The sulphur content and pH of rainfall and of throughfalls under pine and birch.
Sulphur in rainfall and throughfall was measured at weekly intervals over 2 yr at a heathland site and under Pinus sylvestris and Betula pendula canopies in Berkshire, UK. Concentrations of S in throughfall were generally greater than in rainfall and were greater for P. sylvestris than for B. pendula, but actual amounts of S reaching the forest floor were similar to those in heathland. Increased S concentrations were therefore attributed to interception evaporation losses. The pH of throughfall was lower than that of rainfall, but there was no evidence that this was due to washing off of adsorbed sulphate.