Studies through descriptions and samples of soils made in field profiles are necessary to understand the factors that better define the variations of physical properties of the soil, both under natural conditions and under crops in general. The present work aims to analyze some parameters that influence the physical conditions of soils, such as grain size, density and porosity of soils. To this end, three soil profiles were selected from the Algodoal/Maiandeua-PA island, classified in Amaral (1998) as: Yellow Argissolo (profile P2), Sodic Fluvic Neosolo (profile P3) and the Fluvic Neosolo (profile P5). The Algodoal/Maiandeua APA, located in the municipality of Maracanã, is characterized by an average annual rainfall of 2,800 mm, distributed in two distinct periods: a rainy period, which extends from December to May, and a period of very low rainfall, which reaches the other months of the year. The dominant natural vegetation is composed of mangroves and restinga forests, however, anthropic intervention has greatly modified the natural landscape, which is composed of two major relief systems: Coastal Plateau, which corresponds to the higher lands, flat terrain and better drained; and Coastal Plain, which corresponds to the lower lands, with gently undulating terrain, where drainage is poor. The granulometric data show that the texture varied from medium to sandy, with the exception of profile P5 where the sandy texture predominated, and that the soil material is composed predominantly of sand, being poor in clay, with some variation in silt content along the profiles, with an accentuated content in the superficial horizon Ado profile P3 probably due to the deposit of materials brought by the tides. The clay content was low in the superficial horizons, increasing with depth, with a relative increase in the Bt horizons of the P2 profile, although the texture varied from medium to sandy. In this work only the data from the granulo-metric analysis are being analyzed, since the density is still under laboratory analysis.
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