Sedimentary processes, metal enrichment and potential ecological risk of metals in lacustrine sediments of Svalbard, Arctic

Abstract

The Svalbard archipelago is a glacial environment bestowed with various lakes that act as a natural archive for understanding environmental conditions. The accumulation of sediments in lake basins and their distribution are affected by different mechanisms. Therefore, to understand the distribution of sediments, factors controlling the transport and metal enrichment in the lake environment, core sediments were studied from four lakes (L-A, L-1, L-2 and L-3). Also, the potential ecological risk index (PERI) was computed to determine the impact of metal enrichment on the sediment-associated biota. The results obtained showed that the distribution of trace elements was mainly controlled by the major elements like Al, Ti, Fe, and Mn attributed to their lithogenic origin. Index of geoaccumulation (I sub(geo)) of all four lakes showed a moderate level of enrichment of metals like Cr and Cd indicating an enhanced supply of these metals probably from the catchment rocks and anthropogenic activities. A comparison of metals with Arctic Sediment Quality Guidelines (ASQGs) showed that Cd, Cr and Cu were enriched in the sediments of all the cores indicating the occurrence of adverse biological effects. Furthermore, a potential ecological risk index (PERI) revealed high Cd indicating considerable potential ecological risk to the sediment-associated biota. Thus, trace element influx to the lakes needs to be monitored with due emphasis on Cd contamination.