Abstract
Purpose
Understanding the potential activation mechanisms and Hg transfer pathways is key to providing a basis for developing effective measures to prevent soil Hg from entering the food chain and dispersing into the environment. Besides acidification, the presence of natural complexing or chelating agents in the environment may also assist or intensify this process. The objective of this research is to understand the mechanisms behind the interaction of Hg with the complexity of humus material and other soil constituents with regards to plant uptake.
Materials and methods
Cultivation experiments with Basella alba were carried out to determine the effects of humus on the plant uptake of Hg bound by five pure mineral samples and five different soil types as well as ionic Hg in Hg(NO3)2 solution.
Results and discussion
Among all the tested forms of Hg uptake by B. alba, soluble inorganic Hg was found to be the most bioavailable. Without humus added, Hg bioavailability from the mineral substrates increased with the pHzpc of the mineral. The addition of humus can either suppress or promote Hg bioavailability depending on the mineral or soil type. Fulvic acid is the most active agent for Hg bound to ferric and manganese oxides or soils which contain high concentrations of these phases. Humic acids, particularly brown humic acid, tend to promote Hg bioavailability bound by pure bentonite and soils containing abundant 2:1 montmorillonite-type clays. The effect of gray humic acid is consistently weaker than brown humic acid for Hg bound by all mineral and soil forms examined in this study. The effect of a particular humus fraction on Hg bioavailability is related to its ability to convert Hg bound by solid phases into soluble complexes as well as the stability of the complexes that form.
Conclusions
Soluble inorganic Hg is the most bioavailable form for plant uptake. A mineral’s pHzpc plays an important role in determining Hg bioavailability bound by pure mineral substrates. The addition of humus can either suppress or promote Hg bioavailability depending on the mineral or soil type. The effect of a particular humus fraction on Hg bioavailability is related to its ability to convert Hg bound by solid phases into soluble complexes as well as the stability of the complexes that form. The higher the complex capacity and the lower the complex stability of the humus with Hg, the greater is its ability to enhance the bioavailability of Hg bound by soil minerals.
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References
Barren E, Foust DF (1996) Mercury in vegetation. General electric company report. #96CRD099. 10pp
Beauford W, Barber J, Barringer AR (1977) Uptake and distribution of mercury within higher plants. Physiol Plant 39:261–265
Bergkvist P, Jarvis N (2004) Modeling organic carbon dynamics and cadmium fate in long-term sludge-amended soil. J Environ Qual 33:181–191
Blaylock MJ, Salt DE, Dushenkov S, Zakharova O, Gussman C, Kapulnik Y, Ensley BD, Raskin I (1997) Enhanced accumulation of Pb in Indian mustard by soil applied chelating agents. Environ Sci Technol 31:860–865
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
Chaney RL, Malik M, Li YM, Brown SL, Brewer ER, Angle JS, Baker MAJ (1997) Phytoremediation of soil metals. Curr Opin Biotechnol 8:279–284
Chapman PM, Allen HE, Godtfredsen K, Graggen MNZ (1996) Evaluation of bioaccumulation factors in regulating metals. Environ Sci Technol 30:448–452
Collins RN, Merrington G, Mclaughlin MJ, Morel JL (2003) Organic ligand and pH effects on isotopically exchangeable cadmium in polluted soils. Soil Sci Soc Am J 67:112–121
Devolder PS, Brown SL, Hesterberg D, Paudya K (2003) Metal bioavailability and speciation in a wetland tailings repository amended with biosolids compost, wood ash and sulfate. J Environ Qual 32:851–864
Driscoll CT, Blette U, Yan C, Schofield CL, Munsn RR, Holsapple R (1995) The role of dissolved organic carbon in the chemistry and bioavailability of Hg in remote Adirondack Lakes. Water Air Soil Pollut 80:499–508
Du SH, Fang SC (1982) Uptake of elemental mercury vapor by C3 and C4 species. Environ Exp Bot 22:437–443
Granato TC, Pietz RI, Gschwind J, Lue-Hing C (1995) Mercury in soils and crops from fields receiving high cumulative sewage sludge application: validation of U.S.EPA’s risk assessment for human ingestion. Water Air Soil Pollut 80:1119–1127
Green-Pedersen H, Pind N (2000) Preparation, characterization, and sorption properties for Ni(II) of iron oxyhydroxide–montmorillonite. Colloids Surf A Physicochem Eng Asp 168:133–145
Grigg RB (2003) Improving CO2 efficiency for recovering oil in heterogeneous reservoirs. Annual technical progress report doe contract no. DE-FG26-01BC15364, 90pp
Gustin MS, Ericksen JA, Johnson DW, Lindberg SE, Coleman JS (2004) Application of controlled mesocosm for understanding mercury plant–soil–air exchange. Environ Sci Technol 38:6044–6050
Hanson PJ, Lindberg SE, Tabberer TA, Owens JG, Kim KH (1995) Foliar exchange of mercury vapor: evidence for a compensation point. Water Air Soil Pollut 80:373–382
Hatzinger PB, Alexander M (1995) Effect of aging of chemicals in soil on their biodegradability and extractability. Environ Sci Technol 29:537–545
Hoagland DR, Arnon DI (1950) The water-culture method for growing plants without soil. Calif Agric Experiment Stat Circ 347:32
Johnson SE, Herman JS, Mills AL, Hornberger GM (1999) Bioavailability and desorption characteristics of aged nonextractable atrazine in soil. Environ Toxicol Chem 18:1747–1754
Li QK (1989) Soil agrochemistry conventional analysis methods. Science, Beijing
Lindberg SE, Price J (1999) Measurements of the airborne emission of mercury from municipal landfill operations: a short-term study in Florida. J Air Waste Manage Assoc 49:174–185
Loring DH (1982) Geochemical factors controlling the accumulation and dispersal of heavy metals in Bay of Fundy sediments. Can J Earth Sci 19:930–944
Madsen EL (1991) Determining in situ biodegradation. Environ Sci Technol 25:1663–1673
Martinez CE, McBride MB (2001) Cd, Cu, Pb and Zn coprecipitates in Fe oxide form at different pH; aging effects on metal solubility and extractability on citrate. Environ Toxicol Chem 20:122–126
McBride MB (1994) Chemistry of soils. Oxford University Press, New York
McGraph SP, Knight B, Killham K, Preston S, Paton GI (1999) Assessment of the toxicity of metals in soils amended with sewage sludge using a chemical technique and a lux-based biosensor. Environ Toxicol Chem 18:659–663
McNab NJ, Hughes JC, Howard JR (1997) Pollution effects of wastewater sludge application to sandy soils with particular reference to the behavior of mercury. Appl Geochem 12:321–325
Mierle G, Ingram R (1991) The role of humic substances in the mobilization of mercury from watersheds. Water Air Soil Pollut 56:349–357
Mosbæk H, Tjell JC, Sevel T (1988) Plant uptake of airborne mercury in background areas. Chemosphere 17:1227–1236
Nelson A, Donkin P (1985) Process of bioaccumulation: the importance of chemical speciation. Mar Pollut Bull 16:164–169
Pang SW, Qiu GK, Sun JF (1981) Sequential chemical extraction for determining the Hg forms in sediment. Acta Scientiae Circumstantiae 1:234–241
Qing CL, Mu SS (1995) Preventing the soil mercury entering terrestrial food chain. Acta Scientiae Circumstantiae 5:148–155
Reed BE, Vaughan R, Jiang L (2000) As(III), As(V), Hg, and Pb removal by Fe-oxide impregnated activated carbon. J Environ Eng 126(9):869–873
Stacey S, Merrington G, Mclaughlin MJ (2001) The effect of aging biosolids on the availability of cadmium and zinc in soil. Europ J Soil Sci 52:313–321
Stevenson FJ (1994) Humus chemistry, 2nd edn. Wiley, New York
Stumm W, Morgan JJ (1995) Aquatic chemistry, chemical equilibria and rates in natural waters, 3rd edn. Wiley, New York, p 1022
United States National Research Council (2003) Committee on bioavailability of contaminants in soils and sediments: processes, tools and applications. National Academies, Washington, DC, p 432
Vangronsveld J, Cunningham SD (1998) Metal-contaminated soils: in situ inactivation and phytorestoration. Springer, New York, 265 pp
Wallschlager D, Desai MV, Spengler MM, Wilken RD (1998a) Mercury speciation in floodplain soils and sediments along a contaminated river transect. J Environ Qual 27:1034–1043
Wallschlager D, Desai MV, Spengler MM (1998b) How humic substances dominate mercury geochemistry in contaminated floodplain soils and sediments. J Environ Qual 27:1044–1054
Warman PR, Muizelaar T, Termeer WC (1995) Bioavailability of As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se, and Zn from biosolids amended compost. Compost Sci Util 3:40–50
Wilhelm S (2001) An estimate mercury emissions to the atmosphere from petroleum. Environ Sci Technol 35:4701–4704
Williams DE, Viamis J, Pukite AH, Korey JE (1985) Metal movement in sludge treated soils after 6 years of sludge addition: 2. Nickle, cobalt, iron, manganese, chromium and mercury. Soil Sci 140:120–125
Yao AJ, Qing CL, Mu SS, Reardon EJ (2006) Effects of humus on the environmental activity of mineral-bound Hg: influence on Hg volatility. Appl Geochem 21(3):446–454
Yin Y, Allen HE, Li Y, Huang CP, Sanders PF (1996) Adsorption of mercury(II) by soils: effect of pH, chloride and organic matter. J Environ Qual 25:257–261
Acknowledgments
The project was supported by the NSFC-Guangdong Joint Foundation of China (No. U0833004).
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Yao, A., Qiu, R., Qing, C. et al. Effects of humus on the environmental activity of mineral-bound Hg: influence on Hg plant uptake. J Soils Sediments 11, 959–967 (2011). https://doi.org/10.1007/s11368-011-0370-3
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DOI: https://doi.org/10.1007/s11368-011-0370-3