quantitative determinations from a few profiles.
Gamma-ray
spectra of equal amounts of soil from different depths were
compared directly to arrive at (1) a qualitative evaluation
of the vertical distribution of the radionuclides and
(2)
a
semiquantitative estimate of relative amounts of radionuclides
at different depths.
Gamma-ray spectra were made with a system
which included a 3-inch by 3-inch solid,thallium-activated,
sodium iodide crystal and a 256-channel analyzer.
In addition,
selected samples were taken for analyses of the pure betaemitter, sr??,
RESULTS AND DISCUSSION
Vertical distribution in relation to soil type is made by
comparing young and old soils.
young soil,
Examples are Kabelle Sand, a
(Fig. 2) and Gogan Gravelly Sandy Loam (Fig. 3) and
Lomuilal Sand
(Fig. 4),
old soils.
Their characteristics are
given in Tables I and III.
The young soil has little organic material except that in
an algal surface crust about 1 cm thick.
Hermit crabs, Coeno-
bita perlatus, at the base of a few shrubs, the borrowing ghost
crab,
Ocypode ceratopthalmia, and ants are the main animals
present,
Litter accumulation is found only at the bases of
the scattered shrubs and is a minor part of this soil system.