COMMENTS ON THE CATCHMENT EXPERIMENT TO DETERMINE VEGETAL EFFECTS ON WATER YIELD1

Abstract

ABSTRACT So far most applicable knowledge about forests and water yield has come from catchment experiments. Perhaps even more practical information might have been secured during the past twenty years if more and better designed catchment experiments had been undertaken. At the very least, the old question of the main effects of vegetation on total basin water yield should now be settled, and we should be in a position to write management prescriptions containing reliable estimates of differing water yields under crop, pasture, brush and forest lands. As things are, managers and policy makers are being forced to decide what combinations of vegetal cover and land use best favor water yield before the scientific community has fully agreed on some of the salient aspects of the problem. This has led to considerable confusion in the minds of land managers in many regions of the world and may continue to do so for some time. The catchment experiment remains the surest way to furnish each region with practical knowledge of local vegetation‐water‐yield relations.