Environmental Science & Technology,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 10, 2025
Carbonaceous
materials,
including
activated
carbon
and
pyrolytic
carbon,
have
been
recognized
for
about
over
a
decade
as
effective
electron
shuttles
or
conductive
materials
in
promoting
microbial
Fe(III)
mineral
reduction.
However,
recent
studies
reveal
inhibitory
effects,
sparking
debates
their
overall
impact.
We
hypothesized
that
the
physical
contact
between
bacteria
is
an
overlooked
yet
critical
factor
determining
whether
promotes
inhibits
Using
systems
containing
Shewanella
oneidensis
MR-1,
ferrihydrite,
we
investigated
how
carbon-iron
oxide
aggregate
structure
affects
reduction
kinetics.
At
low
carbon-to-iron
ratios
(C/Fe
=
5:7
by
mass),
ferrihydrite
aggregated
with
forming
carbon-encapsulated
particles
suppressed
rates.
Conversely,
at
higher
100:7),
dispersed
on
surface,
enhancing
both
rate
extent
of
Tests
11
different
carbonaceous
(activated
biochar)
all
confirmed
microstructure
iron
oxides─whether
encapsulating
dispersed─on
surfaces
This
insight
resolves
debate
promote
inhibit
enhances
our
understanding
roles
biogeochemical
processes
environmental
remediation.
Environmental Science & Technology,
Год журнала:
2023,
Номер
57(18), С. 7206 - 7216
Опубликована: Апрель 28, 2023
Nitrogenase
is
the
only
known
biological
enzyme
capable
of
reducing
N2
to
bioavailable
NH3.
Most
nitrogenases
use
Mo
as
a
metallocofactor,
while
alternative
cofactors
V
and
Fe
are
also
viable.
Both
geological
bioinformatic
evidence
suggest
an
ancient
origin
Mo-based
nitrogenase
in
Archean,
despite
low
concentration
dissolved
Archean
oceans.
This
apparent
paradox
would
be
resolvable
if
mineral-bound
were
for
nitrogen
fixation
by
diazotrophs.
In
this
study,
bioavailability
Mo,
V,
was
determined
incubating
obligately
anaerobic
diazotroph
Clostridium
kluyveri
with
Mo-,
V-,
Fe-bearing
minerals
(molybdenite,
cavansite,
ferrihydrite,
respectively)
basalt
under
diazotrophic
conditions.
The
results
showed
that
C.
utilized
mineral-associated
metals
express
genes
fix
nitrogen,
measured
reverse
transcription
quantitative
polymerase
chain
reaction
acetylene
reduction
assay,
respectively.
secreted
chelating
molecules
extract
from
minerals.
As
result
microbial
weathering,
mineral
surface
chemistry
significantly
changed,
likely
due
coating
exudates
metal
extraction.
These
provide
important
support
nitrogenase,
profound
implications
coevolution
biosphere
geosphere.
Abstract
Soil
contamination
by
uranium
presents
a
burgeoning
global
environmental
concern,
exerting
detrimental
effects
on
both
agricultural
production
and
soil
health.
Biochar,
carbonaceous
material
derived
from
biomass
pyrolysis,
exhibits
considerable
potential
for
remediating
uranium-contaminated
soils.
However,
comprehensive
review
of
the
biochar
fate
accumulation
in
soil–plant
systems
remains
conspicuously
absent.
In
this
paper,
sources
are
reviewed,
impact
immobilization
detoxification
is
analyzed.
We
reviewed
status
soils
globally
found
that
mining
activities
currently
main
sources.
Further
meta-analysis
revealed
addition
significantly
reduced
bioavailability
shoot
accumulation,
their
effect
value
58.9%
(40.8–76.8%)
39.7%
(15.7–63.8%),
respectively.
Additionally,
enhances
microenvironment,
providing
favourable
conditions
promoting
plant
growth
reducing
mobility.
focused
mechanisms
governing
interaction
between
uranium,
emphasising
roles
played
surface
complexation,
reduction,
ion
exchange,
physical
adsorption.
The
modification
intensifying
these
can
promote
immobilisation
Finally,
alleviates
oxidative
stress
reduces
tissues,
thereby
mitigating
adverse
development.
Overall,
our
highlights
capacity
to
remediate
through
diverse
mechanisms,
valuable
insights
sustainable
remediation.
Highlights
Biochar
mobility
variety
including
limits
its
plants.
Modified
has
been
shown
enhance
effectiveness
immobilising
uranium.
application
not
only
promotes
remediation
but
also
improves
quality.
Graphical
Eco-Environment & Health,
Год журнала:
2024,
Номер
3(1), С. 59 - 76
Опубликована: Янв. 3, 2024
Soil,
the
largest
terrestrial
carbon
reservoir,
is
central
to
climate
change
and
relevant
feedback
environmental
health.
Minerals
are
essential
components
that
contribute
over
60%
of
soil
storage.
However,
how
interactions
between
minerals
organic
shape
transformation
stability
remains
poorly
understood.
Herein,
we
critically
review
primary
mechanisms,
including
sorption,
redox
reaction,
co-precipitation,
dissolution,
polymerization,
catalytic
reaction.
These
interactions,
highly
complex
with
combination
multiple
processes,
greatly
affect
through
following
processes:
(1)
formation
or
deconstruction
mineral-organic
association;
(2)
oxidative
minerals;
(3)
polymerization
(4)
varying
association
according
mineral
transformation.
Several
pieces
evidence
related
turnover
during
interaction
in
real
eco-environment
then
demonstrated.
We
also
highlight
current
research
gaps
outline
priorities,
which
may
map
future
directions
for
a
deeper
mechanisms-based
understanding
storage
capacity
considering
its
minerals.
Environmental Science & Technology,
Год журнала:
2023,
Номер
57(49), С. 20871 - 20880
Опубликована: Ноя. 29, 2023
Organic
acid
is
prevalent
in
underground
environments
and,
against
the
backdrop
of
biogeochemical
cycles
on
Earth,
holds
significant
importance
degradation
contaminants
by
redox-active
minerals.
While
earlier
studies
role
organic
generation
reactive
oxygen
species
(ROS)
primarily
concentrated
electron
shuttle
or
ligand
effects,
this
study
delves
into
combined
impacts
decomposition
and
Mackinawite
(FeS)
oxidation
contaminant
transformation
under
dark
aerobic
conditions.
Using
bisphenol
A
(BPA)
as
a
model,
our
findings
showed
that
oxalic
(OA)
notably
outperforms
other
acids
enhancing
BPA
removal,
attaining
rate
constant
0.69
h-1.
Mass
spectrometry
characterizations,
coupled
with
anaerobic
treatments,
advocate
for
molecule-O2
activation
principal
mechanism
behind
pollutant
transformation.
Comprehensive
results
unveiled
carbon
center
radicals,
initiated
hydroxyl
radical
(•OH)
attack,
serve
primary
agents
oxidation,
accounting
at
least
93.6%
total
•OH
generation.
This
dynamic,
driven
concurrent
formation
carbon-centered
ensures
steady
supply
electrons
ROS
The
obtained
information
highlights
OA
natural
attenuation
pollutants
offers
innovative
strategies
FeS
acid-coupled
decontamination.
Environmental Science & Technology,
Год журнала:
2025,
Номер
unknown
Опубликована: Янв. 2, 2025
Peatlands
store
one-third
of
the
world's
soil
organic
carbon.
Globally
increased
fires
altered
peat
matter
chemistry,
yet
redox
property
and
molecular
dynamics
peat-dissolved
(PDOM)
during
remain
poorly
characterized,
limiting
our
understanding
postfire
biogeochemical
processes.
Clarifying
these
dynamic
changes
is
essential
for
effective
peatland
fire
management.
This
study
demonstrates
temperature-dependent
in
electron
exchange
capacity
(EEC)
PDOM
by
simulating
burning,
significantly
affecting
microbial
iron
reduction.
At
low
temperatures
(200-250
°C),
EEC
remains
constant
releasing
more
phenolic
moieties
to
enhance
electron-donating
(EDC).
Higher
(500
°C)
diminish
90%
consuming
phenolic-quinone
moieties.
Pyrolytic
(pyPDOM)
contributes
40%
soil,
with
this
contribution
declining
at
higher
temperatures.
Phenolic-quinone
primary
redox-active
pyPDOM.
Fourier
transform
ion
cyclotron
resonance
mass
spectrometry
analysis
shows
that
EDC
depends
on
types
than
abundance,
monophenol-like
molecules
(
Environmental Science & Technology,
Год журнала:
2023,
Номер
57(48), С. 19760 - 19771
Опубликована: Ноя. 16, 2023
The
redox
activity
of
Fe-bearing
minerals
is
coupled
with
the
transformation
organic
matter
(OM)
in
dynamic
environments,
but
underlying
mechanism
remains
unclear.
In
this
work,
a
Fe
cycling
experiment
nontronite
(NAu-2),
an
Fe-rich
smectite,
was
performed
via
combined
abiotic
and
biotic
methods,
accompanying
humic
acid
(HA)
as
representative
OM
investigated.
Chemical
reduction
subsequent
reoxidation
NAu-2
produced
abundant
hydroxyl
radicals
(thereafter
termed
·OH)
that
effectively
transformed
chemical
molecular
composition
HA.
More
importantly,
HA
served
more
premium
electron
donor/carbon
source
to
couple
biological
Fe(III)
reoxidized
by
Geobacter
sulfurreducens,
model
Fe-reducing
bacterium.
Destruction
aromatic
structures
formation
carboxylates
were
mechanisms
responsible
for
transforming
into
energetically
bioavailable
substrate.
Relative
unaltered
HA,
increased
extent
bioreduction
105%,
oxidation
even
mineralization
resulting
bleached
microbial
products
cell
debris.
·OH
slightly
decreased
shuttling
capacity
bioreduction.
Our
results
provide
mechanistic
explanation
rapid
driven
redox-fluctuating
environments.