Response of mercury accumulation to anthropogenic pollution in the past 1000 years based on Lake Huguangyan sediments, Southern China

A new Pb-210-dated record of Hg accumulation derived from a sediment core from a Hg-enriched area in Huguangyan Lake (HGY) in South China is presented. Based on synthetic analyses of multi-proxy records including chemical composition, total organic matter, and grain-size distribution in surface sediments and nearby soil samples, it is inferred that the influx of Hg into the lake is mainly a result of atmospheric deposition, with no or minor hydroclimate-induced lithogenic input from the catchment and limited adsorption effects of organic matter and clay. Significantly enhanced anthropogenic input of Hg started in the early 1900s. Since then, several anomalies of Hg accumulation have been the results of wars or intensified economic activities in China. HGY sediments provide a rare and reliable natural archive for detecting atmospheric Hg deposition, which is closely related to anthropogenic activities.

Automated summary

The new Pb-210-dated record of Hg accumulation in the Huguangyan Lake (HGY) sediment core from a Hg-enriched area in South China suggests that atmospheric deposition is the main source of Hg influx into the lake, with minimal input from the catchment and limited adsorption effects of organic matter and clay. Enhanced anthropogenic input of Hg began in the early 1900s, correlating with wars or increased economic activities in China. The HGY sediments serve as a valuable natural archive for studying atmospheric Hg deposition related to human activities.