USE OF P-31-NMR TO STUDY THE FORMS OF PHOSPHORUS IN PEAT SOILS

P-31-NMR has been used to characterise the major forms of organic and inorganic phosphorus in soil derived alkali extracts and humic acids. Blanket peat, which had been under different fertilisation treatments for 10 years was compared with an agricultural mineral soil. In the mi neral soil the phosphorus was shown to be in the form of inorganic ort hophosphate and phosphate monoesters whereas the peat soil also contai ned phosphate diesters and other inorganic forms of phosphorus. Change s in various phosphorus pools in the peat soils were shown to correlat e with differences in fertilisation regime and land management practic e. Fertilisation with superphosphate increased phosphate monoester con tent in the peat, although vegetation type appeared to have greater im pact on the phosphate monoester concentration. The degree of microbial activity, as indicated by the presence of polyphosphates and absence of phosphonates, correlated positively with vegetational improvement a nd fertilisation of the peat soils.