Mercury Sequestration in Forests and Peatlands
- 1 March 2003
- journal article
- review article
- Published by Wiley in Journal of Environmental Quality
- Vol. 32 (2), 393-405
- https://doi.org/10.2134/jeq2003.3930
Abstract
Nearly all Hg in vegetation is derived directly from the atmosphere. Mass of Hg in forest vegetation (roughly 0.1 mg m−2) is about an order of magnitude smaller than that in the forest floor (1 mg m−2) and two orders of magnitude smaller than that in the mineral soil (10 mg m−2). Mass of Hg in peat (20 mg m−2) is greater than the sum of that in mineral soil and the forest floor; wetlands usually sequester more Hg than associated uplands. The strong relationship of Hg to organic matter, associated with binding by reduced S groups, is fundamental to understanding Hg distribution and behavior in terrestrial systems. The stoichiometry of the Hg–C relationship varies; Hg–S relationships, though less variable, are not constant. Because of the Hg–organic matter link, landscape conditions that lead to differential soil organic matter accumulation are likely to lead to differential Hg accumulation. The ratio of methylmercury (MeHg) to total Hg is generally low in both vegetation (near 1.5%) and soil (<1%), but areas of poorly drained soils and wetlands are sites of MeHg production. The annual emission of anthropic Hg from the 48 contiguous states of the USA (144 Mg) is two orders of magnitude less than the pool of Hg in forests of those states (30 300 Mg). Peatlands, less than 2% of total land area, sequester more than 20 times annual emissions (2930 Mg). If global climate change affects C storage it will indirectly affect Hg storage, having a major effect on the balance between emissions and sequestration and on the global Hg cycle. Copyright © 2003. American Society of Agronomy, Crop Science Society of America, Soil Science Society . Published in J. Environ. Qual.32:393–405.Keywords
Funding Information
- Electric Power Research Institute (EP-P2300/C1033)
This publication has 78 references indexed in Scilit:
- Temporal variation of mercury in vegetationWater, Air, & Soil Pollution, 1995
- Methylmercury output from the Svartberget Catchment in northern Sweden during spring floodWater, Air, & Soil Pollution, 1995
- Foliar exchange of mercury vapor: Evidence for a compensation pointWater, Air, & Soil Pollution, 1995
- Mechanisms of deposition of methylmercury and mercury to coniferous forestsWater, Air, & Soil Pollution, 1995
- Sources of methyl mercury to freshwater ecosystems: A reviewWater, Air, & Soil Pollution, 1995
- Impacts of mercury contamination in the southeastern United StatesWater, Air, & Soil Pollution, 1995
- The methylmercury to total mercury ratio in selected marine, freshwater, and terrestrial organismsWater, Air, & Soil Pollution, 1995
- Current Methods of Estimating Atmospheric Mercury Fluxes in Remote AreasEnvironmental Science & Technology, 1994
- Pinusas an atmospheric hg biomonitorEnvironmental Technology, 1991
- Coarse Woody Debris in Douglas‐Fir Forests of Western Oregon and WashingtonEcology, 1988