Remote Sensing,
Journal Year:
2024,
Volume and Issue:
16(21), P. 3924 - 3924
Published: Oct. 22, 2024
Accurate
evapotranspiration
(ET)
estimation
is
crucial
for
understanding
ecosystem
dynamics
and
managing
water
resources.
Existing
methodologies,
including
traditional
techniques
like
the
Penman–Monteith
model,
remote
sensing
approaches
utilizing
Solar-Induced
Fluorescence
(SIF),
machine
learning
algorithms,
have
demonstrated
varying
levels
of
effectiveness
in
ET
estimation.
However,
these
methods
often
face
significant
challenges,
such
as
reliance
on
empirical
coefficients,
inadequate
representation
canopy
dynamics,
limitations
due
to
cloud
cover
sensor
constraints.
These
issues
can
lead
inaccuracies
capturing
ET’s
spatial
temporal
variability,
highlighting
need
improved
techniques.
This
study
introduces
a
novel
approach
enhance
by
integrating
SIF
partitioning
with
Photosynthetically
Active
Radiation
(PAR)
leaf
area
index
(LAI)
data,
TL-LUE
model
(Two-Leaf
Light
Use
Efficiency).
Partitioning
data
into
sunlit
shaded
components
allows
more
detailed
canopy’s
functional
significantly
improving
modelling.
Our
analysis
reveals
advancements
modelling
through
partitioning.
At
Xiaotangshan
Station,
correlation
between
modelled
SIFsu
0.71,
while
SIFsh
0.65.
The
overall
(R2)
combined
(SIF(P))
0.69,
indicating
strong
positive
relationship
at
Station.
correlations
show
notable
patterns,
R2
values
0.89
0.88
Heihe
Daman,
respectively.
findings
highlight
its
impact
Comparing
observed
(PM
model)
demonstrates
substantial
improvements.
against
were
0.68,
0.76,
across
HuaiLai,
Shangqiu,
Yunxiao
Stations.
Modelled
PM
0.75,
0.73,
0.90,
respectively,
three
stations.
results
underscore
model’s
capability
estimations
physiological
data.
innovative
SIF-partitioning
offers
nuanced
perspective
photosynthesis,
providing
accurate
comprehensive
method
diverse
environments.
Remote Sensing,
Journal Year:
2025,
Volume and Issue:
17(8), P. 1361 - 1361
Published: April 11, 2025
The
interplay
between
terrestrial
water
storage
and
vegetation
dynamics
in
arid
regions
is
critical
for
understanding
ecohydrological
responses
to
climate
change
human
activities.
This
study
examines
the
coupling
total
anomaly
(TWSA)
greenness
changes
Hexi
Corridor,
an
region
northwestern
China
consisting
of
three
inland
river
basins—Shule,
Heihe,
Shiyang—from
2002
2022.
Utilizing
TWSA
data
from
GRACE/GRACE-FO
satellites
MODIS
Enhanced
Vegetation
Index
(EVI)
data,
we
applied
a
trend
analysis
partial
correlation
statistical
techniques
assess
spatiotemporal
patterns
their
drivers
across
varying
aridity
gradients
land
cover
types.
results
reveal
significant
decline
Corridor
(−0.10
cm/year,
p
<
0.01),
despite
modest
increase
precipitation
(1.69
mm/year,
=
0.114).
spatial
shows
that
deficits
are
most
pronounced
northern
Shiyang
Basin
(−600
−300
cm
cumulative
TWSA),
while
southern
Qilian
Mountain
exhibit
accumulation
(0
800
cm).
greening
strongest
irrigated
croplands,
particularly
hyper-arid
area.
highlights
distinct
drivers:
wetter
semi-humid
semi-arid
regions,
plays
dominant
role
driving
trends.
Such
rainfall
dominance
gives
way
temperature-
human-dominated
regions.
decoupling
importance
irrigation
activities
warming-induced
atmospheric
demand
co-driving
These
findings
suggest
expansion
cause
satellite-observed
greening,
it
exacerbates
stress
through
increased
evapotranspiration
groundwater
depletion,
water-limited
zones.
reveals
complex
drylands,
emphasizing
need
holistic
view
dryland
context
global
warming,
escalating
freshwater
resources,
efforts
achieving
sustainable
development.
Annals of Botany,
Journal Year:
2024,
Volume and Issue:
134(3), P. 501 - 510
Published: June 3, 2024
Abstract
Background
and
Aims
Leaf
area
(A)
is
a
crucial
indicator
of
the
photosynthetic
capacity
plants.
The
Montgomery
equation
(ME),
which
hypothesizes
that
A
proportional
to
product
leaf
length
(L)
width
(W),
valid
tool
for
non-destructively
measuring
many
broadleaved
At
present,
methods
used
compute
L
W
ME
can
be
broadly
divided
into
two
kinds:
using
computer
recognition
manually.
However,
potential
difference
in
prediction
accuracy
either
method
has
not
been
thoroughly
examined
previous
studies.
Methods
In
present
study,
we
measured
540
Alangium
chinense
leaves,
489
Liquidambar
formosana
leaves
215
Liriodendron
×
sinoamericanum
utilizing
manual
measurement
determine
W.
was
fit
data
determined
by
methods,
goodness
fits
were
compared.
errors
analysed
examining
correlations
with
symmetry
indices
(areal
ratio
left
side
right
side,
standardized
index
bilateral
asymmetry),
as
well
shape
complexity
(the
dissection
index).
Key
Results
results
indicate
there
neglectable
estimation
between
methods.
This
further
validates
an
effective
estimating
tree
species,
including
those
lobes.
Additionally,
significantly
influenced
A.
Conclusions
These
show
use
field
are
both
feasible,
although
influence
should
considered
when
applying
estimate
future.
Agronomy,
Journal Year:
2025,
Volume and Issue:
15(1), P. 133 - 133
Published: Jan. 8, 2025
Solar-induced
chlorophyll
fluorescence
(SIF),
as
a
direct
indicator
of
vegetation
photosynthesis,
offers
more
accurate
measure
plant
photosynthetic
dynamics
than
traditional
indices.
However,
the
current
SIF
satellite
products
have
low
spatial
resolution,
limiting
their
application
in
fine-scale
agricultural
research.
To
address
this,
we
leveraged
MODIS
data
at
1
km
including
bands
b1,
b2,
b3,
and
b4,
alongside
indices
such
NDVI,
EVI,
NIRv,
OSAVI,
SAVI,
LAI,
FPAR,
LST,
covering
October
2018
to
May
2020
for
Shandong
Province,
China.
Using
Random
Forest
(RF)
model,
downscaled
from
0.05°
based
on
invariant
scaling
theory,
focusing
winter
wheat
growth
cycle.
Various
machine
learning
models,
CNN,
Stacking,
Extreme
Trees,
AdaBoost,
GBDT,
were
compared,
with
yielding
best
performance,
achieving
R2
=
0.931,
RMSE
0.052
mW/m2/nm/sr,
MAE
0.031
mW/m2/nm/sr
2018–2019
0.926,
0.058
0.034
2019–2020.
The
showed
strong
correlation
TanSIF
GOSIF
(R2
>
0.8),
consistent
trends
GPP
further
confirmed
reliability
product.
Additionally,
time
series
analysis
Province’s
wheat-growing
areas
revealed
0.8)
between
multiple
indices,
underscoring
its
utility
regional
crop
monitoring.
Journal of Geophysical Research Biogeosciences,
Journal Year:
2025,
Volume and Issue:
130(2)
Published: Jan. 29, 2025
Abstract
Spring
and
summer
vegetation
productivity
in
Siberia
shows
opposing
responses
to
warmer
spring.
warming
causes
excessive
growth
earlier
start
of
photosynthesis,
enhancing
However,
this
leads
reduced
the
following
season
(i.e.,
summer)
through
soil
moisture
depletion.
To
understand
how
an
exceptional
spring
heatwave
(HW)
affected
ecosystem
carbon
uptake,
we
investigated
spatiotemporal
cascade
gross
primary
production
(GPP)
multiple
climate
variables
over
2020,
using
a
satellite‐retrieved
GPP
product
(GOSIF‐GPP)
ERA5‐Land
reanalysis
data
set
for
2001–2020.
Results
showed
positive
impact
anomalous
on
annual
(GPP
ann
).
from
GOSIF‐GPP
West
(55°–70°N,
50°–90°E)
was
enhanced
by
up
10%
above
2001–2019
average
despite
continued
dry
conditions
May
August.
In
East
(55–70°N,
90–130°E),
increases
June
were
sufficient
compensate
marked
reduction
July
due
negative
anomaly
radiation.
addition,
higher
sensitivity
temperature
than
suggests
that
increase
coupled
with
strong
respective
might
be
more
pronounced
western
region,
as
observed
2020.
Our
results
indicate
trend
spring,
combined
possible
extreme
heat
events,
could
elevate
uptake
Siberia,
particularly
Siberia.
Further,
case
study
HW
event
occurred
2020
can
provide
useful
insight
understanding
future
change
Journal of Remote Sensing,
Journal Year:
2025,
Volume and Issue:
5
Published: Jan. 1, 2025
Accurate
estimation
of
gross
primary
production
(GPP)
terrestrial
vegetation
is
crucial
for
comprehending
the
carbon
dynamics.
To
date,
there
still
no
consensus
on
magnitude
and
seasonality
global
GPP
among
major
products,
underscoring
necessity
to
improve
models
higher
accuracy
estimates.
Here,
we
introduce
an
improved
Vegetation
Photosynthesis
Model
(VPM
v3.0),
which
incorporates
site-specific
apparent
optimum
temperature
photosynthesis,
leaf-trait-based
light
absorption
(flat
leaf
vs.
needle
leaf),
water
stress
estimation.
The
VPM
simulation
driven
by
Moderate
Resolution
Imaging
Spectroradiometer
images
ERA5-Land
climate
dataset.
We
evaluate
v3.0
using
from
205
eddy
flux
tower
sites
across
11
land
cover
types
(1,658
site-years)
(GPP
EC
),
as
well
TROPOspheric
monitoring
instrument
(TROPOMI)
solar-induced
fluorescence
(SIF)
product
2018
2021.
slope,
R
2
,
root
mean
square
error
between
VPM-v3
)
are
0.97,
0.78,
1.46
gC
m
−2
day
−1
respectively.
shows
high
temporal
consistency
with
TROPOMI
SIF.
provides
estimates
at
most
evaluated
than
v2.0.
Comparisons
other
products
reveal
both
spatial–temporal
discrepancies.
These
findings
clearly
indicate
in
estimating
GPP,
making
it
suitable
generating
datasets.