CHANGES IN SULFATE RETENTION, SOIL CHEMISTRY AND DRAINAGE WATER-QUALITY ALONG AN UPLAND SOIL TRANSECT

Soils sampled along an altitudinal transect in an upland area of North East Scotland have been used to investigate downslope changes in the capacity of soils to retain sulphate. Simulated laboratory experiments involving the leaching of reconstituted cores with 'rainfall' contain ing low (1.85 mg litre-1) and high (51.90 mg litre-1) concentrations o f sulphate indicate that soils developed on upper slopes have a limite d capacity to adsorb sulphate, whereas soils on lower slopes have a mu ch greater sulphate adsorption capacity. Soil drainage water, produced from 'sensitive' upper slope soils may therefore be significantly mod ified by physico-chemical reactions in lower slopes before reaching wa tercourses.