EarthArXiv (California Digital Library),
Journal Year:
2022,
Volume and Issue:
unknown
Published: Oct. 15, 2022
Growth
and
contraction
of
headwater
stream
networks
determine
the
extent
quality
ecologically
critical
habitat,
open
a
window
into
storage
dynamics
catchments.
A
fundamental
challenge
is
observation
process
itself:
wetted
channel
highly
dynamic
in
space
time,
with
length
sometimes
varying
by
orders
magnitude
over
course
single
storm
event
To
date,
observational
datasets
are
produced
from
boots-on-the-ground
campaigns,
drone
imaging,
or
flow
presence
sensors,
which
often
laborious
limited
their
spatial
temporal
extents.
Here,
we
evaluate
high-resolution,
multi-band
satellite
imagery
as
means
to
detect
via
machine
learning
methods
trained
using
existing
surveys.
Even
where
features
smaller
than
resolution
imagery,
absence
surface
water
may
nevertheless
be
imprinted
upon
spectral
signature
an
individual
pixel.
We
leverage
surveys
at
two
oak
savanna
catchments
northern
California
minimal
riparian
canopy
cover
due
small
subsurface
capacity
saturation
overland
flow.
train
random
forest
model
on
high-resolution
($\sim$5
m
pixel)
RapidEye
captured
contemporaneously
Withheld
test
data
indicates
prediction
accuracy
wet
vs.
dry
$>$91\%.
This
predictive
ability
used
produce
length-discharge
(L-Q)
relations
calculate
spatially
distributed
estimates
hyporheic
exchange.
sharp
break
properties
occurs
transition
main
stem
channels
lower
order
tributaries,
resulting
stepped
L-Q
relationship
that
cannot
traditionally
power
law
models.
Remotely
sensed
powerful
tool
for
producing
maps
high
($\sim$10
this
study
$>$
0.01
km$^2$
contributing
area).
Water Resources Research,
Journal Year:
2024,
Volume and Issue:
60(2)
Published: Feb. 1, 2024
Abstract
Understanding
the
spatio‐temporal
dynamics
of
runoff
generation
in
headwater
catchments
is
challenging,
due
to
intermittent
and
fragmented
nature
surface
flows.
The
active
stream
network
non‐perennial
rivers
contracts
expands,
with
a
dynamic
behavior
that
depends
on
complex
interplay
among
climate,
topography,
geology.
In
this
work,
CATchment
HYdrology,
an
integrated
surface–subsurface
hydrological
model
(ISSHM),
used
simulate
two
virtual
same,
spatially
homogeneous,
subsurface
characteristics
(hydraulic
conductivity,
porosity,
water
retention
curves)
but
different
morphology.
We
run
sets
simulations
reproduce
sequence
steady‐states
at
catchment
wetness
levels
transient
conditions
analyze
joint
variations
length
(
L
)
discharge
outlet
Q
high
resolutions.
shape
curves
differs
does
not
depend
climate
forcing,
as
it
mainly
controlled
by
underlying
topography.
then
analyzed
suitability
topographic
index
contributing
area
identify
spatial
configuration
maximum
catchments.
These
morphometric
parameters
provided
good
estimate
distribution
flowing
both
study
Our
numerical
indicate
ISSHMs
have
potential
accurately
describe
networks
processes
driving
such
that,
overall,
they
can
be
useful
tools
gain
insights
into
main
physical
drivers
streams.
Water Resources Research,
Journal Year:
2024,
Volume and Issue:
60(1)
Published: Jan. 1, 2024
Abstract
Non‐perennial
streams
have
a
global
prevalence,
but
quantitative
knowledge
of
the
temporal
dynamics
their
flowing
length—namely
extent
wet
portion
stream
network—remains
limited,
as
monitoring
spatiotemporal
configuration
channels
is
challenging
in
most
settings.
This
work
combines
high
spatial
resolution
visual
surveys
and
camera‐based
approaches
to
reconstruct
space‐time
network
3.7
km
2
Mediterranean
catchment
central
Italy.
Information
on
hydrological
status
derived
from
40
field
sub‐hourly
images
collected
with
21
stage‐cameras
are
combined
exploiting
hierarchical
principle.
The
latter
postulates
existence
Bayesian
chain,
defined
local
persistence
nodes
that
dictates
wetting/drying
order
during
expansion/retraction
cycles
network.
Our
results
highlight
complexity
study
area:
while
number
decreases
dry
season
increases
season,
persistency
exhibits
highly
heterogeneous
non‐monotonic
pattern,
originating
dynamically
disconnected
Despite
this
heterogeneity,
model
well
approximates
evolution
state
nodes,
an
accuracy
exceeds
99%.
Crucially,
allows
reconstruction
even
cases
which
part
was
not
observed.
provides
novel
conceptual
approach
for
poorly
accessible
sites.
Water Resources Research,
Journal Year:
2023,
Volume and Issue:
59(9)
Published: Aug. 16, 2023
Abstract
Growth
and
contraction
of
headwater
stream
networks
determine
habitat
extent,
open
a
window
to
the
hyporheic
zone.
A
fundamental
challenge
is
observation
this
process:
wetted
channel
extent
dynamic
in
space
time,
with
length
varying
by
orders
magnitude
over
course
single
storm
event
catchments.
To
date,
observational
data
sets
are
produced
from
boots‐on‐the‐ground
campaigns,
drone
imaging,
or
flow
presence
sensors,
which
often
laborious
limited
their
spatial
temporal
extents.
Here,
we
evaluate
satellite
imagery
as
means
detect
via
machine
learning
methods
trained
on
local
surveys
extent.
Even
where
features
smaller
than
imagery's
resolution,
surface
water
may
be
imprinted
upon
spectral
signature
an
individual
pixel.
For
two
catchments
northern
California
minimal
riparian
canopy
cover
highly
train
random
forest
model
RapidEye
captured
contemporaneously
existing
predict
(accuracy
>91%).
The
used
produce
length‐discharge
(L‐Q)
relations
calculate
spatially
distributed
estimates
capacity
exchange.
sharp
break
occurs
main
stem
channels
lower
order
tributaries,
resulting
stepped
L‐Q
relationship
that
cannot
traditionally
power
law
models.
Remotely
sensed
powerful
tool
for
mapping
at
high
resolution.
iScience,
Journal Year:
2023,
Volume and Issue:
26(8), P. 107417 - 107417
Published: July 23, 2023
The
study
of
non-perennial
streams
requires
extensive
experimental
data
on
the
temporal
evolution
surface
flow
presence
across
different
nodes
channel
networks.
However,
consistency
and
homogeneity
available
datasets
is
threatened
by
empirical
burden
required
to
map
stream
network
expansions
contractions.
Here,
we
developed
a
data-driven,
graph-theory
framework
aimed
at
representing
hierarchical
structuring
dynamics
(i.e.,
order
node
activation/deactivation
during
expansion/retraction)
through
directed
acyclic
graph.
method
enables
estimation
configuration
active
portion
based
limited
number
observed
nodes,
can
be
utilized
combine
with
resolutions
spatial
coverage.
A
proof-of-concept
application
seasonally-dry
catchment
in
central
Italy
demonstrated
ability
approach
reduce
effort
for
monitoring
efficiently
extrapolate
observations
space
time.
Hydrological Processes,
Journal Year:
2024,
Volume and Issue:
38(6)
Published: June 1, 2024
Abstract
Non‐perennial
streams
play
a
crucial
role
in
ecological
communities
and
the
hydrological
cycle.
However,
key
parameters
processes
involved
stream
intermittency
remain
poorly
understood.
While
climatic
conditions,
geology
land
use
are
well
identified,
assessment
modelling
of
groundwater
controls
on
streamflow
intermittence
challenge.
In
this
study,
we
explore
new
opportunities
to
calibrate
process‐based
3D
flow
models
designed
simulate
hydrographic
network
dynamics
groundwater‐fed
headwaters.
Streamflow
measurements
maps
considered
together
constrain
effective
hydraulic
properties
aquifer
hydrogeological
models.
The
simulations
were
then
validated
using
visual
observations
water
presence/absence,
provided
by
national
monitoring
France
(ONDE).
We
tested
methodology
two
pilot
unconfined
shallow
crystalline
catchments,
Canut
Nançon
catchments
(Brittany,
France).
found
that
both
expansion/contraction
required
simultaneously
estimate
conductivity
porosity
with
low
uncertainties.
calibration
allowed
good
prediction
intermittency,
terms
spatial
extent.
For
studied,
Nançon,
is
close
reaching
1.5
×
10
−5
m/s
4.5
m/s,
respectively.
they
differ
more
their
storage
capacity,
estimated
at
0.1%
2.2%,
Lower
capacity
leads
higher
level
fluctuations,
shorter
response
times,
an
increase
proportion
intermittent
reduction
perennial
flow.
This
framework
for
predicting
headwater
can
be
deployed
improve
our
understanding
different
geomorphological,
geological
contexts.
It
will
benefit
from
advances
remote
sensing
crowdsourcing
approaches
generate
observational
data
products
high
temporal
resolution.
Water Resources Research,
Journal Year:
2024,
Volume and Issue:
60(1)
Published: Jan. 1, 2024
Abstract
River
networks
are
not
steady
blue
lines
drawn
in
a
map,
since
they
continuously
change
their
shape
and
extent
response
to
climatic
drivers.
Therefore,
the
flowing
length
of
rivers
(
L
)
corresponding
catchment‐scale
streamflow
Q
sur
co‐evolve
dynamically.
This
paper
analyzes
relationship
between
wet
channel
river
basin,
formulating
general
analytical
model
that
includes
case
temporarily
dry
outlets.
In
particular,
framework
relaxes
common
assumption
when
discharge
at
outlet
tends
zero
upstream
approaches
zero.
Different
expressions
for
law
derived
cases
(a)
perennial
outlet;
(b)
non‐perennial
dries
out
only
whole
network
is
dry;
(c)
outlet,
experiences
surface
flow
less
time
than
other
nodes.
all
cases,
controlled
by
distribution
specific
subsurface
capacity
along
network.
For
outlets,
however,
relation
might
depend
on
an
unknown
shifting
factor.
Three
real‐world
examples
presented
demonstrate
flexibility
robustness
theory.
Our
results
indicate
be
empirically
observable
if
significant
fraction
or
some
reaches
experience
longer
gauging
station.
The
study
provides
basis
integrating
empirical
data
gathered
diverse
sites.