IEEE Transactions on Geoscience and Remote Sensing,
Journal Year:
2023,
Volume and Issue:
61, P. 1 - 19
Published: Jan. 1, 2023
Vegetation
water
status,
an
important
physiological
characteristic
of
vegetation,
lacked
a
global-scale
estimate
method.
In
this
study,
global
vegetation
moisture
relative
index
(VMRI)
was
established
based
on
the
optical
depth
(VOD)
and
leaf
area
compared
to
live
fuel
content
(LFMC)
in-situ
measurements
environmental
factors
(soil
from
different
depths,
precipitation,
vapor
pressure
deficit,
ratio
actual
potential
evapotranspiration,
self-calibrating
Palmer
drought
severity
index).
Validation
using
LFMC
indicated
that
VMRI
could
characterize
status
(R
median
=
0.37)
establishment
method
eliminate
influence
aboveground
biomass
in
VOD.
The
results
correlated
comparison
between
showed
positive
significant
correlations
most
regions.
Besides,
more
with
shrublands
grasslands
(e.g.,
R
xmlns:xlink="http://www.w3.org/1999/xlink">mean
0.38
multi-depth
soil
moisture)
than
forests
savannas
0.15),
water-limited
regions
0.33)
were
higher
those
non-water-limited
0.18).
Moreover,
deeper
provided
information
above
60°N.
Furthermore,
trends
displayed
synchronization,
about
60%
pixels
showing
same
trend
85%
same-trend
decreasing
Particularly,
interannual
variations
time-lagged
responses
drought.
Overall,
provides
new
measurement-independent
estimation
for
affected
by
multiple
at
scale.
Forests,
Journal Year:
2025,
Volume and Issue:
16(3), P. 449 - 449
Published: March 2, 2025
Forests
play
a
key
role
in
carbon
sequestration
and
oxygen
production.
They
significantly
contribute
to
peaking
neutrality
goals.
Accurate
estimation
of
forest
stocks
is
essential
for
precise
understanding
the
capacity
ecosystems.
Remote
sensing
technology,
with
its
wide
observational
coverage,
strong
timeliness,
low
cost,
stock
research.
However,
challenges
data
acquisition
processing
include
variability,
signal
saturation
dense
forests,
environmental
limitations.
These
factors
hinder
accurate
estimation.
This
review
summarizes
current
state
research
on
from
two
aspects,
namely
remote
methods,
highlighting
both
advantages
limitations
various
sources
models.
It
also
explores
technological
innovations
cutting-edge
field,
focusing
deep
learning
techniques,
optical
vegetation
thickness
impact
forest–climate
interactions
Finally,
discusses
including
issues
related
quality,
model
adaptability,
stand
complexity,
uncertainties
process.
Based
these
challenges,
paper
looks
ahead
future
trends,
proposing
potential
breakthroughs
pathways.
The
aim
this
study
provide
theoretical
support
methodological
guidance
researchers
fields.
International Journal of Geographical Information Science,
Journal Year:
2023,
Volume and Issue:
37(11), P. 2437 - 2453
Published: Oct. 9, 2023
The
Geographical
Detector
Model
(GDM)
is
a
popular
statistical
toolkit
for
geographical
attribution
analysis.
Despite
the
striking
resemblance
of
q-statistic
in
GDM
to
R-squared
linear
regression
models,
their
explicit
connection
has
not
yet
been
established.
This
study
proves
that
reduces
into
under
framework.
Under
and
moderate-to-strong
spatial
autocorrelation,
Monte
Carlo
simulation
results
show
tends
underestimate
importance
variables.
In
addition,
an
almost
perfect
power
law
relationship
present
between
percentage
bias
degree
autocorrelations,
indicating
presence
fast
uplifting
response
increasing
levels
autocorrelations.
We
propose
integrated
approach
variable
quantification
by
bringing
together
econometrics
model
game
theory
based-Shapley
value
method.
By
applying
our
proposed
methodology
case
land
desertification
African,
it
found
human
activity
affect
both
directly
indirectly.
However,
such
effects
appear
be
underestimated
or
undistinguished
classic
GDM.
Environmental Research Letters,
Journal Year:
2024,
Volume and Issue:
19(3), P. 034019 - 034019
Published: Feb. 12, 2024
Abstract
Studying
vegetation
water
content
(VWC)
dynamics
is
essential
for
understanding
plant
growth,
and
carbon
cycles,
ecosystem
stability.
However,
acquiring
field-based
VWC
estimates,
consistently
through
space
time,
challenging
due
to
time
resource
constraints.
This
study
investigates
the
potential
of
Sentinel-1
C-band
Synthetic
Aperture
Radar
(SAR)
data
estimating
in
natural
ecosystems
central
Brazil.
We
assessed
(i)
how
well
SAR
can
capture
variations
over
three
different
types
(i.e.
dry
waterlogged
grasslands,
savannas)
(ii)
studied
respond
seasonal
periods
terms
content.
Field
from
82
plots,
distributed
across
revisited
four
seasons,
were
used
calibrate
validate
a
model
estimation.
The
calibrated
model,
with
an
R
2
0.52
RMSE
0.465
kg
m
−2
,
was
then
applied
backscatter
generate
monthly
maps
grassland
savanna
at
30
spatial
resolution
between
April
2015
September
2023.
These
maps,
combined
rainfall
evapotranspiration
data,
provided
insights
into
shortage
during
season
community
scale.
More
specifically,
savannas
showed
be
better
able
retain
higher
levels
season,
probably
holding
capacity
woody
component
together
its
deep-root
system
ability
access
deeper
groundwater.
research
demonstrates
monitoring
ecosystems,
allowing
future
studies
assess
ecosystems’
response
drought
events
changes
their
functioning,
ultimately
supporting
land
management
decisions.
Remote Sensing,
Journal Year:
2024,
Volume and Issue:
16(15), P. 2793 - 2793
Published: July 30, 2024
Vegetation
water
content
(VWC)
is
a
crucial
parameter
for
evaluating
vegetation
growth,
climate
change,
natural
disasters
such
as
forest
fires,
and
drought
prediction.
Spaceborne
global
navigation
satellite
system
reflectometry
(GNSS-R)
has
become
valuable
tool
soil
moisture
(SM)
biomass
remote
sensing
(RS)
due
to
its
higher
spatial
resolution
compared
with
microwave
measurements.
Although
previous
studies
have
confirmed
the
enormous
potential
of
spaceborne
GNSS-R
monitoring,
utilization
this
technology
fuse
multiple
RS
parameters
retrieve
VWC
not
yet
mature.
For
purpose,
paper
constructs
local
high-spatiotemporal-resolution
retrieval
model
that
integrates
key
information,
bistatic
radar
cross
section
(BRCS),
effective
scattering
area,
CYGNSS
variables,
surface
auxiliary
based
on
five
ensemble
machine
learning
(ML)
algorithms
(i.e.,
bagging
tree
(BT),
gradient
boosting
decision
(GBDT),
extreme
(XGBoost),
random
(RF),
light
(LightGBM)).
We
extensively
tested
performance
different
models
using
SMAP
ancillary
data
validation
data,
results
show
root
mean
square
errors
(RMSEs)
BT,
XGBoost,
RF,
LightGBM
in
are
better
than
0.50
kg/m2.
Among
them,
BT
RF
performed
best
localized
retrieval,
RMSE
values
Conversely,
XGBoost
exhibits
worst
performance,
an
0.85
In
terms
RMSE,
demonstrates
improvements
70.00%,
52.00%,
32.00%
over
LightGBM,
GBDT
models,
respectively.