First
posted
April
16,
2018
For
additional
information,
contact:
National
Water-Quality
Assessment
(NAWQA)
ProjectU.S.
Geological
Survey413
Center12201
Sunrise
Valley
DriveReston,
Virginia
20192
Healthy
streams
and
the
fish
other
organisms
that
live
in
them
contribute
to
our
quality
of
life.
Extensive
modification
landscape
Midwestern
United
States,
however,
has
profoundly
affected
condition
streams.
Row
crops
pavement
have
replaced
grasslands
woodlands,
been
straightened,
wetlands
fields
drained.
Runoff
from
agricultural
urban
land
brings
sediment
chemicals
What
is
chemical,
physical,
biological
streams?
Which
physical
chemical
stressors
are
adversely
affecting
communities,
what
their
origins,
how
might
we
lessen
or
avoid
adverse
effects?In
2013,
U.S.
Survey
(USGS)
conducted
Midwest
Stream
Quality
evaluate
human
activities
affect
In
collaboration
with
Environmental
Protection
Agency
Rivers
Streams
Assessment,
USGS
sampled
100
streams,
chosen
be
representative
different
types
watersheds
region.
Biological
was
evaluated
based
on
number
diversity
fish,
algae,
invertebrates
Changes
habitat
characteristics
streams—"stressors"—were
assessed,
relation
factors
explored
by
using
mathematical
models.
The
data
models
help
us
better
understand
Environmental Science & Technology,
Год журнала:
2018,
Номер
53(1), С. 452 - 462
Опубликована: Дек. 11, 2018
Multiple
physical
and
chemical
stressors
can
simultaneously
affect
the
biological
condition
of
streams.
To
better
understand
complex
interactions
land-use
practices,
water
quality,
ecological
integrity
streams,
U.S.
Geological
Survey
National
Water
Quality
Assessment
Project
is
conducting
regional-scale
assessments
stream
across
United
States.
In
summer
2013,
weekly
samples
were
collected
from
100
streams
in
Midwestern
Employing
watershed
theory,
we
used
structural
equation
modeling
(SEM)
to
represent
a
general
hypothesis
for
how
16
variables
(previously
identified
be
important
condition)
might
inter-related.
Again,
using
SEM,
evaluated
ability
this
"stressor
network"
explain
variations
multimetrics
algal,
invertebrate,
fish
community
health,
trimming
away
any
environmental
not
contributing
an
explanation
responses.
Seven
variables-agricultural
urban
land
use,
sand
content
soils,
basin
area,
percent
riparian
area
as
forest,
channel
erosion,
relative
bed
stability-were
found
all
three-community
metrics.
The
algal
invertebrate
models
included
water-chemistry
model.
Results
suggest
that
Midwest
are
affected
by
both
agricultural
uses
natural
geologic
setting,
indicated
soils.
Chemicals
related
crops
(pesticides
nutrients)
residential
(pyrethroids)
more
strongly
than
factors
(riparian
soil
character).
The Science of The Total Environment,
Год журнала:
2024,
Номер
915, С. 169634 - 169634
Опубликована: Янв. 24, 2024
Multistressor
studies
were
performed
in
five
regions
of
the
United
States
to
assess
role
pesticides
as
stressors
affecting
invertebrate
communities
wadable
streams.
Pesticides
and
other
chemical
physical
measured
75
99
streams
per
region
for
4
weeks,
after
which
surveyed
(435
total
sites).
sampled
weekly
filtered
water,
once
bed
sediment.
The
a
stressor
was
assessed
by
evaluating
multiple
lines
evidence:
toxicity
predictions
based
on
pesticide
concentrations,
multivariate
models
statistical
analyses,
previously
published
mesocosm
experiments.
Toxicity
using
benchmarks
species
sensitivity
distributions
correlations
suggested
that
present
at
high
enough
concentrations
adversely
affect
regional
scale.
Two
undirected
techniques—boosted
regression
tree
distance-based
linear
models—identified
predictors
(respectively)
metrics
community
composition.
To
put
insecticides
context
with
known,
influential
covariates
response,
generalized
additive
used
identify
individual
pesticide(s)
important
condition
each
region,
accounting
natural
covariates.
Four
identified
scale:
bifenthrin,
chlordane,
fipronil
its
degradates,
imidacloprid.
Fipronil
particularly
Southeast
imidacloprid,
chlordane
regions.
For
fipronil,
supported
experiments
demonstrated
adverse
effects
naïve
aquatic
when
dosed
under
controlled
conditions.
These
evidence
do
not
prove
causality—which
is
challenging
field
multistressor
conditions—but
they
make
strong
case
within
Environmental Science & Technology,
Год журнала:
2020,
Номер
55(2), С. 902 - 911
Опубликована: Дек. 24, 2020
Elevated
nitrogen
concentrations
in
streams
and
rivers
the
Chesapeake
Bay
watershed
have
adversely
affected
ecosystem
health
of
bay.
Much
this
is
derived
as
nitrate
from
groundwater
that
discharges
to
base
flow.
In
study,
boosted
regression
trees
(BRTs)
were
used
relate
flow
(n
=
156)
explanatory
variables
describing
sources,
geology,
soil
catchment
characteristics.
From
these
relations,
a
BRT
model
was
developed
predict
throughout
watershed.
The
highest
associated
with
intensive
agricultural
land
use,
carbonate
sparse
riparian
canopy,
which
suggested
reduced
inputs,
particularly
over
terrane,
are
critical
for
limiting
concentrations.
lowest
extensive
high
levels
organic
carbon
soils,
suboxic
conditions
at
shallow
depths,
denitrification
subsurface,
zone,
Nitrate
transport
aquifers
can
take
decades
occur,
resulting
decades-long
lag
times
between
time
when
land-use
activity
implemented
its
effects
fully
observed
streams.
Predictive
models
will
help
identify
portions
likely
large
fractions
total
stream
load
pathways
significant
times.
Diversity,
Год журнала:
2023,
Номер
15(5), С. 636 - 636
Опубликована: Май 8, 2023
The
types
and
intensification
of
land
use
in
the
watershed
affect
living
organisms
aquatic
ecosystems
differently;
this
impact
will
also
vary
according
to
temporal
spatial
scales.
Understanding
these
interactions
is
crucial
design
biomonitoring
programs
detect
effect
different
pollutants
freshwater
improve
management
conservation
strategies.
Therefore,
paper
qualitatively
reviews
studies
evaluate
on
multiple
scales
watersheds.
organized
into
four
sections.
first
section
presents
systems
(streams,
rivers,
lakes,
reservoirs).
In
second
section,
we
describe
characteristics
main
types.
third
explain
how
biomonitoring.
Finally,
fourth
focus
planning
future
prediction
discuss
models
eDNA
Our
review
assist
decision-making
regarding
watersheds
guide
bioindicators
for
various
diverse
worldwide.
