SREL Reprint #2581

Ecological half-life of 137Cs in plants associated with a contaminated stream

John D. Peles1, Michael H. Smith2, and I. Lehr Brisbin Jr.2

1207 Ostermayer Laboratory, Pennsylvania State University - McKeesport, 400 University Drive, McKeesport, PA 15132, USA
2Savannah River Ecology Laboratory, Drawer E, Aiken, SC 29802, USA

Abstract: Ecological half-life (Te) is a useful measure for studying the long-term decline of contaminants, such as radionuclides, in natural systems. The current investigation determined levels of radiocesium (137Cs) in two aquatic (Polygonum punctatum, Sagittaria latifolia) and three terrestrial (Alnus seerrulata, Myrica cerifera, Salix nigra) plant species from a contaminanted stream and floodplian on the U.S. Department of Energy's Savannah River Site. Current 137Cs levels in plants were used in conjunction with historical data to determine Te of 137Cs in each species. Median concentrations of 137Cs were highest in S. latifolia (0.84 Bq g-1) and lowest in M. cerifera (0.10 Bq g-1). Te's ranged from 4.85 yr in M. cerifera to 8.35 yr in S. nigra, both terrestrial species. Te's for all aquatic (6.30 yr) and all terrestrial (5.87) species combined were very similar. The Te's of the two aquatic primary producers (P. punctatum and S. latifolia) in the Steel Creek ecosystem were somewhat longer than Te values previously reported for some consumers from this ecosystem.

Keywords: Ecological half-life; Long-term decline; Radiocesium; Vegetation; Primary producers

SREL Reprint #2581

Peles, J. D., M. H. Smith, and I. L. Brisbin, Jr. 2002. Ecological half-life of 137Cs in plants associated with a contaminated stream. Journal of Environmental Radioactivity 59:169-178.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).