FLUXES OF CU, PB AND MN TO THE NORTHEASTERN IRISH-SEA - THE IMPORTANCE OF SEDIMENTAL AND ATMOSPHERIC INPUTS

The concentrations of dissolved and particulate Cu, Fe, Mn and Pb have been determined in four cores obtained from the north-eastern Irish S ea. The diffusional fluxes of Cu, Ph and Mn from the sediments have be en estimated from the concentration gradients between the porewaters a nd the overlying seawater The concentrations of Cu, Pb and Mn in marin e aerosols and rainwater have been obtained from a long-term collectio n campaign and used to determine their atmosphere-coastal ocean fluxes , The results show that of the total inputs (from rivers, direct waste s, dumping, atmospheric deposition and sediment-water exchange), the a tmospheric component constitutes about 6% of the total Cu input, where as sediment-water fluxes contribute about 34%. For Pb the atmospheric input is 3% and the flux from the sediments is 29%. The amounts of Cu and ph diffusing from the coastal sediments are similar to the sum of the quantities entering via the rivers and direct waste inputs from in dustrial and domestic sources, These estimates of metal fluxes have im portant consequences for the long-term environmental health of the Iri sh Sea. (C) 1998 Elsevier Science Ltd. AIL rights reserved.