Abstract
The soil and vegetation characteristics of the southern Amazonas region include highly weathered soils, high aluminum content and some hydromorphic conditions, its vegetation is composed from grasslands to small isolated trees and forest galleries along the rivers streams. In this way, this work aims to characterize and classify the soil in areas of clean field, dirty field, and forest in Humaitá region AM. Soil trenches were opened in the clean field, dirty field, and forest environments, soil profiles were morphologically characterized, and samples were collected from their horizons. Physical analysis of texture, dispersed clay in water, flocculation, bulk density, particle density and porosity were performed. The chemical analyzes included pH and KCl in water; Ca, Mg, K, Al, and; available P; H+Al and organic C; SiO2, Al2O3 and Fe2O3 sulfuric attack. The soils were classified according to criteria established by the Brazilian System of Soil Classification and Soil Taxonomy. The forest, dirty field (high) and clean field (low) showed different soil types, Typic Dystrudept for the first two environments and Typic Fluvaquents for last. Multivariate techniques expressed the similarity relations presenting between the different environments studied, characterizing, which are of great importance in the relation landscape-soil studies.
Highlights
The landscape is the combination of the earth surface features and the subsurface components (PENNOCK; VELDKAMP, 2006), while soil is a natural threedimensional and dynamic body that is inserted in the landscape (MINASNY; MCBRATNEY, 2006)
This landscape type includes several open country formations, alternating small isolated trees and forest galleries along the streams known as “igarapés” (BRAUN; RAMOS, 1959). These fields form some mosaics with the surrounding forests, the contact between these vegetations occurs in some places, abruptly, but in others the vegetation changes between the forest and the field is gradual (FREITAS et al, 2002)
Regarding the soil taxonomy it was observed the formation of two classes according to the SiBCS: the first in the Entisols order (P1), the second and the third in the Inceptisols order (P2 and P3)
Summary
The landscape is the combination of the earth surface features and the subsurface components (source material) (PENNOCK; VELDKAMP, 2006), while soil is a natural threedimensional and dynamic body that is inserted in the landscape (MINASNY; MCBRATNEY, 2006) In this way, the relation "soil-landscape" can be understood as the soil attributes spatial pattern distribution and its dependence relations with the landform arrangement (CAMPOS et al, 2007). The Amazonas region presents a great soil diversity and landscapes, which justifies studies of this nature, among these landscapes, the Humaitá city presents transition vegetation of the Field/Forest type, which includes the so-called “Humaitá Natural Fields”, that comprise the areas of the "PuciariHumaitá fields” This landscape type includes several open country formations, alternating small isolated trees and forest galleries along the streams known as “igarapés” (BRAUN; RAMOS, 1959). These fields form some mosaics with the surrounding forests, the contact between these vegetations occurs in some places, abruptly, but in others the vegetation changes between the forest and the field is gradual (FREITAS et al, 2002). Braun & Ramos (1959) add that vegetative associations occur, forming the: "clean field" areas which are not very extensive and with grasses predominance; the "dirty field" areas are dominated and covered by grasses associated with shrubs and trees and in the areas near the fields edges occur woods, with trees spacing between 1 and 3 m, reaching 3 to 5 m height
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
