184
RECOVERY OF THE LAND PLANTS AT ENIWETOK ATOLL
Island by the Division of Biology and Medicine
of the United States Atomic Energy Com-
plants also were observed. Before the Nec
detonation the plants were staked, label
measured and photographed. After the deto
tion, and at approximately monthly inter.
thereafter, observations and measurements w
made of the plants and photographs were tak
Scaevola sericea Vahl, a woody shrub, was cho:
as the principal plant for study because of
widespread occurrence on the islands of 1
Central Pacific Ocean. The other plants studi
in detail were: Messerschmidia argentea, Guetta
Speciosa and- Cocos nucifera, trees; Lepturus repe
a grass; Boerhaavia tetrandra and Triumfe
procumbens, prostrate vines; and Portulaca olerac
a fleshy herb. The locations of these plants .
the island are shownin Fig. 2.
Gamma survey-meter readings also were tak:
to determine the gamma dose to which t!
plants were subjected.
mission, and logistic support to carry out the
sampling programme was furnished by Joint
Task Force Seven of Operation Castle.
The study of the land plants was a part of the
over-all programmeof the Laboratory of Radiation Biology. In this report only the results of
this portion of the programme are presented.
The results of the investigations on the following
organisms already have been reported: reef
fish,29) land crabs,“ invertebrates‘, and
algae.0%
The objective of the land plant programme
was to determine the length of time required
for a plant damaged by a nuclear detonation
to resume its normal functions of growth and
reproduction while being subjected to chronic
radiation.
The main site of study was Belle Island
(Bogombogo}, 2:7 miles W-SW of the detonation (Fig. |). This area was estimated to be far
enough removed from ground zero that the
plants would not be uprooted by physical forces
we
RESULTS
The gamma survey-meter readings taken .
Belle Island during the period of investigatic
are given in Fig. 3, which includesthe theoretic.
gamma dose rate according to MILLER an
yet would be in an area of sufficient radio-
Loes.“® The accumulated total dose from or.
activity for the proposed study.
minute after the detonation to the end of 20
days was calculated to be approximately 400 :
METHODS
Representative plants of the eight most
common species growing in the area were
studied in detail; however, numerous other
nied ecicitoe battihe oe?
Secward
Scale;lin:|SOyd.
Before the Nectar detonation, the plants o
Belle Island were generally green and health.
reef fiat
Lagoon
Ceca
Fic. 2. Diagram of Belle Island, Eniwetok Atoll, showing the location of the land plant
stations and the collecting areas.
Area A
1216 Guettarda speciosa
1408 Messerschmidia argentea
1410 Lepturus repens
ETTT
1207
1208
1211
1412
Area C
Boerhaavia tetrandra
Triumfetta procumbens
Portulaca oleracea
Cocos nucifera
Area D
1319 Scaevola sp.