./& POTASSIUM IN DRIED MILK PROpUOTS
SAMPLING STATIONS IN THE WNoRTHY 1959-JUNE 1960, GROUPED aCcCORDING
VEGETATION ZONES
‘o.. of
mples
Prectpitaavg. ™7Cs tion total
pe/g K
inches
65
a9
67
67
?
ave. 90
65
51
avg. 61
20
29
avg. 54
avg. 29
76
58
31
78
70
73
73
92
42
43
22
43
49
34
avg. 37
55
°% of ppt
in winter
months
52
47
lo
a
37
—_
12
—
9
18
55
49
9
_
avg. 12
28
—
tations showed the coniferous
iving an average of 61 in. from
11960. This was compared with
12 in. from grassland and sageIt is realized that precipitation
ms probably do not represent
of the precipitation over the
1evertheless, natural vegetation
iveness of precipitation and fhe
be used to delimit long-term
long been recognized by plant
al precipitation in the northnot sufficient to differentiate
zone climates®. The seasonal
on in the sage-brush zone is
iths, while that of the grassland
pring and’ summer (Table 1).
1 greatly influence the amounts
1 foliar surfaces. In temperate
seasonal agricultural yield foliar
ts the amounts largely accumu-
relation to the cesium-137 content of milk an analysis of
variance was performed which included seasonal effects.
The hypothesis of no zonal effect was rejected at the 1 per
cent level of significance. Additional inferences were
obtained by subsequent tests for judging contrasts’. All
three contrasts between means were significant at the
I per cent level. The computed values: $,12 pe.
cxesium-137/g potassium; ),>-32 cesium-137 pe./g potassium; where +, is the difference between the meansof the
grassland zone and the sage-brush zone and , is the
difference between the means of the forest and grassland
zones.
This work was performed under contract No. AT(45—1)-1350 between the U.S. Atomic Energy Commission
and the General Electric Co.
W. H. Rickarp
A. D. Wiccrns
Biology Laboratory,
Applied Mathematics Operation.
‘
Hanford Laboratories,
General Electric Co.,
J. K. FrRemMstTap
Richland, Washington.
1 Kulp, J. L., Sehulert, A. R., Hodges, E. J., Anderson, E. C., and Langhan.>
W. H., Setence, 183, 1768 (1961).
1 Health and Safety Lab. Strontium Program, Quart. Summary Rep., HASL-77
88, 95 (1960).
‘Shantz, H. L., and Zon, R., in Atlas of American Agriculture, Pt. 1, Sect.
&, 29 (U.S. Dept. Agric., Washington, D.C., 1924).
‘Langham, W. H., and Anderson, E. C., Health Phys,,2, 30 (1959).
* Low, K., and Fdvarson, K,, Nature, 187, 736 (1960).
“Daubenmire, R., Plants and Environment (Wiley and Sons, Inc., New
York, 1947).
Sen) The Analysis of Varianee (Wiley and Sons, Inc., New York
hotosynthetic period. Forages
brush zone seldom experience
growth water is supplied by
d zone growth of forage crops
oincide to yield higher czsium1e non-synchrony ofbiological
nd lower cesium-137 values in
am-137 content of dried milk
: moist forest zone appears
itation in this zone in contrast
rush zones. The lower average
iducts produced in the sageissland zone appear as a result
nological and meteorological
agement practices.
effect of vegetation zones in
Printed im Great Britain by Fisher, Knight & Co., Ltd., $1. “Albans.