Affiliation: | 1. STANLEY W. TRIMBLE is Associate Professor of Geography at the University of California, Los Angeles 90024-1524. His principal interests are in environmental history, human-induced hydrologic and landform changes.;2. RONALD U. COOKE is Professor and Head, Department of Geography, University College, London, WC1E 0AP, United Kingdom. His principal interests are in dryland and applied geomorphology. |