Frontiers in Marine Science,
Год журнала:
2025,
Номер
12
Опубликована: Фев. 3, 2025
To
determine
the
excess
of
dissolved
dinitrogen
gas
(ΔN
2
>
0
indicates
loss
bioavailable
nitrogen)
in
water
column
Baltic
Proper,
we
measured
N
/Ar
ratios
below
halocline
at
19
stations
during
different
seasons
between
2017
and
2021.
ΔN
concentrations
ranged
from
1.0
to
32.6
µmol
L
-1
for
all
sites.
A
significant
spatial
difference
(p
=
0.0001)
was
observed,
with
highest
values
found
Gotland
Deep.
The
seasonal
changes
were
statistically
0.005)
observed
winter.
our
knowledge,
this
is
first
study
showing
variability
on
a
large
scale
Proper.
Our
findings
suggest
that
cumulative
nitrogen
via
denitrification
anammox
an
important
mechanism
Sea
cycle.
accumulated
signal
production
is,
however,
not
uniform
across
exhibiting
variabilities.
This
calls
future,
investigations
broad
resolution
which
focus
rates
column,
by
utilizing
consistent
methodological
approach.
It
essential
ensure
accurate
representation
loss,
turn
managing
eutrophication
maintaining
good
environmental
status
Sea.
Proceedings of the Royal Society A Mathematical Physical and Engineering Sciences,
Год журнала:
2021,
Номер
477(2247), С. 20200824 - 20200824
Опубликована: Март 1, 2021
Iodine
is
a
critical
trace
element
involved
in
many
diverse
and
important
processes
the
Earth
system.
The
importance
of
iodine
for
human
health
has
been
known
over
century,
with
low
diet
being
linked
to
goitre,
cretinism
neonatal
death.
Research
last
few
decades
shown
that
significant
impacts
on
tropospheric
photochemistry,
ultimately
impacting
climate
by
reducing
radiative
forcing
ozone
(O
3
)
air
quality
extreme
O
concentrations
polluted
regions.
naturally
present
ocean,
predominantly
as
aqueous
iodide
iodate.
rapid
reaction
sea-surface
believed
be
largest
single
source
gaseous
atmosphere.
Due
increased
anthropogenic
,
this
release
have
dramatically
twentieth
much
factor
3.
Uncertainties
marine
distribution
global
cycle
are,
however,
major
constraints
effective
prediction
how
emissions
its
biogeochemical
may
change
future
or
changed
past.
Here,
we
synthesis
recent
results
our
team
others
which
bring
fresh
perspective
understanding
cycle.
In
particular,
suggest
climate-induced
oceanographic
changes
could
result
surface
implications
atmospheric
climate.
Frontiers in Marine Science,
Год журнала:
2022,
Номер
9
Опубликована: Фев. 2, 2022
Bacteria
play
a
crucial
role
in
marine
biogeochemistry
by
releasing,
consuming
and
transforming
organic
matter.
Far
from
being
isolated
entities,
bacteria
are
involved
numerous
cell–cell
interactions.
Among
such
interactions,
quorum
sensing
(QS)
allows
to
operate
unison,
synchronizing
their
actions
through
chemical
communication.
This
review
aims
explore
synthesize
our
current
knowledge
of
the
involvement
QS
regulation
bacterial
processes
that
ultimately
impact
biogeochemical
cycles.
We
first
describe
principles
communication
renewed
interest
its
study
environments.
Second,
we
highlight
microniches
where
is
most
likely
occur
due
high
densities
also
hotspots
bacterially
mediated
transformations.
Many
groups
colonizing
these
harbor
various
systems.
Thereafter,
relevant
QS-regulated
environments,
building
on
research
performed
both
complex
assemblages
bacteria.
pathways
have
been
shown
directly
regulate
matter
degradation,
carbon
allocation
nutrient
acquisition
but
structure
community
composition
mediating
colonization
microbial
Finally,
discuss
limitations
future
perspectives
better
characterize
link
between
expression
mediation
The
picture
drawn
this
highlights
as
one
pivotal
mechanisms
impacting
functions
oceans,
paving
way
for
constrain
Abstract
Microbial
metabolism
upholds
a
fundamental
role
in
the
sustainability
of
water
ecosystems.
However,
how
microorganisms
surviving
low-concentration
substrate
environments,
including
existence
emerging
compounds
interest,
remains
unclear.
In
this
review,
microbial
strategies
for
concentrating,
utilizing,
and
metabolizing
low
concentration
substrates
were
summarized.
Microorganisms
develop
substrate-concentrating
at
both
cell
aggregate
levels
substrate-limited
settings.
Following,
uptake
transport
are
facilitated
by
adjusting
physiological
characteristics
shifting
affinities.
Finally,
metabolic
pathways,
such
as
mixed-substrate
utilization,
syntrophic
metabolism,
dynamic
response
to
nutrient
variation,
population
density-based
mechanisms
allow
efficiently
utilize
adapt
challenging
oligotrophic
environments.
All
these
will
underpin
devising
new
approaches
tackle
environmental
challenges
drive
ecosystems,
particularly
managing
contaminants
(i.e.,
micropollutants).
Frontiers in Marine Science,
Год журнала:
2024,
Номер
10
Опубликована: Янв. 9, 2024
The
distribution
of
iodine
in
the
surface
ocean
–
which
iodide-iodine
is
a
large
destructor
tropospheric
ozone
(O
3
)
can
be
attributed
to
both
situ
(i.e.,
biological)
and
ex
mixing)
drivers.
Currently,
uncertainty
regarding
rates
mechanisms
iodide
(I
-
oxidation
render
it
difficult
distinguish
importance
reactions
vs
mixing
driving
iodine’s
distribution,
thus
leading
climatological
atmospheric
models.
It
has
been
hypothesized
that
reactive
oxygen
species
(ROS),
such
as
superoxide
2
•−
or
hydrogen
peroxide
(H
O
),
may
needed
for
I
occur
at
sea
surface,
but
this
yet
demonstrated
natural
marine
waters.
To
test
role
ROS
redox
transformations,
shipboard
isotope
tracer
incubations
were
conducted
part
Bermuda
Atlantic
Time
Series
(BATS)
Sargasso
Sea
September
2018.
Incubation
trials
evaluated
effects
,
H
on
transformations
over
time
euphotic
sub-photic
depths.
Rates
assessed
using
129
(t
1/2
~15.7
Myr)
added
all
incubations,
I/
127
ratios
individual
IO
).
Our
results
show
lack
within
resolution
our
approach
i.e.,
<2.99
nM/day,
<1091.4
nM/yr.
In
addition,
we
present
new
data
from
BATS
compare
speciation
profiles
two
previous
studies
BATS,
demonstrate
long-term
stability.
These
indicate
processes,
vertical
mixing,
play
an
important
broader
species’
similar
regions.
Frontiers in Microbiology,
Год журнала:
2020,
Номер
11
Опубликована: Апрель 15, 2020
Humic
substances
are
redox-active
organic
molecules,
which
play
pivotal
roles
in
several
biogeochemical
cycles
due
to
their
electron-transferring
capacity
involving
multiple
abiotic
and
microbial
transformations.
Based
on
the
redox
properties
of
humic
substances,
metabolic
capabilities
microorganisms
reduce
oxidize
them,
we
hypothesized
that
they
could
mediate
anaerobic
oxidation
methane
(AOM)
coupled
reduction
nitrous
oxide
(N2O)
wetland
sediments.
This
study
provides
lines
evidence
indicating
coupling
between
AOM
N2O
through
an
extracellular
electron
transfer
mechanism
mediated
by
active
functional
groups
(e.g.,
quinones).
We
found
microbiota
a
sediment
collected
from
Sisal
(Yucatán
Peninsula,
southeastern
Mexico)
was
able
(4.6
±
0.5
μmol
g
sed.-1
day-1)
when
reduced
were
provided
as
donor
close
stoichiometric
relationship.
Furthermore,
enrichment
derived
achieved
simultaneous
13CH4
(1.3
0.1
13CO2
(25.2
day-1),
significantly
dependent
presence
shuttle.
Taxonomic
characterization
based
16S
rRNA
gene
sequencing
revealed
Acinetobacter
(a
ɣ-proteobacterium),
Rice
Cluster
I
Methanocellaceae
uncultured
archaeon
Methanomicrobiaceae
family
microbes
potentially
involved
linked
substances.
The
findings
reported
here
suggest
might
important
role
prevent
emission
greenhouse
gases
(CH4
N2O)
Further
efforts
evaluate
feasibility
this
novel
under
natural
conditions
prevailing
ecosystems
must
be
considered
future
studies.
