Capillary Movement of Nitrate towards Tropical Soil Surfaces

Abstract

As in many other parts of the tropics, accumulation of nitrate in the top inch of soil during the dry season has been observed at Katherine, Northern Territory, Australia, on a red sandy clay loam. The accumulation could be caused by a complex of processes of a physico-chemical, photo-chemical, biological or physical nature. Experiments at Katherine have shown that capillary movement has been obscured, rather than overlooked, as the main cause.