To
RESULTS
ATOLL GEOGRAPHY AND NUMBER OF SAMPLES COLLECTED BY ISLAND AND SAMPLE TYPE
The islands at Bikini Atoll that were sampled as part of the NMIRS are
listed in Table 2 by name and code number.
Included in Table 2 are the size
of the island and the numbers of samples collected.
The locations of the
major islands within the atoll are shown in Fig. 2.
Bikini and Eneu Islands make up “about 50% of the atoll land area; over
70% of the land area is accounted for if Nam and Enidrik Istands
included.
are
Although Enidrik is the third largest island at the atoll, it has
not been a residence island, perhaps because it is subject to severe storm
conditions.
Beach rubble is found half way across the istand, and the native
vegetation is stunted, nutrient deficient, and unhealthy looking.
Most of the
other islands are rather small and/or narrow and are also subject to being
awash with salt water during high-wind and high-tide situations.
During the 1978 survey, 134 soil profiles were collected at islands other
than Bikini and Eneu; these profiles consist of a total of 792 soil samples.
Generally, more samples were taken at larger islands than at smaller islands.
Over the years, we have collected a total
of 456 soil profiles at Bikini. and
Eneu Islands; these profiles comprise 2538 soil samples.
Only two islands other than Bikini and Eneu have edible food crops and in
both cases (Aerokojlol and Jelete) coconut is the available food.
Extensive
sampling of vegetation has been carried out at Bikini and Eneu Islands.
COMPOSITION OF ATOLL SOIL
The composition of coral soil for two soil profiles from Bikini Island
and one soil profile from Eneu Island is listed in Table 3.
The coral soil is
comprised mostly of CaCO3, with some MgCO3, and essentially no clay.
is high, ranging from 7.7 to 9.0.
matter
(as much
as
14%),
although
The pH
The surface horizons are high in organic
the organic matter in the soils drops
markedly with depth in the soil column.
As a result, most of the natura!
nutrient and water-retention capacity of the soil is confined to the top 25 to
40 cm of the soil column.
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