title: Phytoxicity of smelter-impacted soils in southwest Montana, USA.
abstract: A century of copper smelting in southwest Montana, USA, destroyed vegetation for many kilometers surrounding the Washoe Smelter. Once the vegetation was lost, exposed soils were subject to wind and water erosion, which removed topsoil and left soil surfaces paved with gravel. A greenhouse study was conducted using soils from smelter-impacted and non-smelter-impacted sites near Anaconda, Montana. Bluebunch wheatgrass, Agropyron spicatum (Pursh) Scribn., and western yarrow, Achillea lanulosa Nutt., were grown for 50 d in unamended, fertilized, or limed treatments to determine if soil fertility, pH, or trace elements were limiting plant growth on soil from the impacted site. The addition of fertilizer significantly increased plant biomass of both species in soils from impacted and nonimpacted sites when compared to unamended and limed soil. The addition of lime had no effect on plant growth. When plant growth in fertilized smelter-impacted soil was compared to unamended nonimpacted soil, significantly more plant biomass was observed in the fertilized smelter-impacted soil. Shoot and root concentrations of trace elements were higher in plants grown in impacted soil compared to nonimpacted soil. The only element that was found to occur in concentrations reported to be phytotoxic was arsenic (As). However, toxicity thresholds for As, reported in the literature, were generated in agricultural species and do not likely have application to the native perennials used in this study.
authors.affiliation: Rangeland Ecosystem Science Department, Colorado State University, Fort Collins 80523, USA. edr@cnr.colostate.edu
authors.forename: Edward F
authors.initials: EF
authors.lastname: Redente
authors.forename: Holley
authors.initials: H
authors.lastname: Zadeh
authors.forename: Mark W
authors.initials: MW
authors.lastname: Paschke
mesh_terms: D001151:Arsenic / Q000633:toxicity; D019659:Asteraceae / Q000254:growth & development*; D018533:Biomass; D003300:Copper; D005308:Fertilizers; D006863:Hydrogen-Ion Concentration; D007221:Industry; D018517:Plant Roots / Q000254:growth & development; D006109:Poaceae / Q000254:growth & development*; D012987:Soil; D012989:Soil Pollutants / Q000633:toxicity*; D014131:Trace Elements
chemical_list: D005308:Fertilizers; D012987:Soil; D012989:Soil Pollutants; D014131:Trace Elements; D003300:Copper; D001151:Arsenic