The error in stream sediment phosphorus fractionation and sorption properties effected by drying pretreatments

We found that drying sediment significantly influenced EPC0 and P fractions (especially the NH4Cl-P fraction). Air-drying was particularly error-prone and should be avoided. The use of freeze-drying to preserve samples for later analyses and improve ease of handling may be used with appropriate consideration of the research objectives and the error introduced by freeze-drying. However, we recommend using fresh sediments for analyses whenever possible, as they best represent natural conditions.