Concentrations of P, K, Al, Fe, Mn, Cu, Zn, and As in marl soils from south Florida

Enrichment of nutrients (P) and trace elements (As, Fe, Cu, Mn, and Zn) in soils has contributed to the degradation of the Everglades ecosystem. Bette r understanding of elemental concentrations in soils is important for resto ration and conservation of this fragile ecosystem. In this study, concentra tions of P, K,AI, Fe, Cu, Mn, Zn, and As in 13 archived disturbed and undis turbed marl soils and five recently-collected undisturbed marl soil profile s from south Florida were determined using EPA Method 3051a (microwave, HNO 3/HCl = 3:1, v/v). Geometric mean (GM) concentrations of P, K,AI, Fe, Mn, C u, Zn, and As in surface marl soils were 256, 212, 5100, 2800, 60.3, 3.81, 13.9, and 4.31 mg kg(-1), respectively, which were 2.6 to 15.8 times greate r than those of Florida soils. No significant differences in elemental conc entrations were found between the archived and the newly-collected soils, o r between disturbed and undisturbed soils. Based on factorial analysis and spatial distribution similarities, these elements were divided into three g roups: Group 1 (As, Fe, Cu, Al, and P), Group 2 (K and Zn), and Group 3 (Mn ). Elevated elemental concentrations in marl soils may not all originate fr om anthropogenic sources and may attribute to elemental accumulation during formation of calcite.