Paleobiology,
Год журнала:
2018,
Номер
44(4), С. 575 - 602
Опубликована: Авг. 16, 2018
Abstract
Estimating
the
effects
and
timing
of
anthropogenic
impacts
on
composition
macrobenthic
communities
is
challenging,
because
early
twentieth-century
surveys
are
sparse
corresponding
intervals
in
sedimentary
sequences
mixed
by
bioturbation.
Here,
to
assess
eutrophication
northern
Adriatic
Sea,
we
account
for
mixing
with
dating
bivalve
Corbula
gibba
at
two
stations
high
accumulation
(Po
prodelta)
one
station
moderate
(Isonzo
prodelta).
We
find
that,
first,
pervasively
bioturbated
muds
typical
highstand
conditions
deposited
twentieth
century
were
replaced
relicts
flood
layers
content
total
organic
carbon
(TOC)
late
Po
prodelta.
The
shelly
Isonzo
prodelta
amalgamated
but
also
show
an
upward
increase
TOC.
Second,
C.
shells
shows
that
shift
from
characterized
a
decrease
stratigraphic
disorder
temporal
resolution
assemblages
~25–50
years
~10–20
both
regions.
This
reflects
decline
depth
fully
layer
more
than
20
cm
few
centimeters.
Third,
abundance
opportunistic
species
loss
formerly
abundant,
hypoxia-sensitive
coincided
bioturbation,
higher
preservation
matter,
frequency
seasonal
hypoxia
depositional
ecosystem
regime
occurred
ca.
a.d.
1950.
Therefore,
enhanced
food
supply
overwhelmed
oxygen
depletion,
even
when
hypoxic
limited
weeks
per
year
Sea.
Preservation
trends
molluscan
events
cores
was
reduced
bioturbation
century.
Increasingly,
ecological
modellers
are
integrating
paleodata
with
future
projections
to
understand
climate-driven
biodiversity
dynamics
from
the
past
through
current
century.
Climate
simulations
earth
system
models
necessary
this
effort,
but
must
be
debiased
and
downscaled
before
they
can
used
by
models.
Downscaling
methods
observational
baselines
vary
among
researchers,
which
produces
confounding
biases
climate
simulations.
We
present
unified
datasets
of
for
North
America
21
ka
BP
2100AD,
at
0.5°
spatial
resolution.
Temporal
resolution
is
decadal
averages
monthly
data
until
1950AD,
average
climates
1950-2005
AD,
2010
also
provided.
This
downscaling
includes
two
transient
paleoclimatic
12
IPCC
AR5
(CMIP5)
historical
(1850-2005),
RCP4.5,
RCP8.5
21st-century
scenarios.
variables
include
primary
derived
bioclimatic
variables.
These
provide
a
common
set
suitable
seamlessly
modelling
effects
change
on
species
distributions
diversity.
Proceedings of the National Academy of Sciences,
Год журнала:
2019,
Номер
116(44), С. 22106 - 22114
Опубликована: Окт. 14, 2019
Significance
Climate
change,
habitat
loss,
and
overharvesting
are
threatening
coastal
ecosystems
worldwide.
A
less
widely
recognized
threat
is
the
decline
in
Indigenous
mariculture
practices.
These
practices,
such
as
building
of
clam
gardens,
structured
for
millennia.
Teasing
out
dynamic
intertwined
relationships
between
humans
culturally
valued
species,
clams,
requires
long-term
paleoecological
archaeological
records.
records
requisite
creating
meaningful
management
targets
applying
traditional
tending
to
increase
productivity
sustainability
our
foods
today.
Documenting
these
interactions
ecosystems,
we
have
done
here,
also
counteracts
erasure
connections
peoples
their
lands
seas.
Proceedings of the National Academy of Sciences,
Год журнала:
2016,
Номер
113(51), С. 14552 - 14559
Опубликована: Дек. 12, 2016
Endangered
forest–grassland
mosaics
interspersed
with
expanding
agriculture
and
silviculture
occur
across
many
parts
of
the
world,
including
southern
Brazilian
highlands.
This
natural
mosaic
ecosystem
is
thought
to
reflect
alternative
stable
states
driven
by
threshold
responses
recruitment
fire
moisture
regimes.
The
role
adaptive
human
behavior
in
such
systems
remains
understudied,
despite
its
pervasiveness
fact
that
ecosystems
can
exhibit
complex
dynamics.
We
develop
a
nonlinear
mathematical
model
coupled
human–environment
dynamics
social
processes
regarding
conservation
economic
land
valuation.
Our
objective
better
understand
how
respond
changes
ecological
conditions.
parameterized
data
on
ecology,
land-use
profits,
questionnaire
results
concerning
landowner
preferences
values.
find
presently
resides
at
crucial
juncture
where
relatively
small
conditions
generate
wide
variety
possible
outcomes,
complete
loss
mosaics;
large-amplitude,
long-term
oscillations
between
preclude
stability;
even
exclusion
agriculture/silviculture.
In
general,
increasing
time
horizon
used
for
decision
making
more
likely
maintain
stability.
contrast,
inherent
value
either
forests
or
grasslands
induce
large
oscillations—especially
forests—due
feedback
from
rarity-based
decisions.
Given
potential
dynamics,
empirically
grounded
dynamical
models
should
play
larger
policy
formulation
ecosystems.
Paleobiology,
Год журнала:
2018,
Номер
44(4), С. 575 - 602
Опубликована: Авг. 16, 2018
Abstract
Estimating
the
effects
and
timing
of
anthropogenic
impacts
on
composition
macrobenthic
communities
is
challenging,
because
early
twentieth-century
surveys
are
sparse
corresponding
intervals
in
sedimentary
sequences
mixed
by
bioturbation.
Here,
to
assess
eutrophication
northern
Adriatic
Sea,
we
account
for
mixing
with
dating
bivalve
Corbula
gibba
at
two
stations
high
accumulation
(Po
prodelta)
one
station
moderate
(Isonzo
prodelta).
We
find
that,
first,
pervasively
bioturbated
muds
typical
highstand
conditions
deposited
twentieth
century
were
replaced
relicts
flood
layers
content
total
organic
carbon
(TOC)
late
Po
prodelta.
The
shelly
Isonzo
prodelta
amalgamated
but
also
show
an
upward
increase
TOC.
Second,
C.
shells
shows
that
shift
from
characterized
a
decrease
stratigraphic
disorder
temporal
resolution
assemblages
~25–50
years
~10–20
both
regions.
This
reflects
decline
depth
fully
layer
more
than
20
cm
few
centimeters.
Third,
abundance
opportunistic
species
loss
formerly
abundant,
hypoxia-sensitive
coincided
bioturbation,
higher
preservation
matter,
frequency
seasonal
hypoxia
depositional
ecosystem
regime
occurred
ca.
a.d.
1950.
Therefore,
enhanced
food
supply
overwhelmed
oxygen
depletion,
even
when
hypoxic
limited
weeks
per
year
Sea.
Preservation
trends
molluscan
events
cores
was
reduced
bioturbation
century.