RiskassessmentofheavymetalinsedimentsofYangzonghailakeenvironment,China

Zhang yuxi，Liu jingtao，Zhang ying

Abstract

The concentrations of 10 heavy metals in sediments of Yangzonghai Lake in Yunnan, China were analyzed. Ecological risk index presented by H?kanson to assess the potential ecological risk of Yangzonghai Lake was utilized. The results showed that the mean concentrations of titanium, manganese, zinc, vanadium, chromium, copper, nickel, cobalt, lead and arsenic in surface sediments were up to 9413.1, 617.9, 149.2, 189.6, 145.8, 97.6, 55.1, 27.4, 40.3 and 31.4mg/kg, respectively, which are higher than their natural background values. Pearson’s correlation analysis indicated that zinc, chromium, lead and arsenic were highly correlated, and they were originate from activities. Titanium, manganese, vanadium, copper, nickel, and cobalt were also well correlated and mainly from natural factors. The evaluation of pollution index revealed a clear accumulation of the 10 heavy metals, all reaching the level of moderate pollution. Enrichment of arsenic, copper, and chromium was more prominent then other heavy metals. Heavy metals in Yangzonghai Lake in the descending order of their ecological risks were arsenic, copper, cobalt, nickel, lead, chromium, vanadium, zinc, manganese and titanium. Among them, arsenic was the most prominent factor of ecological risk in surface sediment of Yangzonghai Lake.