Characterizing phosphorus in environmental and agricultural samples by 31P nuclear magnetic resonance spectroscopy

Phosphorus nuclear magnetic resonance (P-31-NMR) spectroscopy has advanced our knowledge of organic phosphorus (P) in soils and environmental samples more than any other technique. This paper reviews the use of 31P-NMR spectroscopy for soil, water and other environmental samples. The requirements for a successful solid-state or solution 31P-NMR experiment are described, including experimental set-up, sample preparation, extractants, experimental conditions, and post-experimental processing. Next, the literature on solid-state and solution P-31-NMR spectroscopy in environmental samples is reviewed, including papers on: methods; P transformations; agricultural, forest and natural ecosystem soil studies; humic acid and particle size separations; manure, compost and sludge studies; and water research, including freshwater, estuary and marine studies. Future research needs are also discussed as well as suggestions to improve results, such as increased standardization among research groups. (c) 2004 Elsevier B.V. All rights reserved.