Sediment Traps for Measuring Onslope Surface Sediment Movement


Book Description

Two types of small (30-cm aperture) sheet metal sediment traps were developed to monitor onslope surface sediment transport. Traditionally, sediment traps and erosion pins have been used to measure the onslope movement of surficial soil material. While pins may be appropriate for documentinglandscapedenudation, traps aremoresuitable for monitoring downslope transport parallel to the ground surface. Previous investigations used large (3-m aperture) traps to measure sediment transport. However, large aperture traps are cumbersome and require excessive amounts of time and energy for installation, sample collection, and sample processing. These serious logistical constraints make data acquisition difficult and expensive. The small traps were designed to remedy this situation. Reld tests of these small traps revealed variable patterns of spatial and temporal surficial debris movement obscured in previous studies. Although these traps are not without limitations, the improved sampling logistics allow greater sample sizes andconstituteamarkedimprovement over other transport measurement techniques.