Remote Sensing,
Journal Year:
2022,
Volume and Issue:
14(21), P. 5627 - 5627
Published: Nov. 7, 2022
Soil
salinization
is
one
of
the
major
degradation
processes
threatening
food
security
and
sustainable
development.
Detailed
soil
salinity
information
increasingly
needed
to
tackle
this
global
challenge
for
improving
management.
Soil-visible
near-infrared
(Vis-NIR)
spectroscopy
has
been
proven
be
a
potential
solution
estimating
soil-salinity-related
(i.e.,
electrical
conductivity,
EC)
rapidly
cost-effectively.
However,
previous
studies
were
mainly
conducted
at
field,
regional,
or
national
scale,
so
application
Vis-NIR
scale
needs
further
investigation.
Based
on
an
extensive
open
spectral
library
(61,486
samples
with
both
EC
spectra),
we
compared
four
predictive
models
(PLSR,
Cubist,
Random
Forests,
XGBoost)
in
EC.
Our
results
indicated
that
XGBoost
had
best
model
performance
(R2
0.59,
RMSE
1.96
dS
m−1)
predicting
whereas
PLSR
relatively
limited
ability
0.39,
2.41
m−1).
The
also
showed
auxiliary
environmental
covariates
coordinates,
elevation,
climatic
variables)
could
greatly
improve
prediction
accuracy
by
models,
performed
0.71,
1.65
outcomes
study
provide
valuable
reference
broad-scale
coupling
spectroscopic
technique
easily
obtainable
covariates.
Geoderma,
Journal Year:
2022,
Volume and Issue:
429, P. 116128 - 116128
Published: Nov. 10, 2022
Soil
organic
carbon
(SOC)
prediction
from
remote
sensing
is
often
hindered
by
disturbing
factors
at
the
soil
surface,
such
as
photosynthetic
active
and
non–photosynthetic
vegetation,
variation
in
moisture
or
surface
roughness.
With
increasing
amount
of
freely
available
satellite
data,
recent
studies
have
focused
on
stabilizing
reflectance
building
composites
using
time
series
images.
Although
composite
imagery
has
demonstrated
its
potential
SOC
prediction,
it
still
not
well
established
if
resulting
spectra
mirror
fingerprint
optimal
conditions
to
predict
topsoil
properties
(i.e.
a
smooth,
dry
bare
soil).
We
collected
303
photos
surfaces
Belgian
loam
belt
where
five
main
classes
were
distinguished:
smooth
seeded
soils,
crusts,
partial
cover
growing
crop,
moist
soils
crop
residue
cover.
Reflectance
then
extracted
Sentinel–2
images
coinciding
with
date
photos.
After
was
removed
an
NDVI
<
0.25,
Normalized
Burn
Ratio
(NBR2)
calculated
characterize
threshold
NBR2
0.05
found
be
able
separate
unfavorable
i.e.
wet
covered
residues.
Additionally,
we
that
normalizing
dividing
each
band
mean
all
spectral
bands)
allows
for
cancelling
albedo
shift
between
crusts
seed–bed
conditions.
built
exposed
southern
Belgium
part
Noord-Holland
Flevoland
Netherlands
(covering
spring
periods
2016–2021).
used
per
pixel
content
means
Partial
Least
Squares
Regression
Model
(PLSR)
10–fold
cross–validation.
The
uncertainty
models
assessed
via
interval
ratio
(PIR).
cross
validation
model
gave
satisfactory
results
(mean
100
bootstraps:
efficiency
coefficient
(MEC)
=
0.48
±
0.07,
RMSE
3.5
0.3
g
C
kg–1,
RPD
1.4
0.1
RPIQ
1.9
0.3).
maps
show
decreases
when
number
scenes
increases,
reaches
minimum
least
six
are
PIR
pixels
12.4
while
predicted
14.1
kg–1).
against
independent
data
set
showed
median
difference
0.5
kg–1
2.8
measured
(average
13.5
kg–1)
contents
field
scale.
Overall,
this
compositing
method
shows
both
realistic
within
regional
patterns.
Geoderma,
Journal Year:
2023,
Volume and Issue:
432, P. 116413 - 116413
Published: March 8, 2023
Minerals
control
many
soil
functions
and
play
a
crucial
role
in
addressing
global
existential
issues.
Measuring
the
abundance
of
minerals
is
laborious,
costly,
time-consuming
task;
however,
spectroscopy
can
be
useful
tool
to
overcome
this
issue.
This
work
aimed
map
major
mineralogical
components
soils
Brazil
from
surface
1
m
deep
at
spatial
resolution
30
m.
Spectral
data
Brazilian
Soil
Library
with
Vis-NIR-SWIR
was
used
estimate
haematite,
goethite,
kaolinite,
gibbsite.
These
were
spatialized
using
digital
mapping
techniques.
We
also
developed
novel
framework
obtain
bare
reflectance
for
areas
without
natural
or
anthropic
exposure
(continuous
image)
it
as
covariate.
their
abundances
successfully
estimated
by
reflectance.
Haematite
predictions
presented
most
accurate
results
Random
Forest
models,
followed
gibbsite,
goethite.
The
validation
reference
found
R2
0.64
(haematite),
0.40
(goethite),
0.20
(kaolinite/Kt),
0.29
(gibbsite/Gbs),
(Kt/Kt
+
Gbs).
resulting
maps
accordance
geology,
pedology,
climate,
relief
revealed
distribution
mineral
finer
than
existing
geological
pedological
maps,
reaching
farm
level
detail.
Remote Sensing,
Journal Year:
2023,
Volume and Issue:
15(4), P. 876 - 876
Published: Feb. 4, 2023
Precise
knowledge
about
the
soil
organic
carbon
(SOC)
content
in
cropland
soils
is
one
requirement
to
design
and
execute
effective
climate
food
policies.
In
digital
mapping
(DSM),
machine
learning
algorithms
are
used
predict
properties
from
covariates
derived
traditional
mapping,
elevation
models,
land
use,
Earth
observation
(EO).
However,
such
DSM
models
trained
for
a
specific
dataset
region
have
so
far
only
allowed
limited
general
statements
be
made
that
would
enable
transferred
different
regions.
this
study,
we
test
transferability
of
SOC
using
five
covariate
groups:
multispectral
reflectance
composites
(satellite),
legacy
data
(soil),
model
derivatives
(terrain),
parameters
(climate),
combined
(combined).
The
was
analyzed
two
federal
states
southern
Germany:
Bavaria
Baden-Wuerttemberg.
First,
baseline
were
each
state
with
performing
best
both
cases
(R2
=
0.68/0.48).
Next,
tested
samples
other
whose
not
during
calibration.
Only
satellite
transferable,
but
accuracy
declined
cases.
final
step,
(mixed-data
models)
applied
separately.
This
process
significantly
improved
accuracies
satellite,
terrain,
while
it
showed
no
effect
on
decreased
based
covariates.
experiment
underlines
importance
EO
transfer
extrapolation
models.
Remote Sensing,
Journal Year:
2021,
Volume and Issue:
13(3), P. 474 - 474
Published: Jan. 29, 2021
A
better
comprehension
of
soil
properties
and
processes
permits
a
progress
in
agricultural
management
effectiveness,
together
with
diminution
environmental
damage
more
beneficial
use
resources.
This
research
investigated
the
usage
multispectral
(Sentinel-2
MSI)
satellite
data
at
farm/regional
level,
for
identification
agronomic
bare
presence,
utilizing
bands
spectral
range
from
visible
to
shortwave
infrared.
The
purpose
was
assess
frequency
cloud-free
time-series
images
available
during
year
typical
areas,
needed
development
digital
mapping
(DSM)
approaches
applications,
using
hyperspectral
missions
such
as
current
PRISMA
planned
EnMAP
or
CHIME.
exploited
Google
Earth
Engine
platform,
by
processing
all
Sentinel-2
throughout
time
span
four
years.
Two
main
results
were
obtained:
(i)
frequency,
indicating
where
when
pixel
(or
an
field)
detected
surface
three
representative
areas
Italy,
(ii)
temporal
sensitivity
analysis,
providing
acquisition
useful
applicable
retrieval
variables
interest.
It
shown
that,
order
provide
effective
monitoring
capability,
revisit
five
seven
days
is
required,
which
less
than
specifications
e.g.,
CHIME
missions,
but
could
be
addressed
combining
two
sensors.
Remote Sensing,
Journal Year:
2021,
Volume and Issue:
13(17), P. 3345 - 3345
Published: Aug. 24, 2021
The
spatial
and
temporal
monitoring
of
soil
organic
carbon
(SOC),
other
properties
related
to
erosion,
is
extremely
important,
both
from
the
environmental
economic
perspectives.
Sentinel-2
(S2)
Landsat-8
(L8)
time
series
increase
probability
observe
bare
fields
in
croplands,
thus,
monitor
over
large
regions.
In
this
regard,
work
suggests
an
automated
pixel-based
approach
select
only
pure
pixels
S2
L8
series,
make
a
synthetic
image
(SBSI).
SBSIs
measured
framework
European
LUCAS
survey
were
used
calibrate
SOC,
clay,
CaCO3
prediction
models.
results
highlight
high
correlation
between
laboratory
spectra
median
spectra,
especially
for
SBSI
obtained
by
three-year
collection,
which
provides
satisfactory
terms
SOC
accuracy
(RPD:
1.74).
comparison
demonstrated
higher
capability
sensor
accuracy,
mainly
due
greater
resolution
bands
visible
region.
Whereas,
neither
nor
could
accurately
predict
clay
content.
This
because
low
spectral
their
SWIR
that
prevent
exploitation
narrow
features
these
two
attributes.
study
prove
can
estimate
croplands
using
selects
retrieves
reliable
spectra.
Geocarto International,
Journal Year:
2021,
Volume and Issue:
37(25), P. 8230 - 8253
Published: Oct. 23, 2021
Evaluation
of
spatial
variability
and
mapping
soil
properties
is
critical
for
sustainable
agricultural
production
in
arid
lands.
The
main
objectives
the
present
study
were
to
spatialize
organic
carbon
(SOC),
particle
size
distribution(clay,
sand,
silt
contents),
calcium
carbonate
equivalent
(CCE)
by
integrating
multisource
environmental
covariates,
including
digital
elevation
model
(DEM)
remote
sensing
data
machine
learning
(Cubist,
Cu
random
forest,
RF)
an
region
Iran.
Additionally,
Synthetic
Soil
Images
(SySI)
achieved
from
multi-temporal
images
bare
pixels
based
on
Landsats
4,
5,
7,
8,
a
DEM.
Three
hundred
topsoil
samples
(0–30
cm
depth)
collected
conditioned
Latin
hypercube
sampling
(cLHS)
approach
Afzar
district,
Fars
province,
southern
models
calibrated
validated
10-fold
cross-validation
approach,
performance
was
evaluated
using
root
mean
square
error
(RMSE),
ratio
interquartile
distance
(RPIQ),
coefficient
determination
(R2).
Also,
prediction
accuracy
assessed
relative
RMSE
(rRMSE).
best
RPIQ
index
showed
that
predicting
clay
(1.89)
had
good
prediction,
sand
(1.64),
SOC
(1.55),
CCE
(1.59)
fair
while
(1.13)
performed
poorly.
We
found
RF
highest
lowest
accuracies
(rRMSE
=
14.31%)
43.93%),
respectively.
discovered
combination
high-quality
RS
variables
derived
DEM
reasonably
able
predict
properties.
revealed
strong
promise
enhance
mapping,
especially
regions
with
limited
data.
Moreover,
application
can
reduce
cost
and,
accordingly,
mapping.