A Simple Method for Measuring Soil Redistribution on Hillslopes

Abstract

Human activities and associated land-use changes often result inaccelerated soil movement on hillslopes. The impacts of such soilmovement can be dramatic both on- and off-site. Appropriate strategiesfor mitigation or control erosion and mass movements are especiallycritical for application in tropical countries, where steep slopes areincreasingly converted from forest to agricultural use and are subjectto intense precipitation. The immediacy of the need for erosion controland limited access to research institutions often results in a gapbetween extension and testing of erosion control strategies for thesesettings. To address this need, a transect datum technique wasdeveloped to assess rates of soil redistribution and loss on steep,deforested slopes with thin, calcareous soil in the Philippines. Themethod is simple, inexpensive and robust and does not require disturbingthe soil surface, as do erosion pins. Application of the technique forthree years to several land uses, including contour hedgerows, acontour-plowed field without hedgerows, slash/burn no-till, and pasturedemonstrated the technique sensitive enough to measure fluctuations insoil height associated with changing bulk density, soil redistributionand loss and slumping of the terraces within the contour-hedgerowsystem.