138
and/or coccolithophores. On the other hand, we have observed a close
correspondence between the ratio ES30 :E 4S0 and mean cell size of
natural populations.
Larger cell sizes in these populations (> 10~)
are associated with ratios of 0.6 to 0.8, whereas small cell sizes «
10~) have ratios of 0.3 or less. The significance of this finding is
that fluorescence signatures appear to be able to provide information
on the mean cell size of the populations which has the advantage
that, with proper optical techniques, these estimates can be made
remotely.
Cell size of phytoplankton, that is surface to volume
ratio relationships and how this is associated with physiology, is
far from being understood, but we do know that the efficiency of
nutrient uptake, respiration and photosynthesis are all apparent
functions of cell size (Malone, 1980).
We believe in this paper,
that we have demonstrated that major spectral features of cellular
fluorescence are associated with change in numbers and species of
phytoplankton and these occur in the regions of transition between
nutrient-rich and nutrient-poor waters.
Such findings tend to
support the hypothesis that a reduction of cell size is a requisite
for phytoplankton survival in oligotrophic regions of the oceans. It
is one of the more important goals in biological oceanography to
delineate in time and space, these regions where marked transitions
in population physiology occur.
In looking at the enormous size of
the ocean, this would appear to be an awesome task if it were not for
the presence of remote sensing techniques.
Ocean color scanner and fluorescence instruments developed by
NASA represent exciting new techniques for the biological oceanographer, and provide a means for assessment of large scale patchiness
of the ocean in a manner only dreamed of by early practitioners in
oceanography. The exciting aspect of the fluorescent LIDAR system is
the ability to characterize the organisms present in the fashion of
their spectral signatures.
At the present time, LIDAR fluorescent
systems are flown by aircraft at low altitudes.
As mentioned, the
instruments induce fluorescence by pulsing strong bursts of blue and
green light into the water column. The present units are capable of
resolving patches of a few meters in size, however, the coverage by
aircraft is limited to the overall flight time of these units.
One
must recognize that the present instruments are merely prototypes and
have their deficiencies, but that they are pioneers of an evolution
that is just beginning.
and/or coccolithophores. On the other hand, we have observed a close
correspondence between the ratio ES30 :E 4S0 and mean cell size of
natural populations.
Larger cell sizes in these populations (> 10~)
are associated with ratios of 0.6 to 0.8, whereas small cell sizes «
10~) have ratios of 0.3 or less. The significance of this finding is
that fluorescence signatures appear to be able to provide information
on the mean cell size of the populations which has the advantage
that, with proper optical techniques, these estimates can be made
remotely.
Cell size of phytoplankton, that is surface to volume
ratio relationships and how this is associated with physiology, is
far from being understood, but we do know that the efficiency of
nutrient uptake, respiration and photosynthesis are all apparent
functions of cell size (Malone, 1980).
We believe in this paper,
that we have demonstrated that major spectral features of cellular
fluorescence are associated with change in numbers and species of
phytoplankton and these occur in the regions of transition between
nutrient-rich and nutrient-poor waters.
Such findings tend to
support the hypothesis that a reduction of cell size is a requisite
for phytoplankton survival in oligotrophic regions of the oceans. It
is one of the more important goals in biological oceanography to
delineate in time and space, these regions where marked transitions
in population physiology occur.
In looking at the enormous size of
the ocean, this would appear to be an awesome task if it were not for
the presence of remote sensing techniques.
Ocean color scanner and fluorescence instruments developed by
NASA represent exciting new techniques for the biological oceanographer, and provide a means for assessment of large scale patchiness
of the ocean in a manner only dreamed of by early practitioners in
oceanography. The exciting aspect of the fluorescent LIDAR system is
the ability to characterize the organisms present in the fashion of
their spectral signatures.
At the present time, LIDAR fluorescent
systems are flown by aircraft at low altitudes.
As mentioned, the
instruments induce fluorescence by pulsing strong bursts of blue and
green light into the water column. The present units are capable of
resolving patches of a few meters in size, however, the coverage by
aircraft is limited to the overall flight time of these units.
One
must recognize that the present instruments are merely prototypes and
have their deficiencies, but that they are pioneers of an evolution
that is just beginning.