Research Square (Research Square),
Journal Year:
2023,
Volume and Issue:
unknown
Published: Oct. 11, 2023
Abstract
Determining
the
dynamics
of
organic
carbon
in
subsoil
(SOC,
depth
20–100
cm)
is
important
with
respect
to
global
C
cycle
and
warming
mitigation.
However,
there
still
a
huge
knowledge
gap
spatiotemporal
changes
SOC
this
layer.
We
developed
new
method
spatially
resolve
soil
β
values
for
ecosystems
(cropland,
grassland,
forestland)
at
high
resolution.
first
quantified
spatial
variability
characteristics
these
driving
factors
by
analyzing
1221
profiles
(0–1
m)
globally
distributed
field
measurements
mapped
grid-level
values.
Then
we
evaluated
different
layers
determine
stocks
various
ecosystems.
The
density
cropland,
forestland
were
63.8,
83.3,
100.4
Mg
ha
–1
,
respectively.
decreased
increasing
depth,
ranging
from
5.6
30.8
7.5
40.0
9.6
47.0
forestland.
stock
was
912
Pg
C,
which
an
average
54%
resided
top
0–100
cm
profile.
Our
results
provide
insights
into
untapped
potential
enhance
sequestration
terrestrial
toward
climate
neutralization.
Global Change Biology,
Journal Year:
2024,
Volume and Issue:
30(3)
Published: March 1, 2024
Abstract
Emerging
evidence
points
out
that
the
responses
of
soil
organic
carbon
(SOC)
to
nitrogen
(N)
addition
differ
along
profile,
highlighting
importance
synthesizing
results
from
different
layers.
Here,
using
a
global
meta‐analysis,
we
found
N
significantly
enhanced
topsoil
(0–30
cm)
SOC
by
3.7%
(±1.4%)
in
forests
and
grasslands.
In
contrast,
subsoil
(30–100
initially
increased
with
but
decreased
over
time.
The
model
selection
analysis
revealed
experimental
duration
vegetation
type
are
among
most
important
predictors
across
wide
range
climatic,
environmental,
edaphic
variables.
contrasting
indicate
considering
deep
layers,
particularly
for
long‐term
continuous
deposition.
Finally,
lack
depth‐dependent
modeling
frameworks
has
likely
resulted
overestimation
changes
storage
under
Forest Ecosystems,
Journal Year:
2024,
Volume and Issue:
11, P. 100203 - 100203
Published: Jan. 1, 2024
Soil
organic
carbon
(SOC)
affects
the
function
of
terrestrial
ecosystem
and
plays
a
vital
role
in
global
cycle.
Yet,
large
uncertainty
still
existed
regarding
changes
SOC
stock
quality
with
forest
succession.
Here,
at
1
m
soil
profile
were
investigated
across
subalpine
series,
including
shrub,
deciduous
broad-leaved
forest,
broadleaf-conifer
mixed
middle-age
coniferous
mature
which
located
southeast
Tibetan
Plateau.
The
results
showed
that
ranged
from
9.8
to
29.9
kg·m–2,
exhibited
hump-shaped
response
pattern
successional
series.
highest
lowest
was
observed
shrub
respectively.
had
no
significant
relationships
temperature
litter
stock,
but
positively
correlated
wood
debris
stock.
Meanwhile,
average
percentages
polysaccharides,
lignins,
aromatics
aliphatics
based
on
FTIR
spectroscopy
79.89%,
0.94%,
18.87%
0.29%,
Furthermore,
percentage
polysaccharides
an
increasing
series
except
for
sudden
decreasing
while
proportions
forest.
Consequently,
humification
indices
(HIs)
compared
other
four
stages,
means
worse
than
stages.
In
addition,
recalcitrant
fractions
HIs
decreased
depth,
pattern.
These
findings
demonstrate
higher
high
proportion
(66%
depth
20–100
cm)
better
(lower
HIs)
indicate
deep
have
tremendous
potential
store
needs
more
attention
under
change.
