Frontiers in Microbiology,
Journal Year:
2024,
Volume and Issue:
15
Published: July 9, 2024
The
nitrogen
(N)
cycle
is
the
foundation
of
biogeochemistry
on
Earth
and
plays
a
crucial
role
in
global
climate
stability.
It
one
most
important
nutrient
cycles
high-altitude
lakes.
almost
entirely
dependent
redox
reactions
mediated
by
microorganisms.
However,
cycling
microbial
communities
saline
lakes
Qinghai-Tibet
Plateau
(QTP),
world's
"third
pole"
has
not
been
investigated
extensively.
In
this
study,
we
used
metagenomic
approach
to
investigate
four
pristine
Altun
mountain
QTP.
We
observed
that
Environmental Science & Technology,
Journal Year:
2023,
Volume and Issue:
57(40), P. 15014 - 15025
Published: Sept. 27, 2023
Intensive
mariculture
activities
result
in
eutrophication
and
enhance
coastal
deoxygenation.
Deoxygenation
profoundly
influences
nitrate
reduction
processes
further
the
fate
of
nitrogen
(N)
systems.
Herein,
15N
isotope
labeling,
real-time
PCR,
high-throughput
sequencing
techniques
were
jointly
used
to
investigate
participation
seasonal
dynamics
sediment
pathways
succession
functional
microbial
communities
during
development
deoxygenation
a
aquaculture
zone.
Denitrification
dominated
benthic
(46.26-80.91%).
Both
denitrification
dissimilatory
ammonium
significantly
enhanced
by
summer
(dissolved
oxygen
levels
fell
2.94
±
0.28
mg
L-1),
while
anammox
remained
unchanged.
The
abundance
nitrous
oxide
reductase
gene
nosZ
increased
community
was
sensitive
deoxygenation,
with
Azospirillum
Ruegeria
accounting
for
majority.
Pelobacter
overwhelming
nrfA
(encoding
nitrite
reductase)
community,
which
less
affected
variations
driven
bottom
water
combined
temperature,
chlorophyll
a,
abundances
compositions.
Our
results
implicated
that
oxygen-deficient
zones
could
be
substantial
N
sinks
ecosystems
important
balance.
Effective
management
measures
need
developed
avoid
exacerbation
maintain
sustainable
mariculture.
Geoderma,
Journal Year:
2023,
Volume and Issue:
431, P. 116362 - 116362
Published: Jan. 30, 2023
Wide
and
rapid
Spartina
alterniflora
invasion
has
threatened
the
sustainability
of
coastal
wetlands
China,
a
significant
impact
on
sediment
biogeochemical
cycle.
However,
effects
exotic
dissimilatory
nitrates
(NOx−)
reduction
processes
mechanisms
underlying
these
pathways
in
mangrove
have
not
been
well
studied.
Here,
denitrification
(DEN),
anaerobic
ammonium
oxidation
(ANA)
nitrate
to
(DNRA)
rates,
contributions
(DEN%,
ANA%,
DNRA%),
associated
functional
genes
(nirS,
anammox
16S
rRNA
nrfA)
controlling
factors
were
investigated
surface
sediments
(0–5
cm)
communities
ecotone
Zhangjiang
Estuary,
China.
Significant
spatial
differences
DEN,
DNRA,
DEN%,
DNRA%
found
among
different
plant
(p
<
0.05
for
all).
DEN
is
dominant
pathway
NOx−
community
(87–89
%)
(75–78
%),
while
(41–51
DNRA
(36–51
compete
with
each
other
community.
Organic
matter
was
most
dominating
factor
rates.
Without
accounting
confounding
factors,
significantly
reduced
nitrogen
retention
index
(NIRI),
causing
large
amount
(N)
loss
wetlands.
We
estimated
that
increased
N-loss
(831.09
±
55.16
t
N
yr−1)
but
(783.48
37.73
habitats
China
within
last
40
years
(1980–2020).
Thus,
enhances
reducing
wetlands,
which
may
threaten
buffer
function
wetland
pools
protection
estuarine
ecosystems.
Limnology and Oceanography,
Journal Year:
2025,
Volume and Issue:
unknown
Published: March 13, 2025
Abstract
Tidal
wetland
reclamation
is
a
worldwide
issue
that
profoundly
alters
ecological
functions
and
ecosystem
service
provisions;
however,
its
impacts
on
sediment
microbial
communities
remain
poorly
understood.
Here,
we
investigated
the
spatial
seasonal
patterns
of
greenhouse
gas
(GHG)
production
in
response
to
land
use
change
mangrove
wetlands
elucidated
underlying
mechanisms
by
integrating
environmental
parameters
community
characteristics.
In
time
period
studied,
substantially
reduced
organic
matter
content,
richness
diversity,
CO
2
rates.
Converting
mangroves
drier
cover
types,
namely
orchard
vegetable
field,
significantly
diminished
reducing
substrates
(sulfide,
Fe
2+
,
NH
4
+
),
network
complexity
stability,
CH
rates,
while
increasing
N
O
contrast,
these
showed
opposite
trend
following
conversion
flooded
aquaculture
pond.
Overall
GHG
rate
was
399.8
mg
e
kg
−1
d
which
respectively
decreased
68.83%,
69.86%,
30.84%
orchard,
Microbial
stability
were
strongly
related
rates
O,
rather
than
can
be
better
indicators
specialized
(CH
production).
Therefore,
preserving
“interaction”
could
important
mitigate
negative
effects
diversity
loss
caused
human
activities
aquatic
environments.
Future
research
should
consider
conditions
composition,
interactions,
gain
comprehensive
understanding
functions.
