Journal of Geophysical Research Oceans,
Год журнала:
2024,
Номер
129(12)
Опубликована: Дек. 1, 2024
Abstract
Understanding
spatiotemporal
variations
in
phytoplankton
biomass
is
crucial
to
the
health
of
marine
ecosystems.
Therefore,
Finite
Volume
Community
Ocean
Model
(FVCOM)‐based
Ecological
(Integrated
Compartment
Model)
was
implemented
assess
nutrient
and
dynamics
Bohai
Sea
from
2010
2019.
From
2013,
dissolved
inorganic
nitrogen
(DIN)
phosphorus
(DIP)
levels
were
higher
(∼0.400
0.030
mg/L,
respectively)
nearshore
areas
compared
other
years.
During
summer
fall,
spatial
distribution
DIN/DIP
ratio
exhibited
a
double‐core
structure.
Higher
values
(>100)
primarily
concentrated
central
region
Liaodong
Bay
south
Central
Basin
near
Yellow
River
Estuary.
Statistical
analyses
numerical
experiments
revealed
that
increasing
DIP
loading
rivers
had
greater
effect
on
Laizhou
Bays
than
DIN
loading.
However,
strongly
influenced
by
both
rivers.
Notably,
increase
resulting
exceeded
17%
Bay.
The
reduction
river
discharge
weakened
circulation
at
mouths,
thereby
partially
retaining
surface
phytoplankton.
This
more
predominant
owing
August
study
provides
valuable
insights
for
management
conservation
Environment International,
Год журнала:
2025,
Номер
196, С. 109317 - 109317
Опубликована: Фев. 1, 2025
Stable
nitrogen
isotopic
composition
(δ15N)
has
proven
to
be
a
valuable
tool
for
identifying
sources
of
nitrates
(NO3-)
in
PM2.5.
However,
the
absence
systematic
study
on
δ15N
values
domestic
NOx
hinders
accurate
identification
NO3-
China.
Here,
we
systematically
determined
and
refined
six
categories
Tianjin
using
an
active
sampling
method.
Moreover,
PM2.5
were
measured
during
pre-heating,
mid-heating
late-heating
periods,
which
are
most
heavily
polluted
Tianjin.
The
results
indicate
that
fingerprints
types
indicative
regional
characteristics
China,
particularly
North
China
Plain.
Bayesian
isotope
mixing
(MixSIAR)
model
demonstrated
coal
combustion,
biomass
burning,
vehicle
exhaust
collectively
contributed
more
than
60
%,
dominating
periods
failure
consider
signatures
local
could
result
overestimation
contribution
from
natural
gas
combustion.
Additionally,
industrial
sources,
uncharacterized
source
previous
studies,
may
directly
fraction
other
being
overestimated
by
10
%.
Notably,
as
number
input
increased,
various
was
becoming
stable,
inter-influence
between
significantly
reduced.
This
fingerprint
effectively
distinguish
NO3-,
thereby
providing
insights
controlling
pollution.
ACS ES&T Air,
Год журнала:
2024,
Номер
1(7), С. 714 - 724
Опубликована: Май 10, 2024
While
the
contribution
of
coal
combustion
to
atmospheric
particulate
matter
is
well-recognized,
its
specific
role
in
winter
haze
remains
insufficiently
explored.
In
this
study,
we
elucidate
quantitative
effect
on
pollution
based
high
temporal
resolution
measurements
trace
metals
PM2.5.
We
identified
arsenic
(As)
and
selenium
(Se)
as
reliable
indicators
combustion,
with
their
enrichment
factors
exceeding
104.
The
significant
increase
As
Se
concentrations
(9.6-fold
7.1-fold
increase)
during
severe
episodes
underscores
enhanced
pollution.
Chemical
mass
closure
results
indicate
that
primary
emissions
from
contribute
15%
PM2.5,
proportion
PM2.5
reaching
42%
57%
non-haze
episodes,
respectively.
Simulations
utilizing
multiphase
chemical
model
(RACM-CAPRAM)
transition
metal-catalyzed
oxidation
responsible
for
68%
secondary
sulfate
formation,
aqueous
phase
surface
catalysis
contributing
59%
9%,
Excluding
combustion-emitted
SO2,
Mn,
Fe
a
49%
reduction
production.
This
research
presents
comprehensive
assessment
impact
northern
China,
offering
vital
insights
formulating
effective
control
strategies
future.
