i.
oTreels te mek bhi,
:
~
2: sas ie
ihe
Mer we.
RENReiR S.
bial
ane aa ee inden EA a AE EA HRN Semen
ry
In the previous chapter it was mentioned that coconuts exhibited
greater beta activity in the present survey than in the previous one,
Interpretation of the nuclide data in coconuts and soils indicates that
this phenomenon is concerned with the apparent capacity of coconuts to
concentrate cesium. Analyses reveal that the activily in coconuts was
contributed almost ererree by Cs7, The argument that this nuclide was
made available to the root system in greater concentration by preferential translocation during this cne year interval is untenable since the
¥
Ee net teeeevel
the only sharp difference was the higher percentage of Cs*?‘ in the one
papaya analyzed in the present study,
oe
concentration of Cs!57 in rela‘ien to other nuclides in the upper surface
when ae
eee a es vient |
eae 6
ef
h
|
_
fare sbi
g
Where comvrariscns vere avaitohte, tha watatiaon hime senna aenlian
in the current surverv wc wl Ae ererb wae bot re poet tad,
+ SR ee ee ey
of the soil is essentially unchanged,
Tay nm eAee de
Further substantiation of the concentrating caf acity of coconuts is
found when the quantity of Cs??? in the coconut is compared with that of
the soil. The soil concentraticn in the area of the root system whichis
situated well below the surface is lower than that of the tep inch of soil,
Yet, as shown in Table A,2, the Cs!37 concentration of coconuts often
exceeded even that which was present in the surface soil,
ener
?
The sunshine units are rccorded in Table 3.2 for the plant, water and
soil samples analyzed. Ti: table includes the d/m Sr” for the sarnples
.and the stanclard error of mzasurement, The standard error was large
in samples with less than 200 d/ra Sr, Towinstruments were used in
counting the renee agai flow proportionai coun.cr with a background
of about 40 c/mand Geigos romuers with bach:
renee ci 23 and 25 c/m,
Although the counting tin:e ./,as routinely 20 min, a sizable statistical
error was involved in rmeasurements of sampies whose rate was only
one to several counts ai.ove background,
to ee gee
To improve the cc unting statistics, a number af samples with low
activity was permitted to stznd until Sr” and Y*’ were in equilibrium,
Both radiations were counted, an appropriate correction was 2zoplied for
self-absorption of Sr®’, an” the 7 contr:‘totion was mathematically
subtracted.
.
Of the plant cane examined, portulec(4
had the highest sunshine
units; values were 0140 ard ee for the is: specimens analyzed,
coconuts the activity «a. prank cnt be eA fake
Wad vb statistically
Significant, whereas the value for husks :areed from 1200 to 4000.
danus keys and pandanus air root values «Jee fell within this range.
In
Pan-
tw cae
Arrowroot leaves, stalks and tubers were sigaificantly lower, ranging
from 86 to 780 sunshine units.
Pn
eenet a Son erypn
antes ae settee ”s
meee
oN
we ey
Peo
ores
i) re ee
.
Pers er
heer om
Ww ape anes
* EEL tty da ee Agi dR tt vee Bs “AT 8)
te
to