Distribuição da Cobertura Pedológica e Mapeamento de Solos Aplicado ao Manejo dos Solos em Silva Jardim - Rio de Janeiro

Abstract

Most of the soils in the world were developed under forest cover, but from the end of the 1700s (industrial revolution) the burning of coal caused a significant change in the way to use the soils, now excavated, mined and occupied. With the cities growing, it became necessary to intensify deforestation in order to provide new areas for these cities (BLUM, 2018). The general objective of the present work was to identify and map the types of soils, using toposequences, in a farm, located in the city of Silva Jardim, preparing soil mapping (1:10.000) and productive units mapping. For this, the Dom Bosco farm was chosen, where soil sequences from a transect were analyzed, with the opening of 9 soil trenches, respecting the positions of slope top, slope middle and slope base. Morphometric data and agricultural use were collected from the use of UAV and GNSS; which made possible to create a series of characterization maps. The orthophotomosaic generated has presented high resolution, it was possible to identify different agricultural cultures and uses. Studies on the different uses of the farm are complex, this entire area was initially deforested, with citrus culture being stablished, and later these areas gave up space to pasture, much of them degraded. The farm morphographic characterization reveals gently undulating hills, with an altitude between 3 meters and 65 meters, with 88% of the declivity varying from 3% to 45%. Plain areas can be observed, influenced by the local drainage scheme up to the Dam of Juturnaíba. It is interesting to note also that 32% of the areas have a slope of 20% to 45%, meaning that despite of being considered low altitude, a part of these hills have a higher slope, which requires an understanding and differentiated treatment in these areas that together to Argisoil-type soil become highly susceptible to erosion. As per the slopes curve, most of it (60%) presents a straight pattern. The farm's soils follow the clear sequence pattern of Ultisols and hydromorphic soils at the base of their slopes extending to the plains. Micromorphology points to A horizonts with contents mixed with subsuperficial materials, being called Ap horizont. Cutan presence was noted at several Bt horizonts. Soil mapping shows predominancy of RO mapa de solos mostra a predominância de Red-Yellow argisoil, yellow argisoil and gleisoil. It were defined and mapped 7 productive units that replace the production tract scheme, previously used at the farm. It is expected that the productive units mapping carried out may help agricultural production management, as well as soil handling, avowing its degradation. This way, this study area can be set as an example for other areas in the region.