The seed Brazil nuts has high food value and is considered one of the main extractive products of the export zone of the northern region of Brazil. The study of the ecological and biological aspects of Brazil nuts (Bertholletia excelsa) has been the objective of many studies, but the amount of research that approach the social and environmental variables related to the species is incipient. In this context, the present thesis sought to evaluate the edaphic attributes that most influence in plant development and litter production in the native castanhal area of the Tapajós National Forest (Tapajós FLONA), in addition to studying the socioeconomic factors and management practices, collection and the production of extractivists of Brazil nuts that reside in this area. The presentation of the obtained results was exposed in three chapters: the first chapter includes a geostatistical analysis of the physical-chemical factors of the soil; the second presents an estimate of the litter production in relation to the monthly average of the maximum temperature and the monthly totals of precipitation and insolation; and the third shows an analysis of the economic, social and management aspects of the Brazil nuts collectors that work in the Tapajós FLONA. The field samples were performed in a permanent 300 m x 300 m portion of the MapCast project, installed at km 84 of the Tapajós FLONA. The soil sample collections for the physico-chemical analyzes followed the recommendations described in the "Manual of laboratory: soil, water, plant nutrition, animal nutrition and food" of Embrapa, as well as the procedures for analytical determinations. For the litter collection, 12 containers were used in circular format and the deposited material was collected every 30 days and separated into classes (leaves, flowers and fruits, woody, miscellaneous). Socioeconomic, production and the form of extraction data of Brazil nuts were obtained through a structured interview conducted with 24 extractivists from the region. By Simple Kriging it was possible to estimate the concentration of nutrients studied for the entire area of the sample grid. The densification of Brazil nut trees was identified in areas with higher silt and clay values and lower values for macroporosity, pH, phosphorus, zinc and copper. Leaf production ranged from 169.9 to 965.6 kg ha-1 month-1, wood between 26.7 and 501.3 kg ha-1 month-1 and flowers and fruits between 0.6 and 19.6 kg ha-1 month-1. The wood and flowers and fruit classes presented no significant variation (p> 0.05) and no significant correlation with any meteorological variable. The three environmental variables analyzed explain 40.7% of the temporal variability of litter production. In all, 39 Brazil nuts extractivists were recorded. Most of these have a low level of education and are covered by the “Bolsa Família Program”. The production varied significantly between the 2013/2014, 2014/2015 and 2015/2016 harvests, and extraction practices are traditional. The Geostatistical Analysis allowed the knowledge of the current spatial distribution of the physical and chemical attributes of the soil in the studied area, which will serve as a basis of comparison for future evaluations in the same place and also to help understand environmental aspects in areas with agglomerations of Brazil nuts. The environmental variables temperature and insolation influence leaf production and total litter production in native castanhal area. The management practices of the castanhal and the collection and processing of the seeds applied by the extractivists of the studied communities do not present any innovation in relation to the traditional and rudimentary practices already informed in the literature. The variation between the harvests was influenced by the reduction of rains (caused by an event of El Niño installed in 2015) and by the frequent burned, according to the perception of the interviewees.
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