CHARACTERIZATION OF CHEMICAL ATTRIBUTES OF A HORIZON ANTHROPIC IN NORTHEAST GLEYSOLS PARAENSE

Abstract

The aim of this study was to compare the chemical properties of soils of Indian black earth soils with no anthropogenic. The soil samples were taken in Tortoise archaeological site in Bragança / PA, which has a total area of 100m x 100m. The soil of this website belongs to the Order of Gleissolos. Samples were collected in three areas of the archaeological site (E1S1; E1S2 and adjacent area). For this study were collected at 5-10 cm depth. Ten simple samples were taken to compose a composite sample. The experimental design was completely randomized, with three areas of study and a soil type with 10 repetitions, each collection area within the site measures 10m. Total exchangeable bases, base saturation, exchangeable aluminum, aluminum saturation and effective CEC and CEC at pH 7: the variables were calculated. The average values of sum of bases, base saturation were higher in areas of Dark Earth. However, the average values of m% were lower in anthropogenic soils. While the average values of Al3+ were lower in point E1S1 the archaeological site. The effective CEC was higher in areas E1S1 and E2S1 (29.21 and 20.93 cmolc/dm3 respectively) and lowest in the area (5.55 cmolc/dm3). While the average values of CEC at pH 7 was higher in areas E1S1 and E2S1 (41,88 and 32,39 cmolc/dm3 respectively) and Adjacent the lower (15 cmolc/dm3) area. The black earth indiums present are more fertile than non-anthropogenic soils.   KEYWORDS: archaeological site, chemical characteristics, fertility.