Frontiers in Marine Science,
Journal Year:
2022,
Volume and Issue:
9
Published: April 28, 2022
Nutrients
play
an
important
role
as
biogenic
elements
in
modulating
marine
productivity,
and
water
mixing
usually
facilitates
the
transportation
of
nutrients
coastal
ocean.
In
this
study,
distributions
naturally
occurring
radioisotopes
226
Ra
228
surface
column
northern
South
China
Sea
(NSCS)
have
been
investigated
to
estimate
oceanic
nutrient
supplies.
We
identified
three
masses
Warm
Current
(SCSWC),
Branch
Kuroshio
(SCSBK),
shelf
summer
June
2015,
but
only
SCSWC
SCSBK
were
observed
spring
March
2017.
The
fraction
was
estimated
be
average
0.25
±
0.16,
which
lower
than
that
0.57
0.32
our
study
area.
horizontal
from
Pearl
River
plume
revealed
eddy
diffusion
(1.2
0.79)
×
10
5
cm
2
/s
advection
velocity
ω
0.16
cm/s
slope
region.
column,
best-fit
exponential
curve
gradient
led
a
vertical
coefficient
0.43
0.33
went
down
subsurface
upper
1,000
m,
upward
18
9.9
near-bottom.
Combining
distributions,
carried
(5.6
4.9)
mmol
N/m
/d,
2.2
2.0
P/m
(4.1
3.9)
Si/m
/d
very
layer,
suggesting
plays
significant
sources
NSCS
during
2015.
supplied
2.7
1.6
0.18
0.11
15
8.4
appeared
more
atmospheric
deposition
rivaled
submarine
groundwater
discharge.
Journal of Geophysical Research Oceans,
Journal Year:
2024,
Volume and Issue:
129(7)
Published: June 27, 2024
Abstract
Previous
studies
have
primarily
focused
on
the
impact
of
human
activities
coastal
dissolved
organic
matter
(DOM)
cycles,
while
neglecting
role
dynamic
processes.
This
limits
our
comprehensive
understanding
processes
DOM,
particularly
in
waters
affected
by
multiple
In
this
study,
dynamics
DOM
northwestern
South
China
Sea
(SCS)
were
investigated
using
DOM‐related
parameters
and
a
three
end‐member
mixing
model,
which
accounted
for
effects
currents
upwelling
during
spring,
summer,
winter
seasons.
Our
results
demonstrated
that
net
addition
was
predominantly
observed
nearshore
all
seasons,
owing
to
strong
induced
phytoplankton
production
particle
desorption.
However,
weaker
spring
winter,
removal
decomposition
western
offshore
area.
observation
can
be
attributed
abundance
microorganisms
increased
vertical
water
winter.
Conversely,
stronger
provided
more
bio‐refractory
limiting
its
decomposition,
whereas
stimulated
productivity
desorption,
resulting
period.
eastern
area,
primary
mechanism
eliminating
weak
or
absent
upwelling.
study
revealed
is
widespread
regions
SCS
facilitate
DOM.
Frontiers in Marine Science,
Journal Year:
2022,
Volume and Issue:
9
Published: April 28, 2022
Nutrients
play
an
important
role
as
biogenic
elements
in
modulating
marine
productivity,
and
water
mixing
usually
facilitates
the
transportation
of
nutrients
coastal
ocean.
In
this
study,
distributions
naturally
occurring
radioisotopes
226
Ra
228
surface
column
northern
South
China
Sea
(NSCS)
have
been
investigated
to
estimate
oceanic
nutrient
supplies.
We
identified
three
masses
Warm
Current
(SCSWC),
Branch
Kuroshio
(SCSBK),
shelf
summer
June
2015,
but
only
SCSWC
SCSBK
were
observed
spring
March
2017.
The
fraction
was
estimated
be
average
0.25
±
0.16,
which
lower
than
that
0.57
0.32
our
study
area.
horizontal
from
Pearl
River
plume
revealed
eddy
diffusion
(1.2
0.79)
×
10
5
cm
2
/s
advection
velocity
ω
0.16
cm/s
slope
region.
column,
best-fit
exponential
curve
gradient
led
a
vertical
coefficient
0.43
0.33
went
down
subsurface
upper
1,000
m,
upward
18
9.9
near-bottom.
Combining
distributions,
carried
(5.6
4.9)
mmol
N/m
/d,
2.2
2.0
P/m
(4.1
3.9)
Si/m
/d
very
layer,
suggesting
plays
significant
sources
NSCS
during
2015.
supplied
2.7
1.6
0.18
0.11
15
8.4
appeared
more
atmospheric
deposition
rivaled
submarine
groundwater
discharge.
