『（Abstract)
　We assessed the influence of sample pretreatment on the amounts and forms of P extracted in NaOH-EDTA (ethylenediamine tetraacetic acid) from a series of contrasting wetland soils from the Florida Everglades. Samples of unconsolidated benthic floc and underlying soil (0-10 cm) were extracted either fresh (overnight refrigeration only), air dried (10 d at 〜30℃), or frozen at -80℃ and lyophilized (〜48 h), before extraction and solution ³¹P nuclear magnetic resonance (NMR) spectroscopy. Significant differences in total P extraction following pretreatment were detected for one out of four benthic floc samples and three out of four soil samples, although the changes were inconsistent: in two cases the total P extraction increased, while in two others it decreased. Assessment of the P composition by solution ³¹P NMR spectroscopy revealed differences among treatments, although these were mostly within the range of error associated with replicate analyses; however, DNA was not detected in a fresh sample of calcareous benthic floc, despite representing an important component of the organic P extracted from dried samples. The apparent sample-specific nature of the changes confirms the importance of carefully assessing pretreatment effects in studies of soil organic P in wetlands.』

Abbreviations
(Introduction)
Materials and methods
　Sampling and pretreatment
　Phosphorus extraction and analysis
　Solution phosphorus-31 nuclear magnetic resonance spectroscopy
　Chemical analysis
　Statistics and data presentation
Result
　Soil properties
　Total phosphorus recovery by NaOH-EDTA extraction
　Replicate nuclear magnetic resonance analysis
　Phosphorus composition by solution phosphorus-31 nuclear magnetic resonance spectroscopy
Discussion
Conclusions
Acknowledgments
References