DISTRIBUTION OF MAJOR AND TRACE-ELEMENTS IN SEDIMENTS AND PORE-WATER OF LAKE ERIE

Concentration profiles of major and trace elements were determined in sediment cores from the Central Basin of Lake Erie. The concentrations of trace Elements (As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn) in the sed iments were greatest at approximately 18 cm sediment depth, correspond ing to the early 1960s. The concentrations of all elements in the sedi ments have considerably decreased in the last decade. However, the con centrations of Hg, Pb, and Cd are still about 10, 5, and 4 times great er, respectively, than those iii the pre-industrial sediments. The pro files of dissolved concentrations of the trace ele ments in pore water were characterized by maxima below the sediment-water interface, drop ping off rapidly within the zone of reduced sediments. Concentrations of dissolved trace elements below the sediment-water interface are abo ut one order of magnitude greater than those in the lake water Conserv ative estimates of benthic fluxes ranged from 0.04 mu g/cm(2).y to 194 mu g/cm(2).y for Cd and Fe, respectively. Upward diffusive remobiliza tion from sediments to lake water is a significant transport process i n the Central Basin of Lake Erie and may play an important role in the transport of trace elements front the sediments.