Academic Journal of Environment & Earth Science,
Journal Year:
2023,
Volume and Issue:
5(10)
Published: Jan. 1, 2023
Grassland
is
the
important
terrestrial
ecosystem,
aboveground
biomass
an
indicator
of
productivity
grassland
monitoring
very
to
assessment
current
status
growth
and
conservation
development
resources
Lanzhou
city.
In
this
study,
reflectance
was
extracted
9
vegetation
indexes
calculated
from
Landsat
images
that
combined
with
field
sampling
data
in
city
July-August
2021
construct
two
machine
models
Random
Forest
model
(RF)
eExtreme
Gradient
Boosting
(XGBoost)
chose
best
invert
grass
City
2000
2023
analyze
its
spatial
temporal
dynamics.The
results
study
show
that:
(1)
The
other
bands
except
b5-NIR
band
nine
indices
were
significantly
correlated
by
Pearson
correlation
analysis,
so
remaining
14
factors
selected
as
input
variables.
(2)
Compared
XGBoost
(R2
0.78,
RMSE
37.03),
RF
0.89,
23.28)
has
a
higher
accuracy
it
more
suitable
for
inversion
(3)
time,
average
value
showed
increasing
trend
whole;
space,
decreased
firstly
southeast
northwest
then
increased
City.
area
high
zone
increased,
low
kept
transforming
zone.
This
can
provide
theoretical
reference
technical
support
estimation
protection
ecosystem
Geoderma,
Journal Year:
2023,
Volume and Issue:
440, P. 116738 - 116738
Published: Dec. 1, 2023
Soil
salinization
is
one
of
the
main
factors
contributing
to
land
degradation,
affecting
ecological
equilibrium,
environmental
health,
and
sustainable
development
agriculture.
Due
spatial
temporal
heterogeneity
soil
properties
conditions
in
a
large-scale
region,
monitoring
accuracy
can
be
challenging.
This
study
investigated
whether
classification
diverse
crop
types
on
time
series
improve
prediction
regional
salinity
levels.
Specifically,
we
evaluated
changes
salt
content
(SSC)
under
vegetation
cover
over
Hetao
Irrigation
District
(HID)
using
multi-phase
Sentinel-2
imagery
ground-truth
data
collected
from
June
September
2021
2022.
Focused
sunflower
maize
fields,
this
analyzed
impact
classifying
these
two
examining
four
distinct
SSC
estimation.
Five
indices
were
selected
as
characteristic
parameters
pool
17
(VIs)
13
(SIs)
derived
satellite
images.
Moreover,
three
machine
learning
algorithms
used
establish
estimation
models.
The
findings
underscored
efficacy
considering
different
enhancing
response
sensitivity
spectral
improving
modeling
accuracy.
Among
indices,
VIs
made
more
contributions
model
than
SIs,
achieving
highest
coefficient
determination
(R2)
0.71.
artificial
neural
networks
algorithm
outperformed
other
terms
stability,
yielding
an
optimal
R2
0.72
Root
Mean
Square
Error
(RMSE)
0.15%.
proposed
mapping
approach
that
considers
various
series,
offering
valuable
insights
for
accurately
assessing
salinization,
guiding
strategies
its
prevention
remediation.
Geoderma,
Journal Year:
2023,
Volume and Issue:
439, P. 116697 - 116697
Published: Oct. 24, 2023
Optical
remote
sensing
satellites
provide
rapid
access
to
regional
topsoil
salinization
mapping.
However,
mapping
based
on
spectral
reflectance
is
always
affected
by
background
material
like
vegetation
cover,
straw
mulching
and
soil
types.
In
light
of
these
challenges,
this
study
investigates
the
potential
image
fusion,
where
images
original
bare
pixels
were
combined,
minimize
impact
cover
salinity
A
case
was
presented
for
typical
area
using
synchronized
Sentinel-2
MSI
(named
image)
255
ground-truth
data
collected
in
October
2020,
aligning
with
periods
salt
return.
Furthermore,
obtain
novel
pixels,
multi-temporal
acquired
during
two
distinct
intervals:
March
May
September
November,
spanning
years
from
2018
2021.
The
synthetic
(SYSI)
obtained
extracting
images.
Two
(original,
SYSI)
fused
non-negative
matrix
factorization
(NMF)
method,
named
SYSIfused.
Then,
stacking
machine
algorithm
used
under
different
types,
evaluating
SYSIfused
accuracy
prediction.
results
showed
outperformed
(the
R2
best
models
increased
0.054–0.242,
RMSE
MAE
decreased
0.049–0.780
0.012–0.546,
respectively).
Based
SYSIfused,
order
effect
types
coastal
bog
solonchaks
>
alluvial
cinnamon
coral
saline
overall
samples,
their
roles
improving
model
0.141,
0.085,
0.022,
0.012,
respectively.
Besides,
provided
prediction
performances
(R2
=
0.742,
0.377,
0.362).
This
introduces
concept
merging
SYSI,
resulting
a
significant
improvement
areas
covered
vegetation.
Remote Sensing,
Journal Year:
2024,
Volume and Issue:
16(24), P. 4812 - 4812
Published: Dec. 23, 2024
Soil
salinization
is
a
significant
global
ecological
issue
that
leads
to
soil
degradation
and
recognized
as
one
of
the
primary
factors
hindering
sustainable
development
irrigated
farmlands
deserts.
The
integration
remote
sensing
(RS)
machine
learning
algorithms
increasingly
employed
deliver
cost-effective,
time-efficient,
spatially
resolved,
accurately
mapped,
uncertainty-quantified
salinity
information.
We
reviewed
articles
published
between
January
2016
December
2023
on
sensing-based
prediction
synthesized
latest
research
advancements
in
terms
innovation
points,
data,
methodologies,
variable
importance,
trends,
current
challenges,
potential
future
directions.
Our
observations
indicate
innovations
this
field
focus
detection
depth,
iterations
data
conversion
methods,
application
newly
developed
sensors.
Statistical
analysis
reveals
Landsat
most
frequently
utilized
sensor
these
studies.
Furthermore,
deep
remains
underexplored.
ranking
accuracy
across
various
study
areas
follows:
lake
wetland
(R2
=
0.81)
>
oasis
0.76)
coastal
zone
0.74)
farmland
0.71).
also
examined
relationship
metadata
accuracy:
(1)
Validation
accuracy,
sample
size,
number
variables,
mean
exhibited
some
correlation
with
modeling
while
sampling
type,
time,
maximum
did
not
influence
accuracy.
(2)
Across
broad
range
scales,
large
sizes
may
lead
error
accumulation,
which
associated
geographic
diversity
area.
(3)
inclusion
additional
environmental
variables
does
necessarily
enhance
(4)
Modeling
improves
when
area
exceeds
30
dS/m.
Topography,
vegetation,
temperature
are
relatively
covariates.
Over
past
years,
affected
by
has
been
increasing.
To
further
we
provide
several
suggestions
for
challenges
directions
research.
While
sole
solution,
it
provides
unique
advantages
salinity-related
studies
at
both
regional
scales.
Sustainability,
Journal Year:
2024,
Volume and Issue:
16(18), P. 8011 - 8011
Published: Sept. 13, 2024
The
monitoring
of
maize
health
status
is
crucial
for
achieving
sustainable
agricultural
development.
Canopy
nitrogen
content
(CNC)
essential
the
synthesis
proteins
and
chlorophyll
in
leaves
and,
thus,
significantly
influences
growth
yield.
In
this
study,
we
developed
a
CNC
spectral
estimation
model
based
on
transform-based
dynamic
indices
(TDSI)
random
forest
(RF)
algorithm,
enabling
rapid
canopy
leaves.
A
total
60
leaf
samples
corresponding
field
spectra
were
collected.
Subsequently,
data
transformed
using
centralization
transformation
(CT),
first
derivative
(D1),
second
(D2),
detrend
(DT),
min-max
normalization
(MMN)
methods.
Three
types
band
combination
methods
(band
difference,
ratio,
normalized
difference)
used
to
construct
TDSIs.
Finally,
optimal
TDSI
was
selected
as
independent
variable,
measured
dependent
variable
build
RF
algorithm.
Results
indicated
that
(1)
TDSIs
can
more
accurately
characterize
maize,
with
correlation
coefficient
approximately
102%
higher
than
those
raw
bands.
(2)
included
TDSI1247,1249CT-RI,
TDSI625,641CT-NDI,
TDSI540,703D1-RI,
TDSI514,540D1-RI,
TDSI514,530D1-DI,
TDSI540,697D1-NDI,
TDSI970,1357D2-DI,
TDSI523,1031D2-NDI,
TDSI617,620DT-RI,
TDSI2109,2127MMN-NDI.
(3)
TDSIs,
algorithm
achieved
accuracy
R2
RPIQ
0.92
4.99,
respectively,
representing
maximum
improvement
67.27%
over
traditional
(based
value).
This
study
provides
an
approach
accurate
contributing
development
agriculture.