Sistemas agrícolas e plantas medicinais em terras pretas de índio da Amazônia Central

Abstract

The objective of this thesis was to obtain information about the diversity of species and management practices in rural properties with Amazonian Dark Earth (ADE). In a first chapter, we described the agricultural systems of 12 farms located in Santana Community, Costa do Laranjal, Manacapuru, Amazonas state, Brazil. We pointed out that farmers only cultivate in ADE, and that homegarden is the principal agricultural system and the most important source of income to the households in the study area. Although there is no intencionality in the recreation of the ADE, some management practices applied by the studied farmers are probably maintaining the fertility of this kind of soil in their farms. In a second chapter, we pointed out factors that influence the occurrence of medicinal plants on ADE in the 12 farms studied comparing them with one farm without ADE, in the same community. The homegardens are the only source of medicinal plants in the Santana Community. Eighty-seven medicinal species were found, which means 60% of the useful species found in the studied homegardens. The regional origin of the farmers of Santana Community and their social relationship with neighbors and friends determine, in the most part, the cultivated and spontaneous tolerated medicinal species in the study area. However, some observations indicated that the presence of ADE could be influencing the community of medicinal plants in the studied area. Among these observations, we can outstanding a low proportion of medicinal weed species (21%) and a high proportion of exotic species (77%), which differ from results found in other studies carried out in rural communities without ADE. The absence of species from the Zingiberaceae family in the farm without ADE point to the existence of species associated with this kind of soil. The results reported here confirm the ability of the ADE to the cultivation of exotic species and demonstrate that ethnobotanical studies carried out in rural communities must take the soil into account.