Uptake and kinetics of /sup 226/Ra, /sup 210/Pb and /sup 210/Po in big sage brush
Root uptake of /sup 226/Pb and /sup 210/Po by mature sage brush was studied using a soil injection method for spiking the soil with minimal root disturbance. The main objective was to measure vegetation concentrations and determine concentration ratios (CR's) due to root uptake as a function of time in mature big sage brush. Concentration ratios obtained in mature vegetation and in steady-state situations may be valuable in assessing the impact of uranium mining and milling. The vegetation was sampled approximately every 3 mo for A 2 y period. Significant levels of activity were detected in the vegetation beginning at the first sampling (81 d after soil injection for /sup 226/Ra, 28 d for /sup 210/Pb and /sup 210/Po). There was an exponential decrease in concentration to an apparent steady state value. Mean values (geometric) of the data pooled over the second year period indicated that steady-state Cr's for /sup 226/Ra, /sup 210/Pb and /sup 210/Po, as determined in mature sage brush, were 0.04, 0.009, and 0.08, respectively. Investigations were also carried out to verify the suitability of soil injection for uptake studies and to evaluate the time dependence of /sup 226/Ra leaching from sage brush leaves. The soil injection method was determined to produce, on the average, uptake equivalent to that produce by a uniform soil distribution, however, the variety of uptake for plants growing in injected soil was higher than for plants growing in uniformly contaminated soil. A three compartment mathematical model was formulated to help understand mechanisms of plant uptake and to predict, if possible, the concentration of /sup 226/Ra, /sup 210/Po in vegetation as a function of time after soil spiking.
- Research Organization:
- Colorado State Univ., Fort Collins (USA)
- OSTI ID:
- 7169915
- Resource Relation:
- Other Information: Thesis (Ph. D.)
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
LEAD 210
ROOT ABSORPTION
POLONIUM 210
RADIUM 226
SHRUBS
RADIONUCLIDE KINETICS
CONCENTRATION RATIO
MATHEMATICAL MODELS
SOILS
ABSORPTION
ALKALINE EARTH ISOTOPES
ALPHA DECAY RADIOISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
DAYS LIVING RADIOISOTOPES
EVEN-EVEN NUCLEI
HEAVY NUCLEI
ISOTOPES
LEAD ISOTOPES
NUCLEI
PLANTS
POLONIUM ISOTOPES
RADIOISOTOPES
RADIUM ISOTOPES
UPTAKE
YEARS LIVING RADIOISOTOPES
560162* - Radionuclide Effects
Kinetics
& Toxicology- Animals
Plants
Microorganisms
& Cells