Agronomy,
Год журнала:
2024,
Номер
14(9), С. 2067 - 2067
Опубликована: Сен. 10, 2024
The
spatiotemporal
continuity
characteristics
of
drought
are
the
basis
for
analyzing
its
spatial
migration
and
evolution,
which
is
significant
mitigation
early
warning
drought.
aim
this
paper
to
identify
meteorological
vegetation
events
in
China
from
1982
2022,
reveal
dynamic
changes
typical
events,
elucidate
propagation
results
showed
that
(1)
based
on
a
three-dimensional
clustering
algorithm,
experienced
138
76
events;
(2)
severity
event
No.
M138
(2022.03–2022.11)
reached
667.58
×
104
km2·month,
V68
(2019.06–2020.04)
572.89
km2·month;
(3)
total
40
meteorological-vegetation
pairs
had
been
identified,
was
divided
into
three
main
types:
“single”,
“simple”,
“complexity”;
(4)
pair
P-34,
area
difference
16.45
km2,
3.89
km2.
research
can
provide
new
perspective
identifying
perspective,
great
significance
predicting
protecting
ecological
environment.
Agricultural Water Management,
Год журнала:
2024,
Номер
296, С. 108807 - 108807
Опубликована: Апрель 2, 2024
The
reference
evapotranspiration
(ETo)
is
a
key
parameter
in
achieving
sustainable
use
of
agricultural
water
resources.
To
accurately
acquire
ETo
under
limited
conditions,
this
study
combined
the
northern
goshawk
optimization
algorithm
(NGO)
with
extreme
gradient
boosting
(XGBoost)
model
to
propose
novel
NGO-XGBoost
model.
performance
was
evaluated
using
meteorological
data
from
30
stations
North
China
Plain
and
compared
XGBoost,
random
forest
(RF),
k
nearest
neighbor
(KNN)
models.
An
ensemble
embedded
feature
selection
(EEFS)
method
results
RF,
adaptive
(AdaBoost),
categorical
(CatBoost)
models
used
obtain
importance
factors
estimating
ETo,
thereby
determine
optimal
combination
inputs
indicated
that
by
top
3,
4,
5
important
as
input
combinations,
all
achieved
high
estimation
accuracy.
It
worth
noting
there
were
significant
spatial
differences
precisions
four
models,
but
exhibited
consistently
precisions,
global
indicator
(GPI)
rankings
1st,
range
coefficient
determination
(R2),
nash
efficiency
(NSE),
root
mean
square
error
(RMSE),
absolute
(MAE)
bias
(MBE)
0.920–0.998,
0.902–0.998,
0.078–0.623
mm
d−1,
0.058–0.430
−0.254–0.062
respectively.
Furthermore,
accuracy
varied
across
different
seasons,
which
more
significantly
affected
humidity
wind
speed
winter.
When
target
station
insufficient,
trained
historical
neighboring
still
maintained
precision.
Overall,
recommends
reliable
for
provides
calculating
absence
data.
International Journal of Applied Earth Observation and Geoinformation,
Год журнала:
2024,
Номер
129, С. 103822 - 103822
Опубликована: Апрель 7, 2024
Vegetation
Condition
Index
(VCI),
as
a
widely
used
drought
index
for
monitoring
vegetation
stress
and
estimating
trends,
is
constructed
by
normalizing
the
long-term
satellite-based
Normalized
Difference
(NDVI)
data.
However,
under
global
greening,
across
different
regions
has
shown
an
increasing
trend
in
greenness,
which
may
cause
VCI
to
inherit
greening
NDVI
further
hamper
its
ability
analysis.
Therefore,
this
study
quantitatively
explored
underlying
relationship
among
VCI,
from
2001
2021
examine
utility
of
changing
environment.
Multi-source
indicators
were
employed
surrogates
greenness
drought,
respectively.
Particularly,
Leaf
Area
(LAI)
Net
Primary
Production
(NPP)
proxies
while
Root-Zone
Soil
Moisture
(RZSM),
Palmer
Drought
Severity
(PDSI),
Standardized
Precipitation-Evapotranspiration
(SPEI)
indices.
Based
on
Sen's
slope
estimator,
Mann-Kendall
(MK)
test,
partial
correlation
analysis,
our
results
show
that
proportion
pixels
with
approximately
38.5%,
similar
greenness-related
indices
(i.e.,
NPP
[26.47%]
LAI
[59.14%]),
significantly
higher
than
other
RZSM
[19.83%],
PDSI
[10.38%],
SPEI
[9.32%]).
Furthermore,
demonstrate
index,
exhibits
closer
(LAI
NPP)
(RZSM,
PDSI,
SPEI).
These
reveal
potential
limitations
practical
applications
could
enhance
understanding
dynamics
especially
current
globe.
Additionally,
serves
cautionary
note
scientific
community
involved
monitoring,
emphasizing
not
be
suitable
tool
evaluating
trends
impacts
vegetation.
Plants,
Год журнала:
2023,
Номер
12(13), С. 2456 - 2456
Опубликована: Июнь 26, 2023
This
study
aims
to
explore
the
impacts
of
exogenous
sorbitol
on
maize
seedlings
under
polyethylene
glycol
(PEG)-simulated
drought
stress.
Six
treatments
were
set:
normal
condition
(CK),
PEG
(P),
10
mM
(10S),
plus
(10SP),
100
(100S)
and
(100SP).
Maize
seedlings'
growth
PEG-simulated
stress
was
significantly
inhibited
largely
alleviated
this
inhibition.
The
10SP
treatment
grew
much
better
than
those
P,
100S
100SP
no
significant
difference
in
parameters
observed
between
control
10S
treatment.
treated
with
had
higher
contents
soluble
sugar,
protein,
proline,
ascorbic
acid
(AsA),
reduced
glutathione
(GSH),
relative
water
content,
activities
antioxidant
enzymes
aldose
reductase,
but
lower
malondialdehyde
(MDA),
H2O2
electrical
conductivity
100SP.
qRT-PCR
analysis
showed
that
transcript
levels
genes
encoding
putative
reductase
(AR)
P
up-regulated
sorbitol-applied
treatments.
Taken
together,
results
demonstrated
application
conferred
tolerance
by
up-regulating
expression
AR-related
enhance
accumulation
intracellular
osmotic
substances
such
as
improve
systems
tone
down
damage
caused
Ecological Indicators,
Год журнала:
2023,
Номер
156, С. 111102 - 111102
Опубликована: Окт. 20, 2023
Drought
caused
by
global
warming
has
a
profound
impact
on
the
stability
of
terrestrial
ecosystems
and
agricultural
production.
As
one
key
indicators
to
measure
response
climate
change,
spatial
difference
ecosystem
resilience
will
also
affect
accuracy
regional
drought
risk
assessment.
In
this
study,
12-month
standardized
precipitation
evapotranspiration
index
(SPEI-12)
was
used
identify
characteristics
combined
with
meteorological
elements
characterize
hazard.
vulnerability
characterized
using
crop
environmental
sensitivity,
disaster
prevention,
mitigation
capacity.
Specifically,
considered
in
assessing
vulnerability.
And
exposure
investigated
considering
sown
area
population
density.
Based
this,
assessment
framework
constructed
random
forest
algorithm
applied
Huang-Huai-Hai
(HHH)
Plain,
China.
The
results
showed
that:
(1)
approximately
66.34
%
HHH
Plain
had
hazard
level
above
moderate;
among
them,
southern
Hebei,
northern
Anhui,
Henan,
scattered
small
areas
Shandong
were
extreme
high
areas.
(2)
northeast
central
Shandong,
Jiangsu
areas,
accounting
for
10.34%
total
area.
(3)
low
south
north,
center.
Among
these,
border
regions
part
Jiangsu,
as
well
Henan
high,
11.23%.
(4)
more
suitable
Plain.
This
study
result
could
provide
scientific
reference
managing
water
resources
preventing
drought.
