ResumoAs regiões de florestas tropicais estão em constantes transformações, em parte, resultantes do manejo por populações tradicionais aonde os sistemas de cultivo itinerante (agricultura migratória e de corte queima) desempenham um importante papel. No entanto, juntamente a estas discussões, são questionados os impactos e a sustentabilidade destes sistemas de cultivo e suas contribuições para o desmatamento. Diante disso, procuramos maiores informações sobre a prática da agricultura migratória por meio do estudo do uso e conversão de hábitat florestal em unidades produtivas agrícolas de duas comunidades tradicionais situadas em áreas de terra firme. Concluímos que indicativos da sustentabilidade desse sistema estão associados à prática integrada à floresta e ao período destinado ao pousio das áreas. AbstractTropical forest regions are in constant transformation, partly resulting from management by traditional populations where shifting cultivation systems (swiddenfallow and slash and burn agriculture) play an important role. However, along with these discussions, the impacts and sustainability of these farming systems and its contribution to deforestation are often called into question. Therefore, this research sought to generate information on the practice of shifting cultivation by studying the conversion of forest habitat to agricultural areas located in two traditional communities in upland areas of Central Amazonia. We conclude that the sustainability of this system is based on its character of being integrated into surrounding forests and the length of the fallow period maintained by farmers who engage in this practice.

Livestock activities in the Amanã Sustainable Development Reserve (RDSA) involve the production of cattle and buffalo in an extensive system, and are aimed at raising income and savings. As an expanding activity with high environmental impact potential, livestock is a focus of current discussion in this protected area. This study aimed to characterize livestock ranching activities and ranchers in the RDSA, highlighting key factors of production and management dynamics, as well as key impact indicators. For this purpose, we conducted semi-structured questionnaires with all 58 ranchers and geo-referenced their grazing areas. Areas of natural fields used as pasture were calculated through the use of satellite images. The main impact indicators identified for local livestock activity include: cultivated field growth, the increased use of várzea grasslands, and buffalo herd growth. To control the expansion of this activity, we suggest the development of regulations to guide herd management and the use of productive environments involved in ranching activities.