Formigas em processos ecológicos às margens do rio Pandeiros: plantadoras de floresta ou cortadeiras de roça?

Abstract

Conservation units for sustainable use are excellent alternative for preserving nature and biocultural richness of communities and territories. In the Pandeiros River Environmental Protection Area (EPA), north of Minas Gerais, a rich Cerrado-Caatinga transition biodiversity and peasant and traditional communities coexist. In addition, pioneering studies in South America evaluate the feasibility of removing the small hydroelectric plant at Pandeiros, na important affluent of São Francisco River. In this context, our first chapter studied the annual recolonization by ants regarding specific diversity and removal of diaspores in riparian environments of Pandeiros. We used epigeic pitfalls and active collection with artificial diaspores in eight linear transects of up to 80 m, perpendicular to water. We found 29 genera and 113 ant morphospecies, predominant generalists and opportunists; rate of removal of diaspores and potential removers ants were low. There was not variation between dry and rainy season for species richness and composition, removal of diaspores and grass cover; other environmental vegetation variable, plant density, increased in the rainy season. We observed variation on richness and composition in relation to the distance from water, indicating water-land ecotone acting as possible environmental filter for recolonization by ants. Thus, we suggest measures to revegetate the area after eventual dam removal, complementing this ecological mirmecofauna’s process, and new studies about ants recolonization and their ecological processes in riparian environments. In the second chapter, we characterize the local ecological knowledge (LEK) about ants, their activities and importance observed and attributed by 24 inhabitants of Pandeiros. We used ethnoecological indices of participant’s consensus and we highlighted the group of leaf-cutters, especially the “formiga-de-mandioca” (manioc-ant) and rapa-rapa, followed by the “formiga-malagueta” (fire-ant), all with synonyms. In addition to this classic approach, to analyze an interview with a key participant, we approach the dialogism of Bakhtinian's philosophy of language to the signification nuclei based on historical-dialectical materialism. We compare our results with scientific knowledge regarding ants, the history and socio-environmental context both of EPA and the Minas Gerais hinterland ("sertão"). Converging and deepening all the results, we saw that the leaf cutters ants are the dynamic and organizing center of the myrmecological LEK in Pandeiros, around it orbiting other ethnospecies in different degrees of concentration and dispersion. We believe that it is due to the great interaction between leaf cutters ants and people in agricultural work and the negative impact on staple foods of region's characteristic subsistence, especially manioc. Finally, relating the chapters, we identified a distance due to apparent ignorance: removal of diaspores by ants is not easily observed and has not integrated the myelecological LEK, although it is a fundamental ecological process for plant dispersion; in fact, the general understanding of ants is negatively associated with agricultural pests. Thus, we emphasize the need to build participatory forms of dialogue and production between scientific and popular knowledge, enable joint activities to value and apprehend new dimensions of the community's LEK and share what we have learned with people and ants on the banks of the Pandeiros River.