Environmental Engineering Reference
In-Depth Information
in freshwater (Mostofa et al.
2005a
; Mostofa et al.
2010
; Westerhoff et al.
2001
;
Baker
2002
; Baker et al.
2004
); (iii) To monitor the microbial decomposition of
DOM (Hayase et al.
1988
; Moran et al.
2000
; Nieto-Cid et al.
2006
); and (iv) to
monitor the molecular weight distribution of DOM (Fu et al.
2006
; Yoshioka et
al.
2007
; Wu et al.
2003a
; Belzile and Guo
2006
; Huguet et al.
2010
) and changes
in its composition at the watershed level (Mostofa et al.
2005b
; Chen et al.
2003
;
Baker et al.
2004
), or from coastal waters to open oceans (Yamashita and Tanoue
2003b
).
Finally, the EEMS could be useful in technology development or fundamental
research, in the field or at the level of molecular science (Mostofa et al.
2009a
).
The EEMS has already been applied: (i) In biomedicine or biotechnology to con-
trol fermentation in bioreactors (Li and Humphrey
1990
) and to detect bacterial
biofilms (Angell et al.
1993
); (ii) In the detection of natural substances in water
such as peroxides (hydrogen peroxide and organic peroxides), allochthonous
fulvic and humic acids, proteins, amino acids and so on (Yamashita and Tanoue
2003a
,
2003b
; Nagao et al.
2003
; Fujiwara et al.
1993
; Wu et al.
2003a
,
2003b
);
(iii) In the examination of the biological activity in cultures of marine bacteria,
algae and coral extracts (Determann et al.
1998
; Matthews et al.
1996
; Cammack
et al.
2004
; Elliott et al.
2006
); (iv) In the identification of the chemical proper-
ties at the molecular level, which arise by interaction between DOM and trace ele-
ments (Senesi
1990a
,
1990b
; Wu et al.
2004a
,
2004b
,
2007
; Yamashita and Jaffé
2008
), and (v) in the study of the interaction of DNA with fluorescent substances,
e.g. in the framework of DNA-protein interaction (Taylor et al.
2000
).
6.1 Are FDOM Studies Superior to CDOM?
The absorption spectra of chromophoric or colored dissolved organic mat-
ter (CDOM) usually do not show any specific identifiable peak for freshwater
and marine CDOM. CDOM absorption and fluorescence (fulvic or humic acid-
like) are significantly correlated with each other in a variety of waters (Ferrari et
al.
1996a
; del Vecchio and Blough
2004
,
2002
; Nieke et al.
1997
; Vodacek et al.
1995
; Ferrari et al.
1996b
; Ferrari
2000
; Green and Blough
1994
; Seritti et al.
1998
; Blough and del Vecchio
2002
; Stabenau and Zika
2004
). The absorb-
ance of CDOM is useful for one to know the contents of the materials present
as well as to identify changes in absorbance of total DOM due to physical, pho-
toinduced and biological processes (del Vecchio and Blough
2004
,
2002
; Coble
2007
; Vodacek et al.
1997
; Vähätalo and Wetzel
2004
; Vähätalo et al.
2000
). The
slope of the absorption spectrum is widely used in remote sensing in coastal and
marine environments (Vodacek et al.
1995
; Hoge et al.
1995
). It has been reported
that there are differences in levels and optical properties between freshwater and
marine CDOM. Extreme enrichment in CDOM is usually observed in freshwater
environments (Del Vecchio and Blough
2004
,
2002
; Conmy et al.
2004
; Vähätalo
and Wetzel
2004
; Kowalczuk et al.
2003
). Freshwater CDOM absorbs radiation at
