Exchange, experimentation and preferences: a study on the dynamics of manioc diversity in the Middle Solim es, Amazonas

The paper presents a study on the manioc diversity in the Middle Solim es region, focusing largely on communities located in the Sustainable Development Reserves of Mamirauá and Aman , state of Amazonas, Brazil. The study combines quantitative and ethnographic data. The analysis of survey data collected in 13 communities in the 'várzea' and in the 'terra firme' revealed the following pattern of manioc diversity: a total richness of 54 varieties, demonstrating a broad distribution of a small number of varieties and a local occurrence of the majority; an average richness of ten varieties per community; and an average of three varieties maintained per household. A temporal analysis of survey data collected at the household level illustrates the dynamic nature of this regional diversity. Over the course of five years, almost all the 55 accompanied families altered the composition of manioc varieties in their collections; however, the size of these collections showed little variation. To discuss the dynamics of diversity, we conducted qualitative research in three communities. This analysis sought to understand the social and environmental conditions with which farmers contend, patterns of manioc management, and the logic behind farmers' preferences for certain manioc varieties. The research demonstrates that maniva diversity is a result of active experimentation, and that collections of manivas maintained by farmers are dynamic and ever-changing. This dynamism is defined by a series of factors that include economic practices, environmental conditions, and the historical relationship of the regional population with manioc.