EVALUATION OF SEDIMENT TRAPS IN LAKE ST CLAIR, LAKE-ONTARIO, AND HAMILTON HARBOR

Sediment traps are simple, inexpensive devices that yield time-integrated samples of material suspended in the water column. Although many different designs have been proposed, there seems to be general agreement that the cylindrical settling tube is a design capable of yielding quantitative results in relatively calm waters. The reliability of these or any other trap in shallow water with significant wave orbital motions is unknown. This paper describes our attempts to assess the field performance of conventional settling tubes and two versions of horizontally-ported chambers in shallow, wave-dominated water. We find that catch rates of the horizontally-ported chambers correlate strongly and positively with the root mean square horizontal flow velocity over the trapping interval. We suspect a similar dependence exists for the settling tubes. With present levels of understanding, results from sediment traps of these designs deployed in shallow, wave-dominated water should be given qualitative status only. © 1990, International Association for Great Lakes Research. All rights reserved.