Abstract
Fossil fuel combustion is the primary anthropogenic source of both CO2 and Hg to the atmosphere. On a global scale, most Hg that enters ecosystems is derived from atmospheric Hg that deposits onto the land surface. Increasing concentrations of atmospheric CO2 may affect Hg deposition to terrestrial systems and storage in soils through CO2-mediated changes in plant and soil properties. We show, using free-air CO2 enrichment (FACE) experiments, that soil Hg concentrations are almost 30% greater under elevated atmospheric CO2 in two temperate forests. There were no direct CO2 effects, however, on litterfall, throughfall or stemflow Hg inputs. Soil Hg was positively correlated with percent soil organic matter (SOM), suggesting that CO2-mediated changes in SOM have influenced soil Hg concentrations. Through its impacts on SOM, elevated atmospheric CO2 may increase the Hg storage capacity of soils and modulate the movement of Hg through the biosphere. Such effects of rising CO2, ones that transcend the typically studied effects on C and nutrient cycling, are an important next phase for research on global environmental change.
Similar content being viewed by others
References
Andrews JA, Schlesinger WH (2001) Soil CO2 dynamics, acidification, and chemical weathering in a temperate forest with experimental CO2 enrichment. Global Biogeochem Cycles 15:149–162
Carpi A, Lindberg SE (1998) Application of a Teflon dynamic flux chamber for quantifying soil mercury flux: tests and results over background soil. Atmos Environ 32:873–882
DeLucia EH, George K, Hamilton JG (2002) Radiation-use efficiency of a forest exposed to elevated concentrations of atmospheric carbon dioxide. Tree Physiol 22:1003–1010
Ellsworth DS (1999) CO2 enrichment in a maturing pine forest: are CO2 exchange and water status in the canopy affected? Plant Cell Environ 22:461–472
Ericksen JA, Gustin MS, Schorran DE, Johnson DW, Lindberg SE, Coleman JS (2003) Accumulation of atmospheric mercury in forest foliage. Atmos Environ 37:1613–1622
Expert Panel on Mercury Atmospheric Processes (EPMAP) (1994) Mercury atmospheric processes: a synthesis report. Workshop Proceedings, EPRI/TR–104214, Tampa, FL
Filion M, Dutilleul P, Potvin C (2000) Optimum experimental design for free-air carbon dioxide enrichment (FACE) studies. Global Chang Biol 6:843–854
Finzi AC, Allen AS, DeLucia EH, Ellsworth DS, Schlesinger WH (2001) Forest litter production, chemistry, and decomposition following two years of free-air CO2 enrichment. Ecology 82:470–484
Fitzgerald WF, Lamborg CH (2003) Geochemistry of mercury in the environment. In: Holland HD, Turekian KK (eds) Treatise on geochemistry, vol 9. Elsevier, San Diego, pp 107–148
Fleck JA, Grigal DF, Nater EA (1999) Mercury uptake by trees: an observational experiment. Water Air Soil Pollut 115:513–523
Gabriel MC, Williamson DG (2004) Principal biogeochemical factors affecting the speciation and transport of mercury through the terrestrial environment. Environ Geochem Health 26:421–434
Grigal DF (2003) Mercury sequestration in forests and peatlands: a review. J Environ Qual 32:393–405
Gustin MS, Stamenkovic J (2005) Effect of watering and soil moisture on mercury emissions from soils. Biogeochemistry 76:215–232
Hendrey GR, Ellsworth DS, Lewin KF, Nagy J (1999) A free-air enrichment system for exposing tall forest vegetation to elevated atmospheric CO2. Global Chang Biol 5:293–309
Huynh H, Feldt LS (1976) Estimation of the Box correction for degrees of freedom from sample data in randomized block and split-plot designs. J Educ Stat 1:69–82
IPCC (2007) Climate change 2007: the physical scientific basis. In: Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt KB, Tignor M, Miller HL (eds) Contribution of Working Group I to the fourth assessment report of the Intergovernmental Panel on Climate Change. Cambridge University Press, New York, p 966
Iverfeldt A (1991) Mercury in forest canopy throughfall water and its relation to atmospheric deposition. Water Air Soil Pollut 56:553–564
Jastrow JD et al (2005) Elevated atmospheric carbon dioxide increases soil carbon. Global Chang Biol 11:2057–2064
Kolka RK, Nater EA, Grigal DF, Verry ES (1999) Atmospheric inputs of mercury and organic carbon into a forested upland bog watershed. Water Air Soil Pollut 113:273–294
Lamborg CH, Fitzgerald WF, Damman AWH, Benoit JM, Balcom PH, Engstrom DR (2002) Modern and historic atmospheric mercury fluxes in both hemispheres: global and regional mercury cycling implications. Global Biogeochem Cycles 16:1–51
Lichter J, Lavine M, Mace KA, Richter DD, Schlesinger WH (2000) Throughfall chemistry in a loblolly pine plantation under elevated atmospheric CO2 concentrations. Biogeochemistry 50:73–93
Lindberg SE, Hanson PJ, Meyers TP, Kim KH (1998) Air/surface exchange of mercury vapor over forests—the need for a reassessment of continental biogenic emissions. Atmos Environ 32:895–908
Loladze I (2002) Rising atmospheric CO2 and human nutrition: toward globally imbalanced plant stoichiometry? Trends Ecol Evol 17:457–461
Lovett GM, Nolan SS, Driscoll CT, Fahey TJ (1996) Factors regulating throughfall flux in a new New-Hampshire forested landscape. Can J For Res-Rev Can Rech For 26:2134–2144
Lubowski RN, Vesterby M, Bucholtz S, Baez A, Roberts MJ (2006) Major land uses in the United States. US Department of Agriculture economic information bulletin (EIB–14)
Millhollen AG, Obrist D, Gustin MS (2006) Mercury accumulation in grass and forb species as a function of atmospheric carbon dioxide concentrations and mercury exposures in air and soil. Chemosphere 65:889–897
Munthe J, Hultberg H, Lee YH, Parkman H, Iverfeldt A, Renberg I (1995) Trends of mercury and methylmercury in deposition, runoff water and sediments in relation to experimental manipulations and acidification. Water Air Soil Pollut 85:743–748
Norby RJ, Iversen CM (2006) Nitrogen uptake, distribution, turnover, and efficiency of use in a CO2-enriched sweetgum forest. Ecology 87:5–14
Norby RJ, Todd DE, Fults J, Johnson DW (2001) Allometric determination of tree growth in a CO2-enriched sweetgum stand. New Phytol 150:477–487
Norby RJ, Sholtis JD, Gunderson CA, Jawdy SS (2003) Leaf dynamics of a deciduous forest canopy: no response to elevated CO2. Oecologia 136:574–584
Oh NH, Richter DD (2004) Soil acidification induced by elevated atmospheric CO2. Global Chang Biol 10:1936–1946
Rasmussen PE (1995) Temporal variation of mercury in vegetation. Water Air Soil Pollut 80:1039–1042
Rasmussen PE, Mierle G, Nriagu JO (1991) The analysis of vegetation for total mercury. Water Air Soil Pollut 56:379–390
Rea AW, Keeler GJ, Scherbatskoy T (1996) The deposition of mercury in throughfall and litterfall in the Lake Champlain watershed: a short-term study. Atmos Environ 30:3257–3263
Rea AW, Lindberg SE, Keeler GJ (2001) Dry deposition and foliar leaching of mercury and selected trace elements in deciduous forest throughfall. Atmos Environ 35:3453–3462
Rea AW, Lindberg SE, Scherbatskoy T, Keeler GJ (2002) Mercury accumulation in foliage over time in two northern mixed-hardwood forests. Water Air Soil Pollut 133:49–67
Riggs JS, Tharp ML, Norby RJ (2007) ORNL FACE weather data. Carbon Dioxide Information Analysis Center, US Department of Energy, Oak Ridge National Laboratory, Oak Ridge
Satterthwaite FE (1946) An approximate distribution of estimates of variance components. Biometrics 2:110–114
Schroeder WH, Munthe J (1998) Atmospheric mercury—an overview. Atmos Environ 32:809–822
Schuster E (1991) The behavior of mercury in the soil with special emphasis on complexation and adsorption processes—a review of the literature. Water Air Soil Pollut 56:667–680
St Louis VL et al (2001) Importance of the forest canopy to fluxes of methyl mercury and total mercury to boreal ecosystems. Environ Sci Technol 35:3089–3098
US Environmental Protection Agency (US EPA) (1997a) Mercury study report to Congress, vol. VII. Characterization of human health and wildlife risks from mercury exposure in the United States, EPA-452/R-97-009
US Environmental Protection Agency (US EPA) (1997b) Mercury study report to Congress, vol. III. Fate and transport of mercury in the environment, EPA-452/R-97-005
Whelan MJ, Anderson JM (1996) Modelling spatial patterns of throughfall and interception loss in a Norway spruce (Picea abies) plantation at the plot scale. J Hydrol 186:335–354
Wullschleger SD, Gunderson CA, Hanson PJ, Wilson KB, Norby RJ (2002) Sensitivity of stomatal and canopy conductance to elevated CO2 concentration—interacting variables and perspectives of scale. New Phytol 153:485–496
Yin YJ, Allen HE, Li YM, Huang CP, Sanders PF (1996) Adsorption of mercury(II) by soil: effects of pH, chloride, and organic matter. J Environ Qual 25:837–844
Acknowledgements
We thank D. Richter for soil samples, E. A. Leger and F. J. Rohlf for statistical advice, C. Iversen, R. Oren and the FACE staff for field support, J. Lichter for conversations and data on pre-treatment soils, R. K. Kolka for advice on stemflow collectors, S. Lindberg and N. Bloom for throughfall sampling advice, J. Varekamp for use of his DMA-80, W. Schlesinger for advice during manuscript preparation, and H. Heilmeier and two anonymous reviewers for comments on this manuscript. This work was supported by the US Department of Energy, Office of Science-Biological and Environmental Research, and fellowships from the National Science Foundation (S. M. N.) and Department of Energy (S. M. N.).
Author information
Authors and Affiliations
Corresponding author
Additional information
Communicated by Hermann Heilmeier.
Rights and permissions
About this article
Cite this article
Natali, S.M., Sañudo-Wilhelmy, S.A., Norby, R.J. et al. Increased mercury in forest soils under elevated carbon dioxide. Oecologia 158, 343–354 (2008). https://doi.org/10.1007/s00442-008-1135-6
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00442-008-1135-6