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Glossary
2 3 5
PHANTOM BOTTOM: a false bottom indicated by sonar. Unlike recordings
of echoes from the sea oor, the echoes from this layer are diffuse and
-
ill-dened. When discovered in the early 19405 the source of this sonar
%
disturbance was called the deep scattering layer. Subsequent investiga—
tions have revealed the presence of several layers which vary in depth
?
according to the diurnal migrations of marine animals—see page 207
PHOTOSYNTHESIS: the process by which green plants convert solar energy
;
into a form usable by living things. Essentially the process consists of
the use of light energy to split water into its constituent hydrogen and
oxygen. The hydrogen then takes part in the transformation of carbon
dioxide of the air into the carbon—containing organic materials. In the
sea, the primary task of photosynthesis is carried out by the phytoplankton near and at the surface—see page 27
PHYTOPLANKTON—see plan/an
PLANKTON : the oating, drifting life found in the sea. It is subdivided into
the phytoplankton, plants, and the zooplankton, animals. Ultimately all
life in the sea relies on the ability of the phytoplankton to carry out
photosynthesis and because this involves the use of solar energy the small
microscopic plants such as diatoms are restricted to the sunlit zone of
the surface waters. The zooplankton, however, can be found at most
depths. Frequently members of the zooplankton migrate upwards
during the evening to feed on the phytoplankton retreating deeper
once again With the dawn—see page 28
RAPTURES OF THE DEEP—see nitrogen narcosis
RED CLAY: a ne clay deposit which covers most of the deeper ocean
oor—see page I 14
RED TIDE: bloom of dinoagellates (members of the phytoplankton) in
which the plants become so numerous that the surface water becomes
coloured red. Where the predominant dinoagellates are highly toxic,
for example Gonyaulax, the ensuing red tide may kill many sea birds
and sh—see page 32
—«
REFRACTION OF WATER WAVES:Œhe process by which waves moving into
shallow coastal water come to conform with the contours of the sea
oor. Waves moving in the shallower parts of the sea oor are slowed
down compared with those in the deeper water causing the wave ‘front’
to slew round—see page 13 5
REVERSE OSMOSIS: fresh water is ‘squeezed out’ of sea—water by passing it
under pressure through a membrane which is impermeable to salt and
similar impurities—see page 82
_
SALINE WATER: water with a salt content of 17,000 parts per million or
more.
Glossary
2 3 5
PHANTOM BOTTOM: a false bottom indicated by sonar. Unlike recordings
of echoes from the sea oor, the echoes from this layer are diffuse and
-
ill-dened. When discovered in the early 19405 the source of this sonar
%
disturbance was called the deep scattering layer. Subsequent investiga—
tions have revealed the presence of several layers which vary in depth
?
according to the diurnal migrations of marine animals—see page 207
PHOTOSYNTHESIS: the process by which green plants convert solar energy
;
into a form usable by living things. Essentially the process consists of
the use of light energy to split water into its constituent hydrogen and
oxygen. The hydrogen then takes part in the transformation of carbon
dioxide of the air into the carbon—containing organic materials. In the
sea, the primary task of photosynthesis is carried out by the phytoplankton near and at the surface—see page 27
PHYTOPLANKTON—see plan/an
PLANKTON : the oating, drifting life found in the sea. It is subdivided into
the phytoplankton, plants, and the zooplankton, animals. Ultimately all
life in the sea relies on the ability of the phytoplankton to carry out
photosynthesis and because this involves the use of solar energy the small
microscopic plants such as diatoms are restricted to the sunlit zone of
the surface waters. The zooplankton, however, can be found at most
depths. Frequently members of the zooplankton migrate upwards
during the evening to feed on the phytoplankton retreating deeper
once again With the dawn—see page 28
RAPTURES OF THE DEEP—see nitrogen narcosis
RED CLAY: a ne clay deposit which covers most of the deeper ocean
oor—see page I 14
RED TIDE: bloom of dinoagellates (members of the phytoplankton) in
which the plants become so numerous that the surface water becomes
coloured red. Where the predominant dinoagellates are highly toxic,
for example Gonyaulax, the ensuing red tide may kill many sea birds
and sh—see page 32
—«
REFRACTION OF WATER WAVES:Œhe process by which waves moving into
shallow coastal water come to conform with the contours of the sea
oor. Waves moving in the shallower parts of the sea oor are slowed
down compared with those in the deeper water causing the wave ‘front’
to slew round—see page 13 5
REVERSE OSMOSIS: fresh water is ‘squeezed out’ of sea—water by passing it
under pressure through a membrane which is impermeable to salt and
similar impurities—see page 82
_
SALINE WATER: water with a salt content of 17,000 parts per million or
more.