Influence of Sample Pretreatment on P Speciation in Sediments Evaluated with Sequential Fractionation and P <i>K</i>-edge XANES Spectroscopy

Sequential phosphorus (P) fractionation procedures are one of the most widely used wet chemical methods for characterizing P pools in soils and sediments, but have also been criticized repeatedly their lack accuracy to measure chemically specified phosphate fractions. In recent investigation, sediments from two different sample locations with same pretreatments were analyzed sequential fractionation. To verify traditional assignments results, K-edge X-ray absorption near edge structure (XANES) spectroscopy was applied on especially residues after extraction steps. Results both indicated that influence pretreatment distribution much lower compared effects origins. Kettle hole dominated by moderately labile iron (Fe) aluminum (Al) associated species, whereas Bodden contained more stable calcium (Ca)–P species. Sample can be similar soil without causing fundamental changes speciation. The XANES confirmed assumptions