Mercury export from the Yukon River Basin and potential response to a changing climate

Environmental Science & Technology
By: , and 

Links

Abstract

We measured mercury (Hg) concentrations and calculated export and yield from the Yukon River Basin (YRB) to quantify Hg flux from a large, permafrost-dominated, high-latitude watershed. Exports of Hg averaged 4400 kg Hg yr-1. The average annual yield for the YRB during the study period was 5.17 μg m-2 yr-1, which is 3–32 times more than Hg yields reported for 8 other major northern hemisphere river basins. The vast majority (90%) of Hg export is associated with particulates. Half of the annual export of Hg occurred during the spring with about 80% of 34 samples exceeding the U.S. EPA Hg standard for adverse chronic effects to biota. Dissolved and particulate organic carbon exports explained 81% and 50%, respectively, of the variance in Hg exports, and both were significantly (p < 0.001) correlated with water discharge. Recent measurements indicate that permafrost contains a substantial reservoir of Hg. Consequently, climate warming will likely accelerate the mobilization of Hg from thawing permafrost increasing the export of organic carbon associated Hg and thus potentially exacerbating the production of bioavailable methylmercury from permafrost-dominated northern river basins.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Mercury export from the Yukon River Basin and potential response to a changing climate
Series title Environmental Science & Technology
DOI 10.1021/es202068b
Volume 45
Issue 21
Year Published 2011
Language English
Publisher ACS Publications
Publisher location Washington, D.C.
Contributing office(s) Mercury Research Laboratory, Branch of Regional Research-Central Region, Toxic Substances Hydrology Program
Description 6 p.
First page 9262
Last page 9267
Country United States
State Alaska
Other Geospatial Yukon River Basin