Geochemical characterization of phosphate mineralization in quartzite outcrops of the Borborema Province, NE Brazil: potential for utilization with ecological impact mitigation

Abstract

Phosphate is a strategic mineral resource that is essential for agricultural production and global food security. In Brazil, most phosphate production originates from carbonatite complexes, while data on deposits in semiarid regions—such as the Borborema Province—remain limited. This study assesses the potential for sustainable exploitation of phosphate mineralization in quartzite outcrops located in the municipality of Palhano, Ceará. The methodology included the collection of ten representative rock samples for geochemical analysis and the establishment of five 10 × 10 m plots for a phytosociological inventory of the Caatinga vegetation. Major oxides were quantified using X-ray fluorescence (XRF), and trace elements were determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The results revealed heterogeneous phosphate mineralization, with phosphorus pentoxide (P₂O₅) concentrations ranging from 0.68 % to over 40 %, including high-grade phosphorite samples (>30 % P₂O₅). The vegetation survey indicated low species richness and a dominance of pioneer species, such as Croton blanchetianus, which are typically associated with disturbed or regenerating environments. Spatial distribution patterns, assessed using the Payandeh Index, confirmed aggregation behavior consistent with ecological degradation. These findings suggest that phosphate extraction in the study area may be viable under sustainable management strategies. The integration of lithogeochemical and ecological data supports informed decision-making aimed at reconciling mineral resource development with biodiversity conservation in environmentally sensitive semiarid landscapes.