Limnology and Oceanography,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 18, 2025
Abstract
The
benthic
flux
of
nutrients
underpins
marine
food
webs,
influences
conditions
for
life
in
the
oceans,
and
contributes
to
climatic
feedback.
Estimates
these
fluxes'
contributions
macro‐
micronutrient
cycles
are,
however,
highly
variable,
generating
significant
uncertainty
biogeochemical
models.
Traditional
methodologies
have
potentially
limitations,
geochemically
framed
studies,
there
is
a
notable
omission
from
macrofaunal
activity.
224
Ra/
228
Th
disequilibrium
cutting‐edge
geochemical
technique
quantifying
flux;
its
capacity
incorporate
influence
fauna
has
not
been
assessed.
Here
we
present
first
results
using
examine
four
macrobenthic
infaunal
invertebrate
species
on
macronutrients
(,
,
)
between
sediment
water
column.
Overall,
estimates
were
up
15
times
greater
than
those
derived
commonly
used
methods,
both
Ra
nutrient
fluxes
differed
presence
different
macrofauna.
greatest
efflux
influx
occurred
burrowing
actinarian
Edwardsia
claparedii
patterns
suggested
mechanisms
species.
Notable
variability
enhancement
was
also
individuals
same
species,
highlighting
complex
relationship
biodiversity
ecosystem
functioning.
We
conclude
that
powerful
tool
interdisciplinary
ecological
if
applied
widely
enough
may
more
holistically
represent
dynamics
natural
environment
standard
approaches.
Geochimica et Cosmochimica Acta,
Journal Year:
2023,
Volume and Issue:
364, P. 79 - 88
Published: Nov. 23, 2023
The
quantification
of
anaerobic
oxidation
organic
matter
in
the
global
seabed
is
to
a
large
extent
based
on
transport-reaction
modeling
pore
water
ions
involved
mineralization
processes.
As
predominant
these
processes,
sulfate
reduction
can
be
modeled
from
depth
distribution
and
other
relevant
solutes.
An
active
organoclastic
typically
characterized
by
profiles
with
concave-down
shape.
We
use
here
comprehensive
database
show
that
half
all
competent
have
an
opposite,
concave-up
shape,
which
may
appear
inconsistent
this
concept.
also
there
strong
discrepancy
between
obtained
gravity
coring
IODP
coring,
generally
much
higher
flux
shallower
penetration
cores
(the
term
covers
international
ocean
drilling
programs,
DSDP,
ODP
IODP).
correlated
selectivity
for
sites
published
studies,
focused
towards
margins
continental
shelf
high
surface
productivity
sedimentation
rate.
In
contrast,
more
frequently
done
low
regions
largely
absent
shelf.
result,
estimates
biased
selection
only
core
data
modeling.
Furthermore,
shows
net
rates
reduction,
while
35S-radiotracer
experiments
gross
process.
Estimates
measurements
suggest
dissimilatory
oxidizes
77
Tmol
yr-1
carbon
globally,
3-
4-fold
than
recent
data.
potential
biases
marine
sediments
are
discussed.
Deep Sea Research Part I Oceanographic Research Papers,
Journal Year:
2024,
Volume and Issue:
204, P. 104235 - 104235
Published: Jan. 15, 2024
Kaikōura
Canyon,
offshore
Aotearoa/New
Zealand,
is
a
hotspot
for
deep-sea
benthic
biology
with
globally
high
faunal
abundance.
The
Mw7.8
earthquake
in
2016
triggered
severe
disturbance
that
reshaped
the
canyon,
evacuating
an
estimated
850
metric
megatonnes
of
sedimentary
material
down
canyon.
Canyon
habitat
now
recovering
from
this
removal
both
seafloor
substrate
and
associated
organisms.
We
measured
post-event
macrofauna
density
together
biomass
sediment
properties
related
these
to
infaunal
bioturbation
activity,
community
oxygen
consumption
(SCOC)
macronutrient
biogeochemical
fluxes.
Three
legacy
sites
were
used
as
reference
along
depth
transect
canyon
axis
at
917,
1249,
1480
m
water
depths.
found
distinct
differences
functioning
between
sites.
While
many
parameters
followed
expected
relationships
decreasing
some
biological
activity
metrics
did
not.
Our
data
suggests
differ
based
on
relative
impact
type
experienced
during
earthquake-triggered,
canyon-flushing
event.
find
SCOC
was
linked
bioturbatory
behaviour
organic
matter
content,
rather
than
taxa
or
biomass.
greatest
shallowest
site,
middle
site
due
elevated
content.
These
observations
provide
wider
benchmark
faunal-mediated
processes
environments
rare
insights
recovery
trajectories
communities
ecosystem
function
after
large
disturbances.
Nature Communications,
Journal Year:
2024,
Volume and Issue:
15(1)
Published: May 10, 2024
Abstract
Rhenium
(Re)
and
uranium
(U)
are
essential
proxies
in
reconstructing
past
oceanic
oxygenation
evolution.
However,
their
removal
continental
shelf
sediments,
hotspots
of
early
diagenesis,
were
previously
treated
as
quantitatively
unimportant
sinks
the
ocean.
Here
we
examine
sedimentary
reductive
Re
U
coupling
with
organic
carbon
decomposition,
utilizing
224
Ra/
228
Th
disequilibria
within
East
China
Sea
shelf.
We
identified
positive
correlations
between
fluxes
rates
sediment
oxygen
consumption
or
decomposition.
These
enable
an
evaluation
global
that
comparable
to
(for
Re)
higher
than
(~4-fold
for
U)
established
suboxic/anoxic
sinks.
findings
suggest
potential
imbalances
modern
budgets
U,
perhaps
a
substantial
underestimation
sources.
Our
study
thus
highlights
critical
yet
overlooked
Journal of Geophysical Research Biogeosciences,
Journal Year:
2025,
Volume and Issue:
130(1)
Published: Jan. 1, 2025
Abstract
Arctic
climate
warming
is
causing
permafrost
thaw
and
erosion,
which
may
lead
to
enhanced
inputs
of
terrestrial
organic
matter
into
Ocean
shelf
sediments.
Degradation
in
sediments
might
contribute
carbon
dioxide
production
bottom
water
acidification.
Yet,
the
degradability
shallow
sediments,
as
well
contribution
input,
poorly
quantified.
Here,
potential
degradation
rates
were
investigated
for
16
surface
from
Kara
Sea,
Laptev
western
East
Siberian
Sea
compared
with
physicochemical
sediment
properties
including
molecular
biomarkers,
stable
radioactive
isotopes,
grain
size.
Aerobic
oxygen
fluxes,
measured
laboratory
incubations
slurry,
showed
high
spatial
variability
correlated
significantly
content
amount
state
matter.
The
dependency
on
declined
increasing
distance
land,
indicating
that
presence
likely
a
constraining
factor
seas.
However,
consumption
rates,
intact
cores,
also
exhibited
substantial
but
not
related
or
influence.
Oxygen
be
more
strongly
influenced
by
situ
redox
conditions.
Together
previous
observations,
our
findings
support
easily
degradable
sea
substantially
aerobic
consumption.
Frontiers in Marine Science,
Journal Year:
2025,
Volume and Issue:
11
Published: Jan. 22, 2025
The
mineralization
of
organic
matter
at
the
sediment
plays
a
crucial
role
in
ecosystem
functioning
by
facilitating
biogeochemical
cycling
carbon
and
nutrients.
This
process
not
only
supports
nutrient
availability
for
primary
production
but
also
regulates
long-term
storage
within
sediments.
To
understand
processes
associated
with
regeneration,
we
estimated
total
diffusive
oxygen
uptake
rates,
benthic
fluxes,
(OC)
budgets
four
sites
semi-enclosed
Jinhae
Bay
(JB).
(TOU)
rates
ranged
from
38.4
to
49.6
mmol
O
2
m
–2
d
–1
,
(DOU)
12.3
±
1.8
15.1
1.4
.
average
ratio
TOU
:
DOU
3.12
3.28
over
JB,
which
suggests
significant
faunal
activities
JB
vertical
flux
45.5
7.0
93.0
25.3
C
-2
mainly
consisted
biodeposits
aquaculture
activities.
burial
into
3.96
1.00
7.17
1.64
efficiencies
were
4.25
15.8%,
indicated
that
deposited
was
either
mineralized
surface
before
or
laterally
transferred
resuspension.
fluxes
1.50
2.07
nitrogen,
0.02
0.05
phosphate,
6.72
9.11
silicate.
nitrogen
phosphate
accounted
82.1
149%
23.1
57.6%,
respectively,
required
levels
water
column.
Our
results
suggest
OC
oxidation
may
significantly
contribute
cycles
tight
benthic–pelagic
coupling
regeneration.
