Abstract.
We
present
the
first
direct
measurements
of
NO3
reactivity
(or
inverse
lifetime,
s−1)
in
Finnish
boreal
forest.
The
data
were
obtained
during
IBAIRN
campaign
(Influence
Biosphere-Atmosphere
Interactions
on
Reactive
Nitrogen
budget)
which
took
place
Hyytiälä,
Finland
summer/autumn
transition
September
2016.
was
generally
very
high
with
a
maximum
value
0.94
s−1
and
displayed
strong
diel
variation
campaign-averaged
nighttime
mean
0.11
compared
to
daytime
0.04
s−1.
highest
NO3-reactivity
accompanied
by
major
depletion
canopy
level
ozone
associated
temperature
inversions
levels
monoterpenes.
sufficiently
large
that
reactions
organic
trace
gases
could
compete
photolysis
reaction
NO.
There
no
significant
reduction
measured
between
beginning
end
indicating
any
seasonal
emissions
reactive
biogenic
offset
from
forest
floor.
Observations
hydrocarbons
(BVOC)
suggested
dominant
role
for
monoterpenes
determining
reactivity.
Reactivity
not
accounted
in-situ
measurement
NO
BVOCs
variable
across
cycle
with,
average,
circa
30
%
“missing”
60
missing
day.
Measurement
at
various
heights
(8.5
25
m)
both
above
below
canopy,
revealed
nighttime,
vertical
gradient
values
closest
ground.
disappeared
due
efficient
mixing.
Journal of Ecology,
Год журнала:
2024,
Номер
112(6), С. 1210 - 1224
Опубликована: Апрель 1, 2024
Abstract
Here
we
address
the
combined
impact
of
multiple
stressors
that
are
becoming
more
common
with
climate
change.
To
study
effects
a
lower
water
table
(WT)
and
increased
frequency
drought
periods
on
resistance
resilience
peatlands,
conducted
mesocosm
experiment.
This
evaluated
how
photosynthesis
lawn
Sphagnum
mosses
responds
to
recovers
from
an
experimental
periodic
after
exposure
stresses
deep
or
deepened
WT
(naturally
dry
17‐year‐long
level
drawdown
[WLD]
in
fen
bog
environments).
We
aimed
quantify
if
WTs
(1)
support
acclimation
drought,
(2)
increase
base‐level
physiological
stress
(3)
exacerbate
drought.
There
was
no
evidence
drier
environments;
decreased
all
species
studied.
WLDdecreased
bog‐originating
prior
indicating
these
were
stressed
by
hydrological
Deep
exacerbated
vulnerability
combination
drying
habitats
increasing
could
lead
rapid
transition
vegetation.
Water‐retaining
traits
may
Large
capitula
size
associated
higher
resistance;
originating
studied
here
lacked
large
dense
carpet
structure
vulnerable
than
larger
species.
Consequently,
lawns
bogs
become
threatened.
Recovery
rewetting
significant
for
mosses,
but
none
completely
recovered
within
3
weeks.
The
most
drought‐resilient
had
origin,
fens
less
likely
undergo
sudden
due
S
ynthesis
:
Water
change
increases
sensitivity
moves
them
closer
their
tipping
point
as
edge
ecological
envelope
rapidly
shut
down
recover
poorly.
Restoration Ecology,
Год журнала:
2024,
Номер
32(7)
Опубликована: Июнь 24, 2024
Peatland
restoration
is
seen
as
a
key
nature‐based
solution
to
tackle
climate
change
and
biodiversity
loss.
In
Europe,
nearly
50%
of
peatlands
have
been
drained
during
the
last
decades,
which
shifted
their
soils
carbon
dioxide
(CO
2
)
sources.
Soils
forestry‐drained
are
known
vary
from
CO
sources
small
sinks
depending
on
fertility
wetness.
When
restored,
it
can
be
expected
that
rates
methane
exchange
will
site
We
generated
seven
pathways
with
different
starting
end
points
assessed
impacts
them.
The
GHG
emission
coefficients
were
compiled
literature,
radiative
forcing
was
calculated
for
500‐year
time
period
since
restoration.
All
improved
sink
capacity;
however,
impact
differed
cooling
warming.
highest
occurred
in
pathway
leading
nutrient‐rich
toward
tree‐covered
spruce
or
pine
mires.
Warming
nutrient‐poor
open
peatlands.
results
this
study
used
help
identify
peatland
sites
targets
maximize
mitigation
practice,
has
fulfill
other
targets,
such
safeguarding,
improvement
hydrological
conditions,
socio‐economic
aspects.
Fulfilling
all
simultaneously
requires
compromises
targets.
Boreas,
Год журнала:
2024,
Номер
53(2), С. 282 - 295
Опубликована: Фев. 2, 2024
Northern
fens,
that
host
unique
biota
and
form
a
remarkable
carbon
stock,
are
sensitive
to
changes
in
the
moisture
balance
and,
therefore,
may
be
strongly
affected
by
climatic
fluctuations.
However,
long‐term
monitoring
palaeoecological
studies
of
fens
relatively
rare
as
result,
their
responses
past
current
fluctuations
poorly
known.
In
this
study,
we
examined
recent
vegetation
change
well
testate
amoeba
communities
mire
margin
subarctic
fen
Finnish
Lapland
with
four
peat
profiles.
Testate
amoebae
were
used
indicators
water
table
depth.
The
showed
drastic
shift
from
sedge‐dominated
Sphagnum
‐dominated
during
late
20th
early
21st
centuries.
This
was
accompanied
turnover
community.
amoeba‐based
reconstructions
indicated
drying.
due
lowering
either
accelerated
increment
or
enhanced
evaporation.
observed
hummock
establishment
concurs
documented
hemisphere‐wide
expansion
trend
fens.
strengthen
sink
storage
capacity
these
peatlands,
which
could
viewed
welcome
negative
feedback
process
ongoing
climate
warming.
also
poses
threat
biodiversity
since
not
only
species‐rich
habitats
but
endangered
ecosystems.
Water,
Год журнала:
2024,
Номер
16(7), С. 985 - 985
Опубликована: Март 28, 2024
Peatlands
store
large
amounts
of
carbon
in
wetland
ecosystems.
The
hydrological
conditions
within
peatlands
are
important
factors
that
affect
the
biochemical
cycle
and
patterns
greenhouse
gas
emissions
these
peatlands.
This
study
was
carried
out
Changbai
Mountain
Jinchuan
peatland
to
investigate
variations
dioxide
methane
peat
swamps
have
undergone
distinct
saturation
conditions.
Three
types
(high
water
levels
(S1);
medium
(S2);
low
(S3))
at
different
flood
depths
were
selected
as
specific
sampling
points.
static
box
chromatography
methods
used
time
periods
(6:00;
12:00;
18:00)
from
July
September.
discharge
flux
CO2
CH4
slowly
increased
with
increase
level.
results
indicate
similarity
fluctuation
trends
between
fluxes
S1
S2
fluctuations
levels.
During
entire
growth
season,
range
−695.329~859.907
mg
m2h−1
259.981~147.155
m2h−1,
respectively.
Furthermore,
there
variation
mutation
characteristics
two
gases,
exhibited
larger
(−7.08~3.40)
than
(−1.79~1.26).
In
terms
daily
changes,
showed
an
upward
trend,
while
had
a
downward
trend.
These
tend
subsequent
effects
on
climate
change.
highlights
potential
theoretical
support
reduce
anthropogenic
activities
can
be
achieved
by
undertaking
measures
conserve
explore
mitigation
minimize
hence
impacts
Assessing
how
dominant
peatland
species,
such
as
Dasiphora
fruticosa,
adapt
to
water
table
decline
is
crucial
advance
understanding
of
their
growth
and
survival
strategies.
Currently,
most
studies
have
primarily
focused
on
biomass,
with
limited
knowledge
the
response
non-structural
carbohydrates
(NSCs)
physiological
adaptations
these
woody
plants
under
long-term
drainage.
This
study
assessed
photosynthesis
transpiration
rates,
NSC
concentrations
(including
soluble
sugars
starch)
in
leaves,
stems,
roots
D.
fruticosa
drainage
a
minerotrophic
peatland.
The
aim
was
elucidate
plant
adaptation
mechanisms
decline.
effectively
regulated
carbon
(C)
demand
supply
by
significantly
enhancing
photosynthesis,
transpiration,
biomass
accumulation,
thereby
maintaining
stable
C
storage
declined.
There
notable
reduction
sugar
concentration
leaves
increasing
decline,
while
starch
all
three
organs
remained
relatively
constant.
Although
consistently
higher
than
that
relative
proportion
gradually
decreased
increased
stems
Our
findings
reveal
reduces
acclimation
might
impact
dynamics
peatlands.
Understanding
vital
for
predicting
sequestration
emission
ecosystems
changing
environmental
conditions.
Dissertationes Forestales,
Год журнала:
2024,
Номер
2024
Опубликована: Янв. 1, 2024
Boreal
peatlands
harbour
large
stores
of
carbon
as
peat
below
their
surfaces.
Climate
change
is
expected
to
cause
drying
in
northern
peatlands,
which
will
turn
impact
the
balance
these
ecosystems
that
maintained
by
high
water
tables
and
hydrologically
sensitive
plants
growing
there.
This
study
aims
quantify
how
vegetation
be
structured
(I)
photosynthesize
(II,
III)
a
future
climate
emulated
long-term
level
drawdown
(WLD).
To
do
this,
changes
its
photosynthesis
after
WLD
are
linked,
response
Sphagnum
mosses
periodic
drought
investigated.
Field
measurements
were
done
at
field
experiment
contained
rich
(mesotrophic)
fen,
poor
(oligotrophic)
fen
bog
(ombrotrophic)
site.
Measurements
included
surveys
from
existing
permanent
sample
plots
leaf-level
dioxide
exchange
measurements.
For
an
controlled
conditions
peatland
surface
cores
this
transported
greenhouse
where
lawn
Sphagna
during
experimental
was
measured.
The
revealed
depend
on
type.
species
composition
most
impacted
WLD,
while
demonstrated
stability.
Similarly,
increases
occurred
following
vascular
plant-covered
negligible
Sphagnum-carpeted
bog.
two
fens
shifted
open
sedge-,
or
sedge
Sphagnum-dominated
ecosystem,
tree-dominated
ecosystem.
Canopy
development
further
accelerated
shading
sheltering
understorey
vegetation.
Vascular
likely
increase
productivity
they
best
suited
utilize
nutrients
made
available
mineralization,
moss
little.
exposed
more
vulnerable
compared
those
wet
sites.
Large
capitula
typical
appeared
beneficial
for
surviving
drought.
work
have
photosynthetic
function
ecosystems,
particular.
better
predict
feedbacks
changes,
dynamics
including
should
updated
global
process
models.
Future
research
understand
tipping
point
different
types
climatic
regions
help
us
diverse
globally
important
systems.
