Litterfall mercury dry deposition in the eastern USA

Martin R. Risch; John F. DeWild; David P. Krabbenhoft; Randy Kolka; Leiming Zhang

doi:10.1016/j.envpol.2011.06.005

Treesearch

Litterfall mercury dry deposition in the eastern USA

Formally Refereed

Authors:

Martin R. Risch, John F. DeWild, David P. Krabbenhoft, Randy Kolka, Leiming Zhang

Year:

2012

Type:

Scientific Journal

Station:

Northern Research Station

DOI:

https://doi.org/10.1016/j.envpol.2011.06.005

Source:

Environmental Pollution. 161: 284-290.

Download (PDF 403 KB)

Download (PDF 403 KB): https://research.fs.usda.gov/download/treesearch/47067.pdf

Abstract

Mercury (Hg) in autumn litterfall frompredominately deciduous forestswas measured in 3 years of samples from 23 Mercury Deposition Network sites in 15 states across the eastern USA. Annual litterfall Hg dry depositionwas significantly higher (median 12.3 micrograms per square meter (µg/m²), range 3.5-23.4 µg/m²) than annual Hg wet deposition (median 9.6 µg/m², range 4.4-19.7 µg/m²). The mean ratio of dry to wet Hg deposition was 1.3-1. The sum of dry and wet Hg deposition averaged 21 µg/m² per year and 55% was litterfall dry deposition. Methylmercury was a median 0.8% of Hg in litterfall and ranged from 0.6 to 1.5%. Annual litterfall Hg and wet Hg deposition rates differed significantly and were weakly correlated. Litterfall Hg dry deposition differed among forest-cover types. This study demonstrated howannual litterfall Hg dry deposition rates approximate the lower bound of annual Hg dry fluxes.

Keywords

Mercury, Litterfall, Dry deposition, Wet deposition, Methylmercury

Citation

Risch, Martin R.; DeWild, John F.; Krabbenhoft, David P.; Kolka, Randall K.; Zhang, Leiming. 2012. Litterfall mercury dry deposition in the eastern USA. Environmental Pollution. 161: 284-290.