Environmental Engineering Reference
In-Depth Information
high DOM contents that provide nutrients and simultaneously attenuate high solar
radiation. Model results reveal that the progressive release of dissolved organic
nitrogen (DON) in the ocean's upper layer during summer increases primary pro-
duction by 30-300 %. This leads in turn to an enhancement of the dissolved organic
carbon (DOC) production mainly from phytoplankton exudation in the upper layer
and to solubilization of POM in the deeper layers (Druon et al.
2010
).
Fig. 4
Variations of biological characteristics in surface seawater from the coasts to pelagic
waters. Phytoplankton biomass (Chl
a
, in
μ
g L
−
1
) and piconanoplankton fractions (<20
μ
m,
in %); the fitted lines are power functions (
Y
=
A
x
B
, R
2
=
0.47 for Chl
a
and 0.32 for piconano-
fractions) (
a
); (
b
) and (
c
) Photosynthetic carbon fixation rates per volume of seawater (in
μ
g C
L
−
1
] (
c
) under PAR (P), PAR
+
UV-A
(PA) or PAR
+
UV-A
+
B (PAB); the fitted lines are the power functions (R
2
=
0.38-0.63);
Photosynthetic inhibition (in %) induced by UV-A or UV-B (
d
) where the solid line indicates
the significant relationship between the UV-A-induced inhibition and the distance off the coast
(R
2
=
0.31, P < 0.01, n
=
32). Vertical bars present the standard deviations (n
=
3).
Data source
Li et al. (
2011
)
−
1
h
−
1
) (
b
) or based on Chl
a
[in
μ
g C (
μ
g Chl
a
)
−
1
h
