INVESTIGATION OF SPATIAL AND TEMPORAL PATTERNS OF CS-137 PARTITIONINGIN ERIOPHORUM-VAGINATUM L. IN RELATION TO ITS NUTRIENT RETRIEVAL AND STORAGE STRATEGY
Dr. Jones et al., INVESTIGATION OF SPATIAL AND TEMPORAL PATTERNS OF CS-137 PARTITIONINGIN ERIOPHORUM-VAGINATUM L. IN RELATION TO ITS NUTRIENT RETRIEVAL AND STORAGE STRATEGY, Journal of environmental radioactivity, 40(3), 1998, pp. 271-288
Relatively high levels of Cs-137 from the Chernobyl accident in indige
nous vegetation in infertile upland habitats in the UK have been partl
y attributed to strategies that permit efficient use of limited nutrie
nt resources. This study investigated temporal and spatial patterns of
Cs-137 allocation in Eriophorum vaginatum L. (hare's-tail cotton-gras
s) in relation to its nutrient retrieval and storage strategy. Plants
were labelled with Cs-137 via root uptake in April 1995 and dissected
components were analysed on six occasions over the following 16 months
. Cs-137 remained relatively mobile in the plants and was recirculated
to new leaves and roots that were initiated after the labelling event
. The retrieval of Cs-137 from maturing leaves was less efficient than
that documented for K and this represented a significant loss process
of Cs-137 from the biomass. A greater loss of Cs-137 occurred through
the roots. Consequently, successively produced leaves contained progr
essively less Cs-137 and an exponential decline in the maximum pool of
Cs-137 (i.e. the maximum accumulation of Cs-137 activity measured in
a leaf) in successively produced leaves was observed. This study provi
des dir ect evidence that strategies that minimise nutrient losses and
permit efficient use of limited nutrient resources in deciduous grami
noids also prolong the presence of Cs-137 in the vegetation of E. vagi
natum. (C) 1998 Elsevier Science Ltd. All rights reserved.