A comparison of various ecological indexes for environmental assessment of vulnerable mountain ecosystems

Abstract

The aim of this work was to compare various ecological indexes to assess the state of urbanized ecosystems of the Issyk-Kul region in the Kyrgyz Republic. Soil samples were analyzed for Pb, Zn, Fe, Cu and Cd using AAS. Heavy metal contamination status was assessed using indexes for enrichment factor, geo accumulation, contamination factor, degree of contamination, pollution load, potential ecological risk and integrated risk using the Triad approach. Results show marked variations of heavy metal concentrations within the study area. The concentrations of heavy metals in soils of Issyk-Kul had the following increasing order: Zn> Pb> Cu> Cd. Indexes such as enrichment factor and contamination factor showed the Issyk-Kul soils to be moderately polluted with Pb, Zn and Cd; geoacumulation revealed extreme contamination with Pb, Zn and Cu. Potential ecological risk estimated low risk, while the Triad approach characterized soil as highly contaminated. The Triad approach shows that using biotic components in evaluating the contamination degrees is informative. The results of this study show that adequate measures should be put to checkmate and regulate human activities around Issyk-Kul Lake in order to protect soil from further deterioration and contamination.