Field methods for measurement of fluvial sediment

Abstract

This report describes equipment and procedures for collection and measurement of fluvial sediment.The complexity of the hydrologic and physical environments and man's ever-increasing data needs make it essential for those responsible for the collection of sediment data to be aware of basic concepts involved in processes of erosion, transport, deposition of sediment, and equipment, and procedures necessary to representatively sample and measure sediment data.In addition to an introduction, the report has two major sections.The "Sediment-Sampling Equipment" section encompasses discussions of characteristics and limitations of various models of depth-and point-integrating samplers, single-stage samplers, bed-material samplers, bedload samplers, automatic-pumping samplers, and support equipment.The "Sediment-Sampling Techniques" section includes discussions of representative sampling criteria, characteristics of sampling sites, equipment selection relative to the sampling conditions and needs, depth-and point-integration techniques, surface and dip sampling, determination of transit rates, sampling programs and related data, cold-weather sampling, bed-material and bedload sampling, measuring total sediment discharge, and reservoir sedimentation rates.1. To allow water to enter the nozzle isokinetically.(In isokinetic sampling, water approaching the nozzle undergoes no change in speed or direction as it enters the orifice.)