas abertas, estão invadindo as pastagens amazônicas.

The dung beetles are copro-necrophagous insects and use mainly feces and carrion of mammals as food and nesting source. These insects are sensitive to habitat modification mainly related to vegetation cover. The substitution of the Amazon forest by pasture cause drastic changes in the habitat of native species. This reduces richness and modifies assembly species composition. The aim of this work was understand the effects of substitution of native forest by pasture introduced in richness, abundance, species composition and structure of feeding guilds of dung beetle in southwestern Brazilian Amazon. A total of 10,073 individuals of dung beetles were collected, belonging to 84 species in 22 genera. Forests areas (six secondary forest fragments) had 71 species and the pastures areas (neighboring areas where original forest was substitution by introduced pasture) had significantly lower richness (30 species), and community turnover between forests and pasture was very high. In forests the majority of species were generalist, while pastures showed higher abundance of coprophagous species, which shows a change in feeding guilds caused by the substitution of forest by pasture. Among 30 species collected in pastures, twelve are present in native open vegetation too (cerrado e chaco). That represents a recent regional colonization, where species of dung beetles, coming from open areas, are invading the Amazonian pastures.

Ecological theory of habitat heterogeneity and limited niche-similarity assumes that more heterogeneous environments provide a greater amount and diversity of resources than simple environments, resulting in a greater diversity of species. This study aimed to evaluate the effect of the habitat heterogeneity on the richness of dung beetles and to examine the spatial patterns of assemblage structure in relation to patterns of habitat heterogeneity. Dung beetles were collected using pitfall traps without bait in 30 points distributed in an area of cerrado sensu lato, in the region of Tangará da Serra, MT, Brazil, including areas of cerrado sensu stricto, campo sujo, cerradão and gallery forest. A total of 1,291 dung beetles were collected, distributed in 16 genera and 29 species. Overall habitat heterogeneity exerted a negative effect on patterns of dung beetles richness. Higher levels of species richness were observed in areas of cerrado campo sujo, while the areas of gallery forest were the most species poor. Regarding assembly structure, it was found that the dung beetles were separated into two major groups, one formed by the presence of specialized species in forest areas and other composed of species that occurred predominantly in cerrado. In conclusion, it was found that habitat complexity influenced the distribution of dung beetles, but the level of turnover in species composition along the heterogeneity gradient was relatively weak.