Soil health and sustainability of quilombola family agroecosystems in the Amazon

Abstract

This thesis is part of the studies on soil health and sustainability of agroecosystems in Eastern Amazonia. In the Amazon region, peasant communities face a crisis in the traditional systems of farm management and fertility of the natural environment which is based on the slash-and-burn technique, imposing questions on the sustainability of agroecosystems. To address these challenges, changes in agricultural practices in local production systems are observed, especially with the adoption of agroforestry systems. Given this scenario, the research question of this thesis is: how do agricultural land management practices evolve, and what are the impacts on soil health and the sustainability of agroecosystems in quilombola communities in Eastern Amazonia? The central hypothesis is that changes in land use and socio-productive strategies of quilombola farmers improve soil health. Thus, the central objective of this thesis is to analyze soil management practices and their impacts on soil health and the sustainability of quilombola agroecosystems in Eastern Amazonia. The specific objectives are: i) to evaluate current practices and transformations in agricultural land management; ii) to identify and evaluate local perceptions of the role of soil in the sustainability of agroecosystems; iii) to promote the integration of analytical methods and participatory field evaluations in constructing knowledge about soil health. The empirical reference of the research is the Quilombola Community Oxalá de Jacunday, Moju, Pará. The theoretical-analytical approach of agroecology and ethnopedology guided the research and the discussion of the results obtained. These results are presented in three chapters: Chapter I evaluates the transformations in land use forms and the socio-productive strategies adopted by farming families; Chapter II assesses soil health based on four plots representing the land use forms by quilombola farmers, with central indicators being soil macrofauna and soil structure assessment; Chapter III analyzes the co-construction of knowledge about soil health through participatory methodologies and the dialogue of knowledge. The participatory research with farmers showed that agricultural practices have undergone various changes due to both internal factors of agroecosystems and external factors such as pressure from agro-industrial companies, road openings, and traditional territory recognition policies. The slash-and-burn system is in decline, and families have specialized in cassava production for flour making. Thus, agricultural practices have evolved towards more diversified systems that can protect the soil, such as agroforestry systems. Therefore, the results confirm the hypothesis that quilombola families have managed to maintain soil health with their practices.