Soluble Salts in Dune Sands from Blakeney Point in Norfolk

Abstract

Analyses of pH, specific conductivity, optical density, Na, K, Ca, Mg, NH4, HCO3, Cl, SO4, PO4, NO3 and SiO2 are presented for filtrates from 51 equilibrium mixtures of H2O and dune sands. The mobile dune phases are richer in soluble Ca, NO3 and SiO2; while the stable phases are richer in soluble organic carbon, NH4 and PO4, and as regards the older dunes in soluble K and SO4 as well. Filtrates from Carex arenaria communities are more acid and poorer in lime than those from Ammophlla-Festuca communities. Ion-exchange processes similar to those in arid alkali soils appear to be responsible for Ca/HCO3 ratios of less than 1, and Na/Cl and Mg/Cl ratios much greater than in sea water.