CONCENTRATIONS OF CD, PH, ZN AND CN IN PRISTINE WETLANDS OF THE RUSSIAN ARCTIC

Background concentrations of Cd, Pb, Zn and Cu were studied for wetlan ds from pristine regions of the Russian Arctic: Severnaya Zemlya Archi pelago, Vrangel Island, Arctic deserts and tundra of the North Taimyr Peninsula, Byrranga Mountainous Area, tundra zone of Mid-Siberia, Nort h-East Siberia, Far North-East, and Amguemo-Anadyr Mountainous Area. T hese wetland regions were known to be relatively remote and isolated, with little human population and no local industry. Samples were colle cted during the period 1976-1993 and included: (a) snow and thaw water , (b) particulate matter, (c) bottom sediments, (d) hydric organo-mine ral deposits and hydric soils, (e) polygonal bog peat and sedge-moss p eat, Observed ranges for the background concentrations of Cd, Pb, Zn, and Cu in water were 0.001-0.15, 0.02-0.36, 0.05-2.9 and 0.23-6.2 mu g l(-1) respectively. For (b)-(e) the corresponding values were [0,04-0 .46; 1.3-41; 8.6-190; 0.7-63]; [0.05 0.99; 1.5-49; 2.5-153; 2.4-55]; [ 0.05-0.96; 1.7-44; 2.2-154; 2.0-82] and [0.03-0.83; 1.3-31; 2.1-124; 1 .7-68] mg kg(-1), dry wt, respectively. Although full assessment of th e pristine nature of the wetlands was not possible due to the limited data available, the observed metal concentrations reflect natural geoc hemical background levels and influence from localized minor ore-depos its present for some regions. In general, there was no evidence of imp act from remote industrial regions of the Russian Arctic. (C) 1997 Els evier Science Ltd. All rights reserved.