Ferralsols and plinthosols derived from the degradation of crusts of the Serra dos Martins formation in the brazilian semiarid region

Abstract

In a landscape characterized by etchplanation under a semi-arid climate, with summits formed by mesetas and ferruginous crusts, found in the states of Paraíba and Rio Grande do Norte, Brazil, there is pedogenesis of Ferralsols (meseta cores) and Plinthosols (meseta edges). This research aims to characterize soils derived from the alteration of the ferruginous crust of the Serra dos Martins Formation. The studied soils were cataloged in the municipalities of Areia, Bananeiras, and Cuité, involving the examination of six soil profiles: Umbric Xanthic Ferralsol (P1), Petric Xanthic Ferralsol (P2), Petric Xanthic Ferralsol (P3), Haplic Petric Plinthosols (P4), Haplic Petric Plinthosols (P5), and Haplic Petric Plinthosols (P6). These were described and classified according to the WRB/FAO, with a focus on macromorphology. The Ferralsols vary from deep to moderately deep, are chemically poor, kaolinitic, and exhibit intense biological activity. The Plinthosols (P1, P2, and P3) feature A horizons with a granular structure and concretionary FA horizons (petric). These characteristics reflect the complexity and diversity of the soils of the Serra dos Martins Formation.