Environmental Engineering Reference
In-Depth Information
chlorination or in conventional and advanced wastewater treatment plants (Scully
et al.
1988
; Jensen and Helz
1998
; Jameel and Helz
1999
; Mitch et al.
2003
).
4 Contribution of Organic Substances to DOM
in Natural Water
The contributions of major organic substances in streams and rivers to the total
DOM pool are 20-85 % of humic substances, of which 15-80 % fulvic acid and
5-29 % humic acid (the ratio of fulvic acid to humic acid is 9:1 for lower stream
DOC and it decreases to 4:1 or less for higher stream DOC), 10-30 % of carbo-
hydrates, 2-48 % of dissolved amino acids, organic acids or hydrophilic acids
(9-25 %), autochthonous fulvic acids of phytoplankton or algal origin (or marine
humic-like: see
Sect. 3.2
and also FDOM chapter for detailed description), organic
acids, organic peroxides (ROOHs), sterols; organic contaminants of anthropo-
genic origin and so on (Mostofa et al.
2009a
; Malcolm
1985
,
1990
; Bertilsson
et al.
1999
; Lu et al.
2007
; Wetzel and Manny
1972
; Meybeck
1982
; Meyer and
Tate
1983
; Ittekkot et al.
1985
; Thurman
1985b
; Meyer
1986
; Tipping et al.
1988
;
Lewis and Saunders
1989
; Peuravuori
1992
; Hedges et al.
1994
; Eatherall
1996
;
Volk et al.
1997
; Kusel and Drake
1999
; Peuravuori and Pihlaja
1999
; Alberts and
Takács
1999
; Ma et al.
2001
; Raymond and Bauer
2001a
; van Hees et al.
2002
;
Nagai et al.
2005
; Mostofa
2005
; Guéguen et al.
2006
). Hydrophilic acids gener-
ally include amino acids, proteins, carbohydrates and free sugars. The contribu-
tion of humic substances (hydrophobic acids) in groundwater is approximately
12-98 % (1-80 % of fulvic acid and 2-97 % of humic acid), and the contribu-
tion of hydrophilic fractions is 1-82 % (Buckau et al.
2000
; Bertilsson et al.
1999
;
Peuravuori and Pihlaja
1999
; Leenheer et al.
1974
; Thurman
1985c
; Ford and
Naiman
1989
; Schiff et al.
1990
; Wassenaar et al.
1990
; Malcolm
1991
; Gr
n et al.
1996
; Christensen et al.
1998
; McIntyre et al.
2005
; Mladenov et al.
2008
). These
studies observe high variation in the contribution of humic substances from stream
(source) to the end of river mouths. The main reasons are the mixing up of vari-
ous sources of water in the downstream locations as well as the photoinduced and
microbial changes during transportation.
In lakes the contributions of humic substances (fulvic and humic acids) account
for 14-90 % of total DOM (14-70 % of fulvic acid and 0-22 % of humic acid);
the DOM pool is also made up of ~12-60 % of autochthonous fulvic acids (see
FDOM chapter for detailed description) of algal or phytoplankton origin; of car-
bohydrates for 1-65 %; of amino acids, proteins and organic acids that together
account for 10-33 % of total DOM; of organic acids (2.5-7.5 %, but 0-11 %
in pore water); sterols; algal toxins, organic contaminants of anthropogenic
origin and so on (Mostofa et al.
2009a
,
b
; Parlanti et al.
2000
; Xiao and Wu
2011
; Wilkinson et al.
1997
; McKnight et al.
1991
,
1994
,
1997
; Xiao et al.
2009
,
2011
; Thurman
1985b
; Peuravuori
1992
; Peuravuori and Pihlaja
1999
; Ma et al.
2001
; Nagai et al.
2005
; Schiff et al.
1990
; Steinberg and Muenster
1985
; Hama
ǿ