U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting Charleston South Carolina March 8-12,1999--Volume 1 of 3--Contamination From Hard-Rock Mining, Water-Resources Investigation Report 99-4018A

Representative Plant and Algal Uptake of Metals near Globe, Arizona

By Justin C. Marble, Timothy L. Corley, and Martha H. Conklin

This report is available in pdf format: Marble.pdf 227KB

ABSTRACT

Past acid-mining activities in the Globe-Miami, Arizona area have resulted in the release of metal contaminants into the perennial reach of Pinal Creek. Dissolved manganese (Mn(II)) is the dominant metal with lower concentrations of dissolved zinc (Zn(II)), nickel (Ni(II)), copper (Cu(II)), iron (Fe(II,III)), and cobalt (Co(II)). In this study, uptake of metals by plants along the perennial reach of Pinal Creek was measured. Specifically, water speedwell (Veronica anagallis-aquatica), rabbitfoot grass (Polypogon monspeliensis (L.) Desf.), duckweed (Lemna minor), and algae (Microcystis, Vaucheria, and Oocystis) and moss were collected, digested, and analyzed for total Mn, Zn, Ni, Cu, Fe, and Co to determine the extent of bioaccumulation. Results indicate that bioaccumulation of these metals is occurring along the perennial reach of Pinal Creek with bioconcentration factors of 100 to over 10,000 depending upon the plant and the location along the reach. Comparisons with data from Pinto Creek, a nearby perennial creek with significantly lower metal concentrations, indicate that the bioconcentration factors are similar, but the mass of metals present in the aquatic plants at Pinal Creek is significantly higher.