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“omnivores,” spanning the second,
levels.
third and fourth trophic
Detritus was shown as providing direct linkage only
between the phytoplankton of the pelagic and the algae of
the benthic divisions.
Linkage between the carnivorous forms
of each division waa depicted as through the "omnivore"
classification or via the fifth trophic level,
the transient
carnivores.
In a study of the bottom sediments of Rongelap Atoll
lagoon,
Anikouchine
(1961) concluded that the sediments are
derived almost entirely from organisms living within the
lagoon.
There was no significant loss of sediments from the
lagoon nor exchange of sedimentary material between the lagoon
and oceanic environments.
In such a system,
insoluble atmos-
pheric particles deposited in the lagoon and having sufficient
density to settle through the water would be expected to be
retained in the lagoon.
Finely dispersed,
suspended particles
would be subject to exchange with the oceanic environment along
with the water in which they were suspended.
However, particles
in these smaller size ranges are also subject to surface phenomena such as flocculation and adsorption, and consequently to
gravitational and biological influences tending to retain them
within the lagoon.