Murphy,P.N.C., Bell,A. and Turner,B.L.(2009): Phosphorus speciation in temperate basaltic grassland soils by solution 31P NMR spectroscopy. European Journal of Soil Science, 60, 638-651.

『溶液31P核磁気共鳴分光法による温暖な玄武岩質草地土壌におけるリン化学種の同定』


Summary
 Phosphorus (P) speciation in 21 basaltic and four non-basaltic Irish grassland soils was determined by NaOH-EDTA extraction and 31P NMR spectroscopy. Organic P in basaltic soils ranged between 30 and 697 mg P kg-1 and consisted of phosphate monoesters (84-100%), DNA (0-16%) and phosphonates (0-5%). Inorganic P was mainly phosphate (83-100%) with small concentrations of pyrophosphate (0-17%). Phosphate monoesters were more important as a proportion of extracted P in basaltic soils, probably because of their greater oxalate-extractable Fe and Al contents. Phosphate monoesters appeared to be strongly associated with non-crystalline Al and increased with total soil P concentration, indicating that they do accumulate in grassland soils. In non-basaltic soils myo-inositol hexakisphosphate constituted between 20 and 52% of organic P, while scyllo-inositol hexakisphosphate constituted between 12 and 17%. These compounds were not quantified separately in basaltic soils because of poor NMR resolution in the phosphate monoester region, but appeared to represent a considerable proportion of the organic P in most samples. DNA concentrations were greater in basaltic soils compared with non-basaltic soils and were associated with acidic pH and large total C contents. The inability of the Olsen P test to assess effectively the P status of basaltic soils may result from strong phosphate sorption to Fe and Al oxides, inducing plant utilization of soil organic P. Phosphorus nutrient management should account for this to avoid over-application of P and associated financial and environmental costs.』

Introduction
Materials and methods
 Soil sampling and analysis
 Solution 31P NMR spectroscopy
Results
 Soil properties
 Soil phosphorus
 Correlations between soil properties and soil phosphorus
Discussion
 Phosphorus speciation and soil properties
 Implications for P plant availability
Conclusions
Acknowledgements
References


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