Development of an autonomous Niskin sampler for quantitative estimation of graded-grain flux and bottom-sediment change

Abstract

An autonomous Niskin sampler was developed with special purpose of reliable in-situ calibration of turbidity meters and quantitative monitoring of sediment flux. It was tentatively designed for isokinetic sampling in order to prevent the difference in the concentration and grain size composition of sampled suspension and those of in-situ suspension. Mooring and installation of the new samplers can provide information on the temporal variation of suspended-particle composition. Its performance of isokinetic sampling has been confirmed through field applications, and will serve as a useful tool for various fields of coastal engineering and oceanography.