Changes in the long-term supply of mercury species to the upper mixed waters of a recovering lake

Svetoslava G. Todorova, Charles T. Driscoll, Steven W. Effler, Susan O'Donnell, David A. Matthews, Dimitar L. Todorov, Stephanie Gindlesperger

Research output: Contribution to journalArticle

12 Scopus citations

Abstract

We quantified internal processes that supply methylmercury from hypolimnetic reducing zones to the upper waters of a Hg-contaminated lake, Onondaga Lake, NY, USA. Diffusive transport continuously supplied methylmercury to the epilimnion under summer stratification, while fall mixing resulted in a pulsed release of methylmercury to the upper mixed waters. These processes were the main internal sources of methylmercury to the epilimnion, and together almost equaled the total external supply. The wind-driven entrainment represented an additional stochastic internal supply of methylmercury of approximately 9% in 2006. Considering more than 15 years of data, we estimate 1.8 wind-driven events occur per year. The mass of methylmercury inputs to the epilimnion exceeded the measured increase, suggesting that loss processes are important in regulating methylmercury accumulation. The relative contribution of internal sources of methylmercury to the epilimnion has decreased in recent years, shifting the importance to the external inputs.

Original languageEnglish (US)
Pages (from-to)314-321
Number of pages8
JournalEnvironmental Pollution
Volume185
DOIs
StatePublished - Feb 2014

Keywords

  • Diffusive mixing
  • Entrainment
  • Methyl mercury
  • Onondaga Lake
  • Turnover

ASJC Scopus subject areas

  • Toxicology
  • Pollution
  • Health, Toxicology and Mutagenesis

Fingerprint Dive into the research topics of 'Changes in the long-term supply of mercury species to the upper mixed waters of a recovering lake'. Together they form a unique fingerprint.

  • Cite this