Miriam Plaza Pinto

Conservation biogeography of anurans in Brazilian Cerrado

The increasing rates of declines in anuran populations worldwide are creating demands for urgent strategies to maximize conservation efforts. This may be critical in regions for which few detailed data on diversity, abundance and distribution are available, such as in the Cerrado of Central Brazil. In this paper, we used a macroecological approach based on the extent of occurrence of 131 species of Anura (Amphibia) in the Cerrado region to design a regional network of potential areas that preserves all anuran species. The final network, obtained using a simulation annealing algorithm based on complementarity, has a total of 17 cells, widely distributed throughout the biome. Minimum costs solutions were obtained in respect to total human population size, soybean production and bovine density, because these are the factors associated with human occupation that historically are more likely to cause broad scale habitat losses. The macro-scale approach used here can provide overall guidelines for conservation and define the focus for more local and effective conservation efforts.

Conservation planning: a macroecological approach using the endemic terrestrial vertebrates of the Brazilian Cerrado

Increasing rates of habitat loss and human occupation are creating demands for optimum strategies that maximize conservation efforts, despite the lack of detailed data required for implementation. Broad scale biogeographical data may furnish initial guidelines for conservation planning in a hierarchical framework for establishing conservation priorities and helping guide future research programmes. This approach may be critical in regions for which few detailed data on diversity, abundance and distribution are available, such as in the Cerrado biome of central Brazil. We used a macroecological approach, based on the extent of occurrence of 127 species of terrestrial vertebrates endemic to the Cerrado, to design a regional network of potential areas that represent all species at least once. The final network has a total of 24 regions widely distributed throughout the biome. We also evaluated these regions in terms of their human occupation by adding a cost for each cell based on 23 variables expressing variation in agricultural, demographic and cattle-ranching patterns on the Cerrado. Our analyses showed that conservation efforts should be concentrated in the south and south-east of the biome. This macro- ecological approach can provide broad guidelines for conservation and define the focus for more local and realistic conservation efforts.

Patterns of the aquatic macrophyte cover in Cachoeira Dourada Reservoir (GO-MG)

The relationship between the aquatic macrophyte cover in upper segments of tributaries and this cover in these tributaries but near the reservoirs main body was tested. Sixteen taxa belonging to 12 families of aquatic macrophytes were recorded in Cachoeira Dourada Reservoir. The most frequent species were Eichhornia azurea (frequency of occurrence=92%; n=37 sites) and E. crassipes (44%). Upper segments of the tributaries were the main areas colonized by these aquatic macrophytes. The positive relationship between the aquatic macrophyte cover between the upper and lower segments of tributaries indicates the importance of dispersion in the colonization of the arms and the reservoirs main body.

Selecting priority areas to conserve Psittacines in the Brazilian cerrado: minimizing human–conservation conflicts

The rapid destruction of habitat in biodiversity hotspots calls for the urgent formulation of conservation strategies. In this study, macro-scale biogeographical data for 33 species of Psittacines were used to select networks of priority areas, using an algorithm based on the complementarity concept. Human population size was also incorporated as a cost in the selection process, and the two networks of priority areas (with and without cost) were compared. In the comparison the number of cells selected to represent all species did not differ, but a rearrangement occurred between them. Two of the four cells were located in the same place, and the others changed location but stayed aggregated within the same regions. The study shows that it is possible to minimize human population size and represent all species in a network of priority areas.

Associação de Constrictotermes cyphergaster Silvestri (Isoptera: Termitidae) com espécies arbóreas do Cerrado brasileiro

Termites usually build nests differently shaped and characterized according to each species, to protect and keep society cohesion. Some species build nests in the ground, some prefer tree thunks or branches as support, whereas other dig galleries in the wood. The purpose of this study is to analyze the relationship between the occurrence of arboreal termites Constrictotermes cyphergaster Silvestri and tree species that support the nest of this species, in a Cerrado sensu strictu of the Serra de Caldas Novas, GO. Data suggest a association relationship between C. Cyphergaster and the tree species Qualea grandiflora Mart., Annona crassiflora Mart., Caryocar brasiliense Camb. and Plathymenia reticulata Benth., shown by high Qui-squared values (chi2 = 214.986, gl. = 20, P < 0.001). This relationship may be found among other termites and tree species, including Cerrado biome, and may be due to several factors, such as natural competitors and predators, toxin production by other tree species or benefits between associated species (facultative mutualism or facilitation).

Escolha de áreas prioritárias de conservação de anfíbios anuros do Cerrado através de um modelo de populações centrais-periféricas

Uma das maiores ameacas a diversidade biologica e a perda de habitat, de modo que uma das alternativas para protecao da biodiversidade e a selecao de reservas pela utilizacao de procedimentos de otimizacao para estabelecer areas prioritarias para conservacao. Neste estudo, um algoritmo simulated annealing foi usado para verificar como a periferia das distribuicoes das especies influencia na selecao de areas no Cerrado para conservacao de 131 especies de anfibios anuros. Dois conjuntos de dados foram analisados, um contendo a distribuicao original das especies e outro excluindo a periferia das distribuicoes. As redes otimas encontradas a partir das distribuicoes originais contiveram 17 quadriculas enquanto aquelas encontradas a partir das distribuicoes restritas foram maiores, com 22 celulas. As celulas com alto grau de insubstituibilidade foram mantidas em todas as redes e novas regioes de celulas substituiveis, localizadas na margem do bioma, surgiram quando apenas as distribuicoes reduzidas foram usadas.