Ms. Kelly et Je. Pinder, FOLIAR UPTAKE OF CS-137 FROM THE WATER COLUMN BY AQUATIC MACROPHYTES, Journal of environmental radioactivity, 30(3), 1996, pp. 271-280
A transplant experiment was performed to determine the relative import
ances of root uptake from the sediments and foliar uptake fr om the wa
ter column in determining the accumulation of Cs-137 by aquatic macrop
hytes. Uncontaminated individuals of three species, Brasenia schreberi
, Nymphaea odorata and Nymphoides cordata, were transplanted into pots
containing either contaminated sediments (i.e. 1.2 Bq Cs-137 g(-1) dr
y mass) of uncontaminated sediments (i.e. <0.1 Bq g(-1) dry mass) and
immersed in Pond B, a former reactor cooling pond where Cs-137 concent
rations in surface waters range from 0.4 to 0.8 Bq liter(-1). The plan
ts in uncontaminated sediments rapidly accumulated Cs-137 from the wat
er column and after 35 days of immersion had Cs-137 concentrations in
leaves that were: (1) nor statistically significantly different from t
hose for plants in contaminated sediments, and (2) similar to those fo
r the same species growing naturally in Pond B. The similarity in Cs-1
37 concentrations between naturally-occurring plants and those in pots
with uncontaminated sediments suggests that foliar uptake from the wa
ter column is the principal mode of Cs accumulation by these species i
n Pond B.