Characterization and Classification of Soils of the Terra da Esperança Settlement Project in Chapada do Apodi, Brazil

Abstract

Soil characterization and pedological classification are essential to define its main potentials and restrictions. The objective of this work was to classify the morphological, physical, chemical, and pedological attributes of soils of the Terra da Esperança Settlement Project (TESP) in Chapada do Apodi, Brazil, and find the most sensitive attributes for distinguishing them using multivariate analysis. The research was carried out in the TESP, in the municipality of Governor Dix-Sept Rosado, state of Rio Grande do Norte, Brazil. Ten sites were chosen to open representative soil profiles: Native Forest Area 1 (NFA1), 2 (NFA2), and 3 (NFA3), Collective Area with Native Forest (CNF), Agroecological Area (AEA), Cashew crop Area (CCA) Collective Area with Pasture 1 (CAP1), and 2 (CAP2), Permanent Preservation Area (PPA), and Cajaraneira (Spondia sp.) Orchard Area (COA). Disturbed and undisturbed soil samples were collected and subjected to physical and chemical analysis for soil classification. The soils classes found were: Cambissolo Haplico Carbonatico vertissolico (NFA1), Cambissolo Haplico Carbonatico tipico (CNF, and AEA), Cambissolo Haplico Ta Eutrofico tipico (CAP2, NFA2, and COA), Cambissolo Haplico Ta Eutrofico vertissolico (NFA3), Argissolo Vermelho Distrofico latossolico (CCA), Chernossolo Rendzico Ortico saprolitico (CAP1), and Neossolo Fluvico Ta Eutrofico tipico (PPA). The material of origin of the soils contributed to the presence of a calcic horizon in the profiles NFA1, CNF, AEA, CCA (Cambissolos), and CAP1 (Chernossolos). The textural class of the soils varied from sand to clay. The Argissolo (CCA) presented acid character, high aluminum saturation, low base saturation, dystrophic character, and low cation exchange capacity, forming horizons with chemical limitations, due to its latossolico character. The most sensitive attributes for distinguishing the soil classes were related to the source material, which directly influenced the soil physical (silt and clay) and chemical (acidity, salinity, nutrient availability, and clay activity) attributes.

Soil Attributes and Their Interrelationships with Resistance to Root Penetration and Water Infiltration in Areas with Different Land Uses in the Apodi Plateau, Semiarid Region of Brazil

“…Cambisols are considered young (little weathered) and show expressive silt fraction values, contributing to their compactness [53]. Freddi et al [54], in their study with a latosol (oxisol), found that soil density had a positive influence on the soil water content due to reduced macroporosity and the redistribution of pore sizes, corroborating the results achieved for the same soil class in this study (Figure 3a).…”

Characterization and Classification of Soils in Agroecosystems in a Moist Enclave in Northeastern Brazil

“…One of the environments is formed using the Acrisol soil class (P7) (Figure 3B), with aluminum and the clay fraction being the factors that most contributed to the differentiation of this class (Figure 3A), indicating a naturally more acidic soil, with a more advanced pedogenesis in relation to the other classes found. The authors of reference [37] used multivariate analysis to differentiate environments and also determined that aluminum was one of the most discriminant variables for the Acrisol class.…”