Water Properties of Caliche

Abstract

Water absorption and retention by hard caliche nodules (rocks) collected from soils in southern New Mexico were determined. The rate of water uptake by the caliche rocks was rapid and water content at saturation was 13.0% by weight (24.7% by volume). At a matrix potential of -0.7 MPa, the rocks retained 10.6% water by weight, an 18% loss from saturation. Water loss from saturated rocks to a dry atmosphere was slow, but most of the absorbed water was released. The rocks contained only 0.6% water by weight (1.1% by volume) after 34 days in a desiccator. Both laboratory and field trials indicated that, although indurated caliche layers will absorb large amounts of water, the water does not pass through the layers to the soil below.