SUMMARIZATION

M. G. White and P. B. Dunaway

The annual information conference of the Nevada Applied Ecology Group

(NAEG) held in Las Vegas, Nevada, in February, 1976, provided the environ-

As an ERDA environmental
mental research documents in this report.
has varied disciplines
NAEG
the
group,
studies
integrated research

represented in its meetings.

One of the advantages of holding an annual

meeting of this type is the interface of scientists and technicians
interested in the different aspects of environmental investigations
where a more thorough examination of desert environmental problems is
Some answers, status of ongoing studies, and some new problems
permitted.
were addressed during the session.
The research efforts of the NAEG vegetation investigators resulted in
five reports covering plant uptake of plutonium and americium through
roots, estimation of vegetation plutonium, americium, and uranium radionuclide inventory, stabilization of soils in cleanup efforts by revegetation, a special report on possible cytological effects on shrubs from
low-level radiation at the Nevada Test Site, and report of vegetation

sample results from Area 11 (Plutonium Valley).

An investigation to observe the effects of soil amendments (nitrogen
fertilizer and organic matter, with and without DTPA) on plant uptake of
plutonium and americium was conducted by Romney et al. using soil from
various NAEG NTS intensive study safety-shot sites.
Alfalfa, barley,
and soybean plants were grown in pot culture experiments, in order to

prevent foliage contamination from resuspended soil particulate material
as occurs under field conditions. No alteration of the root uptake of
239°240py was evident with additions of soil amendments such as nitrogen,

fertilizer, and organic matter.
However, when sulfur was added with
DTPA, root uptake significantly increased.
The DTPA amendment apparently
was the agent for this increase, as uptake in soybeans also was significantly increased with the addition of the chelate amendment only.
The
greater uptake of 24am through plant roots in proportion to 239°240py
was demonstrated by the amendment experiments, lending support to the
belief that potential problems from americium in the environment should
be addressed by research investigators as well as those problems from
environmental plutonium.

Romney and co-investigators found that comparisons of soil and vegetation
inventory estimates at NAEG study sites on NTS indicated that plutonium
in the standing vegetation constitutes an insignificant portion (less

than one-thousandth) of the total 239°240py inventory in the study

areas.
Resuspendable materials on vegetation are the probable source of
most of the 239°240py present in vegetation samples from the safety-shot
areas of NTS.
The vegetation in desert environments is important in

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