Seasonal availability of chemical nutrients on Signy Island

This paper presents some preliminary results of an investigation into the seasonal variation of extractable n utrients in the soils of Signy Island. In an examination of British soils Allen & Grimshaw (1962) found that extractable phosphorus and ammonium -nitrogen concentrations increased as a result of prolonged freezing. In view of the importance of such phenomena to the soils of subpolar regions experiments were carried out on Signy Island over a complete season. Signy Island is particularly suitable for such a study because of the prolonged freeze during the winter months, and the oscillation of the soil temperatures around 0 °C during the rest of the year.