| Monitoring the chromophoric or colored
fraction of dissolved organic matter (CDOM) in natural
waters can be an extremely useful tool in a variety of
marine and freshwater applications. Scientists have
developed numerous methods for measuring or estimating
DOM concentration for a variety of biological, chemical
and physical research and monitoring topics.
Fluorescence detection of CDOM is the easiest and
fastest means of estimating DOM by taking advantage of
CDOM's natural fluorescent property of absorbing UV
light and fluorescing blue light. CDOM measurement is
also of interest to researchers due to its effect on
light in surface waters and as a natural water mass
tracer.
Fluorescence detection is more sensitive, faster and
less expensive than other qualitative measures and
requires no sample handling. Natural water fluorescence
data can be collected without the need to conduct
extractions or other sample preparations. Although
fluorescence data from natural water is a qualitative
measurement, this data has been shown to correlate well
with extracted DOM data. Due to the sensitivity and ease
of use of the fluorometer, data can be collected easily
and quickly in virtually any environment.
Monitoring of CDOM in a continuous, flow-through mode
using the TURNER DESIGN Field
Fluorometer eliminates the problems associated with
sample collection and storage and allows for the
automatic correction of temperature effects. Also,
shipboard on-line monitoring permits the collection of
large data sets along a ship's track.
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可應用範圍包括
/ Applications Include:
- Continuous monitoring of wastewater discharge. CDOM
fluorescence corresponds to total organic carbon (TOC),
which is an indicator of discharge water quality.
- Natural tracer of specific water bodies. CDOM
concentration can indicate the dispersion, transport and
mixing of a water mass.
- Investigations of the magnitude of photosynthetically
active radiation (PAR) and primary production due to its
significant absorption of light in surface waters,
especially in coastal and estuarine areas.
- Ocean color research and the effect of CDOM on satellite
imagery.
- Investigations of DOM cycling and energy budgets.
- Investigations on the effects of photochemical bleaching
of DOM in surface waters.
- The use of CDOM fluorescence data to calculate the
fluorescent quantum yield that is then used to determine
the CDOM absorption coefficient.
參考文獻資料 / References:
- Chen, R.F. and J.L. Bada. 1992. The fluorescence of dissolved organic
matter. Mar. Chem. 37:191-221
- Smart, P.L., B.L. Finlayson, W.D. Rylands,
C.M. Ball. 1976. The relation
of fluorescence to the dissolved organic carbon in
surface waters. Water Res. 10: 805-811
- Wiley, J.D. and
L.P. Atkinson. 1982. Natural fluorescence as a tracer
for distinguishing between Piedmont and Coastal Plain
River water in the nearshore waters of Georgia and North
Carolina. Estuar. Coast. Shelf Science, 14: 29-59
- Vodacek, A., N.V.
Blough, M.D. DeGrandpre, E.T. Peltzer, R.K. Nelson., DOC
in the Middle Atlantic Bight: Terrestrial inputs and
photo oxidation, Limnol Oceanogr. 42(4): 674-686
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