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Doppler effect
number of species among a fixed number of individuals or per unit surface)
is incorporated, the best way to express diversity is by the Shannon and Weaver
index: H'= -Ipilog2Pi' where Pi = n;lN and n i the number species i.
diversity index --7diversity.
diverticulum (pi. diverticula) blind-ending tubular or sac-like protuberance
from a cavity.
DMS --7dimethyl sulfide.
DNA (deoxyribonucleic acid) a polymer of nucleotides connected via a phosphatede-oxyribose sugar backbone; it is the genetic material of the living
cell.
DOC dissolved organic carbon, --7particulate organic carbon, --7carbon, organic.
doldrums climatic zone in the tropics, --7c1imate.
dolomite --7carbonate, mineral.
dolphins --7mammals, marine, but also confusingly used for a family of oceanic fish
(Coryphaenidae ).
DOM dissolved organic matter, --7particulate organic matter.
domestic waste --7waste.
dominance --7diversity.
Doppler effect the apparent change in frequency of a wave signal from a source
that is moving relative to the detector, theoretically described in 1842 by
C. Doppler (1803-1853). In measuring instruments a moving source is not
directly used, but rather the backscattered signals from a source that is
mounted near the detector. In oceanographic instrumentation this effect is
used with acoustic signals, and with electromagnetic signals (light and
radar). Acoustic applications are the Doppler Sonar to determine the speed
of a ship with respect to the bottom, and the acoustic Doppler current
meter. This latter has the advantage that the flow is not affected by the
instrument, as is the case with propellor-type current meters. In the laser
Doppler turbulence meter, laser light is used to measure velocity fluctuations in a volume of less than a cubic millimeter. Radar signals, backscattered from surface waves, are used to measure surface currents by this principle.
Doppler effect
number of species among a fixed number of individuals or per unit surface)
is incorporated, the best way to express diversity is by the Shannon and Weaver
index: H'= -Ipilog2Pi' where Pi = n;lN and n i the number species i.
diversity index --7diversity.
diverticulum (pi. diverticula) blind-ending tubular or sac-like protuberance
from a cavity.
DMS --7dimethyl sulfide.
DNA (deoxyribonucleic acid) a polymer of nucleotides connected via a phosphatede-oxyribose sugar backbone; it is the genetic material of the living
cell.
DOC dissolved organic carbon, --7particulate organic carbon, --7carbon, organic.
doldrums climatic zone in the tropics, --7c1imate.
dolomite --7carbonate, mineral.
dolphins --7mammals, marine, but also confusingly used for a family of oceanic fish
(Coryphaenidae ).
DOM dissolved organic matter, --7particulate organic matter.
domestic waste --7waste.
dominance --7diversity.
Doppler effect the apparent change in frequency of a wave signal from a source
that is moving relative to the detector, theoretically described in 1842 by
C. Doppler (1803-1853). In measuring instruments a moving source is not
directly used, but rather the backscattered signals from a source that is
mounted near the detector. In oceanographic instrumentation this effect is
used with acoustic signals, and with electromagnetic signals (light and
radar). Acoustic applications are the Doppler Sonar to determine the speed
of a ship with respect to the bottom, and the acoustic Doppler current
meter. This latter has the advantage that the flow is not affected by the
instrument, as is the case with propellor-type current meters. In the laser
Doppler turbulence meter, laser light is used to measure velocity fluctuations in a volume of less than a cubic millimeter. Radar signals, backscattered from surface waves, are used to measure surface currents by this principle.