721
Chlorophylls and their Degradation in Nature
Chl a concentrations are greatly variable, ranging from 0.01 to 133.22 μg
L −1 in 38 Chinese lakes. Most of them are mesotrophic (TN = 0.31–2.30 mg
L −1 ; TP = 0.01–0.11 mg L −1 ), five lakes are oligotrophic (TN < 0.31 mg L −1 ;
TP < 0.01 mg L −1 ), and another four lakes are eutrophic (TN > 2.30 mg L −1 ;
TP > 0.11 mg L −1 ) with algal blooms during the summer period (Zhang et al.
2007). The TN:TP ratio ranged from 2:1 to 253:1 for all 38 lakes (Zhang et al.
2007). Chl a concentrations significantly varied (10–145 μg L −1 ) in two Swedish
lakes. In Lake Börringesjön the highest concentration (145 μg L −1 ) has been found
in September, when light attenuation ranged from 4.61 to 7.81 m −1 (Blindow
et al. 2006). Chl a concentrations were low (0.3–1.2 μg L −1 ) in an alpine lake during the ice-cover period, but after ice-break the values increased particularly in
the deep layers. The maximum was observed at 9 m depth (8.5 μg L −1 ), whilst
DOC concentrations in the water column ranged from 10 to 54 μM C (Sommaruga
and Augustin 2006). Chl a concentrations were also very low (0.14–2.85 μg L −1 )
in lake water with low WT (1.2–12.4 °C) and low DOC concentrations (such as
~42 μM C) (Carrillo et al. 2002). In Bohai Sea the vertical distribution of Chl a
and water temperature at depth 0–20 m was approximately 1–2 μg L −1 and
24.7–25.6 °C. The diffuse attenuation coefficient increased with depth, producing
a DCM at around 5–6 m depth (Xiu et al. 2009). High temperature and other factors suggest that this low variation of Chl a (1–2 μg L −1 ) might be caused by high
photoinduced decomposition of Chl a in the surface layer (0–5 m). This result is not
accounted for by DCM, rather it can be considered as SCM or mixed layer depth.
On the other hand, Chl a concentrations in reservoirs are substantially high, ranging from approximately 0.0–919 μg L −1 (Gálvez et al. 1988; Foster et al. 1997; Dasí
et al. 1998; An and Park 2002; Almodovar et al. 2004; Sigareva and Pyrina 2006;
Mineeva et al. 2008; Mineeva and Abramova 2009). The highest Chl a concentrations
were detected in several UK reservoirs, such as <120–919 μg L −1 ; Chl a was then
found at <54.5–239.8 ± 68.2 μg L −1 in several Russia’s reservoirs and <173 μg L −1
in Taechung Reservoir (South Korea) (Table 1). The Chl a concentrations in Gorky
Reservoir varied from 6.3 to 28.0 μg L −1 in both right and left banks, and from 5.9
to 20.6 μg L −1 in riverbed with variation of water temperature (WT) from 19.7 to
21.9 °C. In Cheboksary reservoir, Chl a concentrations were 4.2–72.4 and 6.6 ±
0.7 - 239.8 ± 68.2 μg L −1 , respectively, with variation of WT from 11.0 to 24.0 °C
(Table 1) (Mineeva et al. 2008; Mineeva and Abremova 2009). The peak Chl a levels
in Stanford reservoir exceeded 916 μg L −1 in June and July, but they remained below
25 μg L −1 for the remainder of the sampling period (Foster et al. 1997).
Estuaries
The Chl a concentrations are quite high (0.0–220 μg L −1 ) in estuaries (Table 1)
(Lemaire et al. 2002; Zhu et al. 2009; Stross and Stottlemyer 1965; Pennock 1985;
Abril et al. 2002; Hauxwell et al. 2003; Langston et al. 2003; Gitelson et al. 2007;
He et al. 2010; Craig et al. 2012; Mallin 1994; Gaulke et al. 2010). The highest
Chl a concentrations are <220 μg L −1 in European estuaries; <184 μg L −1 in
North Carolina estuaries; >101 μg L −1 in the Exe Estuary SPA; <80 μg L −1
in Neuse River Estuary; <77.4 μg L −1 in estuaries of Chesapeake Bay; <60 μg
Chlorophylls and their Degradation in Nature
Chl a concentrations are greatly variable, ranging from 0.01 to 133.22 μg
L −1 in 38 Chinese lakes. Most of them are mesotrophic (TN = 0.31–2.30 mg
L −1 ; TP = 0.01–0.11 mg L −1 ), five lakes are oligotrophic (TN < 0.31 mg L −1 ;
TP < 0.01 mg L −1 ), and another four lakes are eutrophic (TN > 2.30 mg L −1 ;
TP > 0.11 mg L −1 ) with algal blooms during the summer period (Zhang et al.
2007). The TN:TP ratio ranged from 2:1 to 253:1 for all 38 lakes (Zhang et al.
2007). Chl a concentrations significantly varied (10–145 μg L −1 ) in two Swedish
lakes. In Lake Börringesjön the highest concentration (145 μg L −1 ) has been found
in September, when light attenuation ranged from 4.61 to 7.81 m −1 (Blindow
et al. 2006). Chl a concentrations were low (0.3–1.2 μg L −1 ) in an alpine lake during the ice-cover period, but after ice-break the values increased particularly in
the deep layers. The maximum was observed at 9 m depth (8.5 μg L −1 ), whilst
DOC concentrations in the water column ranged from 10 to 54 μM C (Sommaruga
and Augustin 2006). Chl a concentrations were also very low (0.14–2.85 μg L −1 )
in lake water with low WT (1.2–12.4 °C) and low DOC concentrations (such as
~42 μM C) (Carrillo et al. 2002). In Bohai Sea the vertical distribution of Chl a
and water temperature at depth 0–20 m was approximately 1–2 μg L −1 and
24.7–25.6 °C. The diffuse attenuation coefficient increased with depth, producing
a DCM at around 5–6 m depth (Xiu et al. 2009). High temperature and other factors suggest that this low variation of Chl a (1–2 μg L −1 ) might be caused by high
photoinduced decomposition of Chl a in the surface layer (0–5 m). This result is not
accounted for by DCM, rather it can be considered as SCM or mixed layer depth.
On the other hand, Chl a concentrations in reservoirs are substantially high, ranging from approximately 0.0–919 μg L −1 (Gálvez et al. 1988; Foster et al. 1997; Dasí
et al. 1998; An and Park 2002; Almodovar et al. 2004; Sigareva and Pyrina 2006;
Mineeva et al. 2008; Mineeva and Abramova 2009). The highest Chl a concentrations
were detected in several UK reservoirs, such as <120–919 μg L −1 ; Chl a was then
found at <54.5–239.8 ± 68.2 μg L −1 in several Russia’s reservoirs and <173 μg L −1
in Taechung Reservoir (South Korea) (Table 1). The Chl a concentrations in Gorky
Reservoir varied from 6.3 to 28.0 μg L −1 in both right and left banks, and from 5.9
to 20.6 μg L −1 in riverbed with variation of water temperature (WT) from 19.7 to
21.9 °C. In Cheboksary reservoir, Chl a concentrations were 4.2–72.4 and 6.6 ±
0.7 - 239.8 ± 68.2 μg L −1 , respectively, with variation of WT from 11.0 to 24.0 °C
(Table 1) (Mineeva et al. 2008; Mineeva and Abremova 2009). The peak Chl a levels
in Stanford reservoir exceeded 916 μg L −1 in June and July, but they remained below
25 μg L −1 for the remainder of the sampling period (Foster et al. 1997).
Estuaries
The Chl a concentrations are quite high (0.0–220 μg L −1 ) in estuaries (Table 1)
(Lemaire et al. 2002; Zhu et al. 2009; Stross and Stottlemyer 1965; Pennock 1985;
Abril et al. 2002; Hauxwell et al. 2003; Langston et al. 2003; Gitelson et al. 2007;
He et al. 2010; Craig et al. 2012; Mallin 1994; Gaulke et al. 2010). The highest
Chl a concentrations are <220 μg L −1 in European estuaries; <184 μg L −1 in
North Carolina estuaries; >101 μg L −1 in the Exe Estuary SPA; <80 μg L −1
in Neuse River Estuary; <77.4 μg L −1 in estuaries of Chesapeake Bay; <60 μg