关键词: 底泥悬浮物, 黄鳍鲷, 稚鱼, 幼鱼, 致死效应

Abstract: Based on simulation experiments on changes in suspended sediment concentrations caused by de-silting, dredging and other maritime projects, this paper discusses levels of toxic effects of suspended sediment on Acanthopagrus latus. The results showed that certain effects were observed on juvenile A. latus when suspended sediment concentrations were higher than 40 mg/L, and lethal effects on juvenile A. latus increased notably as concentrations of suspended sediment grew higher and exposure to the sediment extended; on the Zhao’an side of Bachimen waters, the 96-hour LC50 on juvenile A. latus reached 8 111.30 mg/L, and on the Dongshan side of Bachimen waters, the 96-h LC50 on juvenile A. latus reached 21 849.52 mg/L. Prolonged exposure of suspended sediment could result in the adhesion of suspended particles on the body surface and gill filaments of young A. latus, causing shortness of breath and slowing growth in them. This might lead to chronic lethal effects as the cumulative fatality rate of young A. latus could reach 40.0%~42.5% after 30 days exposure to suspended sediment at a concentration of 160 mg/L. The present study showed that massive suspended sediment could have obvious lethal effects on A. latus. It could provide analytical basis for the effects on aquaculture from suspended sediment diffusion in maritime dredging projects.

Key words: suspended sediment, Acanthopagrus latus, juvenile A. latus, young A. latus, lethal effect