Ecology Letters,
Journal Year:
2020,
Volume and Issue:
23(8), P. 1189 - 1200
Published: May 21, 2020
Many
plant
water
use
models
predict
leaves
maximize
carbon
assimilation
while
minimizing
loss
via
transpiration.
Alternate
scenarios
may
occur
at
high
temperature,
including
heat
avoidance,
where
increase
to
evaporatively
cool
regardless
of
uptake;
or
failure,
non-adaptively
lose
also
uptake.
We
hypothesized
that
these
alternative
are
common
in
species
exposed
hot
environments,
with
avoidance
more
construction
cost
leaves.
Diurnal
measurements
leaf
temperature
and
gas
exchange
for
11
Sonoran
Desert
revealed
37%
increased
transpiration
the
absence
High
mass
per
area
partially
predicted
this
behaviour
(r2
=
0.39).
These
data
consistent
but
failure
is
less
likely
given
ecological
dominance
focal
species.
behaviours
not
yet
captured
any
extant
model.
Basic and Applied Ecology,
Journal Year:
2020,
Volume and Issue:
45, P. 86 - 103
Published: April 29, 2020
In
2018,
Central
Europe
experienced
one
of
the
most
severe
and
long-lasting
summer
drought
heat
wave
ever
recorded.
Before
2003
millennial
was
often
invoked
as
example
a
"hotter
drought",
classified
event
in
for
last
500
years.
First
insights
now
confirm
that
2018
climatically
more
extreme
had
greater
impact
on
forest
ecosystems
Austria,
Germany
Switzerland
than
drought.
Across
this
region,
mean
growing
season
air
temperature
from
April
to
October
3.3°C
above
long-term
average,
1.2°C
warmer
2003.
Here,
we
present
first
assessment
heatwave
European
forests.
response
event,
ecologically
economically
important
tree
species
temperate
forests
showed
signs
stress.
These
symptoms
included
exceptionally
low
foliar
water
potentials
crossing
threshold
xylem
hydraulic
failure
many
observations
widespread
leaf
discoloration
premature
shedding.
As
result
stress,
caused
unprecedented
drought-induced
mortality
throughout
region.
Moreover,
unexpectedly
strong
drought-legacy
effects
were
detected
2019.
This
implies
physiological
recovery
trees
impaired
after
leaving
them
highly
vulnerable
secondary
impacts
such
insect
or
fungal
pathogen
attacks.
consequence,
triggered
by
events
is
likely
continue
several
Our
indicates
common
are
waves
previously
thought.
occur
frequently
with
progression
climate
change,
might
approach
point
substantial
ecological
economic
transition.
also
highlights
urgent
need
pan-European
ground-based
monitoring
network
suited
track
individual
mortality,
supported
remote
sensing
products
high
spatial
temporal
resolution
track,
analyse
forecast
these
transitions.
Plants,
Journal Year:
2022,
Volume and Issue:
11(13), P. 1620 - 1620
Published: June 21, 2022
Water,
a
necessary
component
of
cell
protoplasm,
plays
an
essential
role
in
supporting
life
on
Earth;
nevertheless,
extreme
changes
climatic
conditions
limit
water
availability,
causing
numerous
issues,
such
as
the
current
water-scarce
regimes
many
regions
biome.
This
review
aims
to
collect
data
from
various
published
studies
literature
understand
and
critically
analyze
plants’
morphological,
growth,
yield,
physio-biochemical
responses
drought
stress
their
potential
modulate
nullify
damaging
effects
via
activating
natural
physiological
biochemical
mechanisms.
In
addition,
described
breakthroughs
understanding
how
plant
hormones
influence
phytohormonal
interaction
through
signaling
under
regimes.
The
information
for
this
was
systematically
gathered
different
global
search
engines
scientific
databases
Science
Direct,
including
Google
Scholar,
Web
Science,
related
studies,
books,
articles.
Drought
is
significant
obstacle
meeting
food
demand
world’s
constantly
growing
population.
Plants
cope
with
cellular
osmotic
potential,
activation
defense
systems
form
antioxidant
enzymes
accumulation
osmolytes
proteins,
proline,
glycine
betaine,
phenolic
compounds,
soluble
sugars.
Phytohormones
developmental
processes
networks,
which
aid
acclimating
plants
biotic
abiotic
challenges
and,
consequently,
survival.
Significant
progress
has
been
made
jasmonates,
salicylic
acid,
ethylene
identifying
important
components
roles
stress.
Other
hormones,
abscisic
auxin,
gibberellic
brassinosteroids,
peptide
have
linked
pathways
ways.
Nature Communications,
Journal Year:
2022,
Volume and Issue:
13(1)
Published: Aug. 19, 2022
Water
availability
plays
a
critical
role
in
shaping
terrestrial
ecosystems,
particularly
low-
and
mid-latitude
regions.
The
sensitivity
of
vegetation
growth
to
precipitation
strongly
regulates
global
dynamics
their
responses
drought,
yet
changes
response
climate
change
remain
poorly
understood.
Here
we
use
long-term
satellite
observations
combined
with
dynamic
statistical
learning
approach
examine
the
greenness
over
past
four
decades.
We
observe
robust
increase
(0.624%
yr−1)
for
drylands,
decrease
(−0.618%
wet
Using
model
simulations,
show
that
contrasting
trends
between
dry
regions
are
caused
by
elevated
atmospheric
CO2
(eCO2).
eCO2
universally
decreases
reducing
leaf-level
transpiration,
However,
this
transpiration
reduction
is
overridden
at
canopy
scale
large
proportional
leaf
area.
increased
drylands
implies
potential
ecosystem
stability
greater
impacts
droughts
these
vulnerable
ecosystems
under
continued
change.
Changes
may
be
hydroclimate
dependent.
authors
reveal
vs.
wetter
last
4
decades
identify
as
major
contributing
factor.
Urban forestry & urban greening,
Journal Year:
2020,
Volume and Issue:
58, P. 126970 - 126970
Published: Dec. 28, 2020
Increasing
urban
tree
cover
is
an
often
proposed
mitigation
strategy
against
heat
as
trees
are
expected
to
cool
cities
through
evapotranspiration
and
shade
provision.
However,
also
modify
wind
flow
aerodynamic
roughness,
which
can
potentially
limit
dissipation.
Existing
studies
show
a
varying
cooling
potential
of
in
different
climates
times
the
day.
These
differences
so
far
not
systematically
explained
partitioning
individual
effects
challenging
impossible
observations
alone.
Here,
we
conduct
numerical
experiments
removing
adding
radiation,
evapotranspiration,
roughness
caused
by
using
mechanistic
ecohydrological
model.
Simulations
presented
for
four
(Phoenix,
Singapore,
Melbourne,
Zurich)
considering
seasonal
diurnal
cycles
air
surface
temperatures.
Results
that
well-watered
alone
decrease
local
2
m
temperature
at
maximum
3.1–
5.8
°C
during
summer.
Further
prevented
stomatal
closure
peak
temperatures
high
vapour
pressure
deficits
transpiration.
While
shading
reduces
temperatures,
interaction
non-transpiring
with
radiation
increase
up
1.6
–
2.1
certain
hours
day
scale,
thus
partially
counteracting
evapotranspirative
effect.
Furthermore,
analysed
scenarios,
do
account
blockage
effects,
lead
inhibits
turbulent
energy
exchange
increases
daytime.
At
night,
single
variable
likely
due
atmospheric
stability
within
canyon.
results
explain
reported
diurnal,
climatic
trees,
guide
future
field
campaigns,
planning
strategies,
species
selection
aimed
improving
microclimate
greenery.
Nature Communications,
Journal Year:
2019,
Volume and Issue:
10(1)
Published: July 30, 2019
Stomata,
the
microvalves
on
leaf
surfaces,
exert
major
influences
across
scales,
from
plant
growth
and
productivity
to
global
carbon
water
cycling.
Stomatal
opening
enables
photosynthesis,
use,
whereas
survival
of
drought
depends
stomatal
closure.
Here
we
report
that
function
is
constrained
by
a
safety-efficiency
trade-off,
such
species
with
greater
conductance
under
high
availability
(gmax)
show
sensitivity
closure
during
dehydration,
i.e.,
higher
potential
at
which
reduced
50%
(Ψgs50).
The
gmax
-
Ψgs50
trade-off
its
mechanistic
basis
supported
experiments
leaves
California
woody
species,
in
analyses
previous
studies
responses
diverse
flowering
around
world.
Linking
two
fundamental
key
roles
stomata-the
enabling
gas
exchange,
first
defense
against
drought-this
constrains
rates
use
leaves,
impacts
ecosystems.
New Phytologist,
Journal Year:
2019,
Volume and Issue:
225(1), P. 126 - 134
Published: Sept. 9, 2019
Summary
Efficient
water
transport
from
soil
to
leaves
sustains
stomatal
opening
and
steady‐state
photosynthesis.
The
aboveground
portion
of
this
pathway
is
well‐described,
yet
the
roots
their
connection
with
are
still
poorly
understood
due
technical
limitations.
Here
we
used
a
novel
rehydration
technique
investigate
changes
in
hydraulic
between
within
plant
body
as
individual
olive
plants
were
subjected
range
stresses.
Whole
root
resistance
(including
radial
xylem
soil–root
interface)
constituted
81%
whole‐plant
unstressed
plants,
increasing
>
95%
under
moderate
level
stress.
decline
whole
conductance
occurred
parallel
closure
contributed
significantly
reduction
canopy
according
model.
Our
results
demonstrate
that
losses
conductance,
mainly
disconnection
during
stress
profound
sufficient
induce
before
cavitation
occurs.
Future
studies
will
determine
whether
core
regulatory
role
hydraulics
exists
more
generally
among
diverse
species.
New Phytologist,
Journal Year:
2021,
Volume and Issue:
231(1), P. 32 - 39
Published: March 17, 2021
With
climate
change,
heat
waves
are
becoming
increasingly
frequent,
intense
and
broader
in
spatial
extent.
However,
while
the
lethal
effects
of
on
humans
well
documented,
impacts
flora
less
understood,
perhaps
except
for
crops.
We
summarize
recent
findings
related
to
wave
including:
sublethal
at
leaf
plant
scales,
secondary
ecosystem
effects,
more
complex
such
as
increased
frequency
across
all
seasons,
interactions
with
other
disturbances.
propose
generalizable
practical
trials
quantify
critical
bounding
conditions
vulnerability
waves.
Collectively,
vulnerabilities
appear
be
underappreciated
understudied,
particularly
respect
understanding
driven
die-off
tipping
points.
Proceedings of the National Academy of Sciences,
Journal Year:
2021,
Volume and Issue:
118(16)
Published: April 12, 2021
Understanding
the
vulnerability
of
trees
to
drought-induced
mortality
is
key
predicting
fate
forests
in
a
future
climate
with
more
frequent
and
intense
droughts,
although
underlying
mechanisms
are
difficult
study
adult
trees.
Here,
we
explored
dynamic
changes
water
relations
limits
hydraulic
function
dying
adults
Norway
spruce
(Picea
abies
L.)
during
progression
record-breaking
2018
Central
European
drought.
In
on
trajectory
mortality,
observed
rapid,
nonlinear
declines
xylem
pressure
that
commenced
at
early
onset
cavitation
caused
complete
loss
conductance
within
very
short
time.
We
also
severe
depletions
nonstructural
carbohydrates,
though
carbon
starvation
could
be
ruled
out
as
cause
tree
death,
both
surviving
showed
these
metabolic
limitations.
Our
observations
provide
striking
field-based
evidence
for
fast
dehydration
collapse
spruce.
The
decline
suggests
considering
temporal
dynamics
critical
death.
system
time
demonstrates
can
rapidly
pushed
zone
safety
summary,
our
findings
point
toward
higher
risk
than
previously
assumed,
which
line
current
reports
unprecedented
levels
this
major
species.
Nature Communications,
Journal Year:
2022,
Volume and Issue:
13(1)
Published: Jan. 10, 2022
Abstract
Heatwaves
exert
disproportionately
strong
and
sometimes
irreversible
impacts
on
forest
ecosystems.
These
remain
poorly
understood
at
the
tree
species
level
across
large
spatial
scales.
Here,
we
investigate
effects
of
record-breaking
2018
European
heatwave
growth
water
status
using
a
collection
high-temporal
resolution
dendrometer
data
from
21
53
sites.
Relative
to
two
preceding
years,
annual
stem
was
not
consistently
reduced
by
but
stems
experienced
twice
temporary
shrinkage
due
depletion
reserves.
Conifer
were
less
capable
rehydrating
overnight
than
broadleaves
gradients
soil
atmospheric
drought,
suggesting
resilience
toward
transient
stress.
In
particular,
Norway
spruce
Scots
pine
extensive
dehydration.
Our
high-resolution
network
suitable
disentangle
severe
desiccation
large-spatial
scales
in
situ,
provided
insights
which
may
be
more
vulnerable
climate
extremes.