Abstract
Processes
that
drive
variability
in
catchment
solute
sourcing,
transformation,
and
transport
can
be
investigated
using
concentration–discharge
(C–Q)
relationships.
These
relationships
reflect
in‐stream
processes
operating
across
nested
temporal
scales,
incorporating
both
short
long‐term
patterns.
Scientists
therefore
leverage
catchment‐scale
C–Q
datasets
to
identify
distinguish
among
the
underlying
meteorological,
biological,
geological
export
patterns
from
catchments
influence
shape
of
their
respective
We
have
synthesized
current
knowledge
regarding
geological,
meteorological
on
for
various
types
diel
decadal
time
scales.
cross‐scale
linkages
tools
researchers
use
explore
these
interactions
Finally,
we
gaps
our
understanding
dynamics
as
reflections
processes.
also
lay
foundation
developing
an
integrated
approach
investigate
relationships,
reflecting
biogeochemical
effects
environmental
change
water
quality.
This
article
is
categorized
under:
Science
Water
>
Hydrological
Quality
Environmental
Change
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(4), P. 2357 - 2368
Published: Feb. 3, 2021
Dissolved
oxygen
(DO)
reflects
river
metabolic
pulses
and
is
an
essential
water
quality
measure.
Our
capabilities
of
forecasting
DO
however
remain
elusive.
Water
data,
specifically
data
here,
often
have
large
gaps
sparse
areal
temporal
coverage.
Earth
surface
hydrometeorology
on
the
other
hand,
become
largely
available.
Here
we
ask:
can
a
Long
Short-Term
Memory
(LSTM)
model
learn
about
dynamics
from
intensive
(daily)
data?
We
used
CAMELS-chem,
new
set
with
concentrations
236
minimally
disturbed
watersheds
across
U.S.
The
generally
learns
theory
solubility
captures
its
decreasing
trend
increasing
temperature.
It
exhibits
potential
predicting
in
"chemically
ungauged
basins",
defined
as
basins
without
any
measurements
broadly
general.
misses
some
peaks
troughs
when
in-stream
biogeochemical
processes
important.
Surprisingly,
does
not
perform
better
where
more
are
Instead,
it
performs
low
variations
streamflow
DO,
high
runoff-ratio
(>0.45),
winter
precipitation
peaks.
Results
here
suggest
that
collections
at
sparsely
monitored
areas
to
overcome
issue
scarcity,
outstanding
challenge
community.
Nature Communications,
Journal Year:
2021,
Volume and Issue:
12(1)
Published: March 4, 2021
Abstract
Groundwater
discharge
generates
streamflow
and
influences
stream
thermal
regimes.
However,
the
water
quality
buffering
capacity
of
groundwater
depends
on
aquifer
source-depth.
Here,
we
pair
multi-year
air
temperature
signals
to
categorize
1729
sites
across
continental
United
States
as
having
major
dam
influence,
shallow
or
deep
signatures,
lack
pronounced
(atmospheric)
signatures.
Approximately
40%
non-dam
have
substantial
contributions
indicated
by
characteristic
paired
signal
metrics.
Streams
with
signatures
account
for
half
all
signature
show
reduced
baseflow
a
higher
proportion
warming
trends
compared
These
findings
align
theory
that
is
more
vulnerable
increase
depletion.
atmospheric
tend
drain
watersheds
low
slope
greater
human
disturbance,
indicating
stream-groundwater
connectivity
in
populated
valley
settings.
Abstract
Headwater
catchments
are
the
fundamental
units
that
connect
land
to
ocean.
Hydrological
flow
and
biogeochemical
processes
intricately
coupled,
yet
their
respective
sciences
have
progressed
without
much
integration.
Reaction
kinetic
theories
prescribe
rate
dependence
on
environmental
variables
(e.g.,
temperature
water
content)
advanced
substantially,
mostly
in
well‐mixed
reactors,
columns,
warming
experiments
considering
characteristics
of
hydrological
at
catchment
scale.
These
shown
significant
divergence
from
observations
natural
systems.
On
other
hand,
theories,
including
transit
time
theory,
substantially
not
been
incorporated
into
understanding
reactions
Here
we
advocate
for
development
integrated
hydro‐biogeochemical
across
gradients
climate,
vegetation,
geology
conditions.
The
lack
such
presents
barriers
mechanisms
forecasting
future
Critical
Zone
under
human‐
climate‐induced
perturbations.
Although
integration
has
started
co‐located
measurements
well
way,
tremendous
challenges
remain.
In
particular,
even
this
era
“big
data,”
still
limited
by
data
will
need
(1)
intensify
beyond
river
channels
characterize
vertical
connectivity
broadly
shallow
deep
subsurface;
(2)
expand
older
dating
scales
reflected
stable
isotopes;
(3)
combine
use
reactive
solutes,
nonreactive
tracers,
(4)
augment
environments
undergoing
rapid
changes.
To
develop
it
is
essential
engage
models
all
stages
model‐informed
collection
strategies
maximize
usage;
adopt
a
“simple
but
simplistic,”
or
fit‐for‐purpose
approach
include
process‐based
models;
blend
data‐driven
framework
“theory‐guided
science.”
Within
hypothesis
testing,
model‐data
fusion
can
advance
mechanistically
link
catchments'
internal
structures
external
drivers
functioning.
It
only
field
hydro‐biogeochemistry,
also
enable
hind‐
fore‐casting
serve
society
large.
Broadly,
education
cultivate
thinkers
intersections
traditional
disciplines
with
hollistic
approaches
interacting
complex
earth
This
article
categorized
under:
Engineering
Water
>
Methods
Water Resources Research,
Journal Year:
2021,
Volume and Issue:
58(1)
Published: Oct. 22, 2021
Abstract
The
shallow
and
deep
hypothesis
suggests
that
stream
concentration‐discharge
(CQ)
relationships
are
shaped
by
distinct
source
waters
from
different
depths.
Under
this
hypothesis,
baseflows
typically
dominated
groundwater
mostly
reflect
chemistry,
whereas
high
flows
soil
water
chemistry.
Aspects
of
draw
on
applications
like
end
member
mixing
analyses
hydrograph
separation,
yet
direct
data
support
for
the
remains
scarce.
This
work
tests
using
co‐located
measurements
water,
groundwater,
streamwater
chemistry
at
two
intensively
monitored
sites,
W‐9
catchment
Sleepers
River
(Vermont,
United
States)
Hafren
Plynlimon
(Wales).
At
both
depth
profiles
subsurface
CQ
10
solutes
analyzed
broadly
consistent
with
hypothesis.
Solutes
more
abundant
(e.g.,
calcium)
exhibit
dilution
patterns
(concentration
decreases
increasing
discharge).
Conversely,
enriched
in
soils
nitrate)
generally
flushing
increases
may
hold
true
catchments
share
such
biogeochemical
stratifications
subsurface.
Soil
chemistries
were
estimated
high‐
low‐flow
average
relative
errors
ranging
24%
to
82%.
indicates
streams
mirror
waters:
can
be
used
infer
scarcely
measured
especially
where
there
members.
