A contribution to the environmental biology of mercury accumulation in plants

Abstract

Samples of six common plant species collected in the old mining areas near Prince George, British Columbia (Canada) and Mount Amiata, Tuscany (Italy) show remarkable similarities in the variation of plant/soil Hg concentration ratio with soil Hg content irrespective of species or other biological differences. In contrast, plants sampled in the geothermally active areas of New Zealand, Hawaii and around Mount St. Helens exhibit more individuality in the concentration ratio to soil Hg relationship, but the relationships are distinctly different from the mine site specimens. This distinction is particularly evident when the same species of Equisetum and Plantago taken from these two different areas are compared. These and other data support the hypothesis that specific local environmental factors strongly influence the accumulation of Hg in plants even when the immediate soil concentrations are the same. Our findings show that some plants contain concentrations of total Hg as high as 5500 to 14000 Ixg kg-~ (dw). Experimental STUDY SITES AND PLANTSThe Cominco Hg mine at Fort St. James and the nearby city of Prince George have been described (Johnston et aL, 1975;

Mercury in vegetation and soils at abandoned mercury mines in southwestern Alaska, USA

“…7) reveal higher proportions of Hg in the plants in the retort and background areas. Mercury accumulation in vegetation is the result of Hg volatilization (evasion) from soil and subsequent absorption through the stomata (Lindberg et al 1979;Du & Fang 1982;Siegal et al 1987;Godbold & Hütterman 1988), dry deposition of reactive Hg species from the atmosphere (Lindberg et al 1991;Lindberg 1996;Rea et al 2001) or transpiration of dissolved gaseous Hg species [(Hg(0) or Hg(II)] from the soil solution (Hanson et al 1995;Lindberg 1996;Benesch et al 2001;Graydon et al 2001;Lindberg & Meyers 2001;Rea et al 2002). The higher plant/soil total-Hg concentration ratios in the background and retort areas have the highest proportion of reactive Hg species, such as gaseous Hg(II), that likely resulted from atmospheric deposition and retort emissions.…”

Evaluation of mercury uptake and distribution in Vicia sativa L. applying two different study scales: Greenhouse conditions and lysimeter experiments

“…Although roots act as a barrier to this translocation; part of this metal can be translocated to the shoot (Patra and Sharma, 2000). This fact could be due to the binding formation between this metal and the carboxylic groups in the root cell wall (Beauford et al, 1976;Siegel et al, 1987). According to this tendency, the results show that mercury concentration in roots is always significantly higher than in the rest of the plant fractions and applying the Fisher LSD test (α = 0.05), there is up to 7.6 times more mercury in the root than in the shoot.…”

Temporal and spatial distribution and production of dissolved gaseous mercury in the Bay St. François wetland, in the St. Lawrence River, Quebec, Canada

“…Rooted submerged aquatic plants, for instance, can release oxygen from root surfaces (Armstrong and Armstrong, 1990), potentially favoring oxidation of reduced metallic ions. Floating macrophytes, in turn, can reduce ionic Hg to Hg(0) (Siegel et al, 1987).…”