Water Research,
Journal Year:
2019,
Volume and Issue:
169, P. 115201 - 115201
Published: Oct. 18, 2019
Dissolved
organic
matter
(DOM)
in
groundwater
is
fundamentally
important
with
respect
to
biogeochemical
reactions,
global
carbon
cycling,
heavy
metal
transport,
water
treatability
and
potability.
One
source
of
DOM
from
the
transport
vadose
zone
by
rainfall
recharge.
Changes
precipitation
patterns
associated
natural
climate
variability
change
are
expected
alter
load
character
released
these
areas,
which
ultimately
impacts
on
quality
treatability.
In
order
investigate
potential
changes
after
recharge,
we
sampled
shallow
a
coastal
peat-rich
sand
aquifer
New
South
Wales,
Australia,
during
an
extended
period
low
(average
daily
rate
<
1.6
mm
day−1
over
8
months
prior
sampling),
two
events
(84
98
respectively).
We
assess
composition
correcting
for
dilution
novel
combination
advanced
analytical
techniques:
liquid
chromatography
detection
(LC-OCD)
negative-ion
electrospray
ionization
Fourier
transform
ion
cyclotron
resonance
mass
spectrometry
(FT-ICR
MS).
also
chemistry
pre-
post-rainfall.
Post-rainfall,
show
that
dilution-corrected
amount
highly
aromatic
molecular
formulae
(i.e.
those
categorised
into
groups
polyphenolics
condensed
aromatics)
were
1.7
2.0
times
higher
respectively
than
pre-rainfall
samples.
attribute
this
flushing
peat-derived
buried
material
groundwater.
identify
periods
can
lead
hydrophilic/HOC
ratios
(median
=
4.9,
n
14).
Redundancy
analysis
(RDA)
was
used
compare
HOC
fraction
FT-ICR
MS
compound
groups.
has
more
samples,
less
similar
post-rainfall
This
suggests
decline
water-borne
hydrophobics
observed
could
be
preferential
adsorption
hydrophobic
DOM,
making
samples
treatable
potable
supply.
Post-rainfall
observe
significant
increases
arsenic
(leading
concentrations
greater
3
World
Health
Organisation
drinking
limit
10
μg
/
L).
Increases
due
may
therefore
peatland
areas
ways
impact
bioavailability,
increase
concentrations,
reducing
ease
treatment
human
consumption.
To
best
our
knowledge,
first
study
chemical
sedimentary
rich
environment
through
multiple
techniques.
Environmental Science & Technology,
Journal Year:
2021,
Volume and Issue:
55(22), P. 15090 - 15099
Published: Sept. 15, 2021
Microbially
derived
extracellular
polymeric
substances
(EPSs)
occupy
a
large
portion
of
dissolved
organic
matter
(DOM)
in
surface
waters,
but
the
understanding
photochemical
behaviors
EPS
is
still
very
limited.
In
this
study,
characteristics
from
different
microbial
sources
(Shewanella
oneidensis,
Escherichia
coli,
and
sewage
sludge
flocs)
were
investigated
terms
production
reactive
species
(RS),
such
as
triplet
intermediates
(3EPS*),
hydroxyl
radicals
(•OH),
singlet
oxygen
(1O2).
The
steady-state
concentrations
•OH,
3EPS*,
1O2
varied
ranges
2.55–8.73
×
10–17,
3.01–4.56
10–15,
2.08–2.66
10–13
M,
respectively,
which
within
range
reported
for
DOM
other
sources.
RS
among
isolates
due
to
diversity
their
composition.
A
strong
degradation
protein-like
components
was
identified
by
excitation
emission
matrix
fluorescence
with
parallel
factor
analysis,
relatively,
humic-like
remained
stable.
Fourier-transform
ion
cyclotron
resonance
mass
spectrometry
further
revealed
that
aliphatic
resistant
irradiation,
while
portions
lower
H/C
ratios
higher
O/C
more
susceptible
photolysis,
leading
phototransformation
saturation
aromaticity.
With
EPS,
could
effectively
promote
antibiotic
tetracycline.
findings
study
provide
new
insights
into
photoinduced
self-evolution
interrelated
fate
contaminants
aquatic
environment.
npj Biodiversity,
Journal Year:
2024,
Volume and Issue:
3(1)
Published: Feb. 7, 2024
Rivers
are
an
important
component
of
the
global
carbon
cycle
and
contribute
to
atmospheric
exchange
disproportionately
their
total
surface
area.
Largely,
this
is
because
rivers
efficiently
mobilize,
transport
metabolize
terrigenous
organic
matter
(OM).
Notably,
our
knowledge
about
magnitude
globally
relevant
fluxes
strongly
contrasts
with
lack
understanding
underlying
processes
that
transform
OM.
Ultimately,
OM
processing
en
route
oceans
results
from
a
diverse
assemblage
consumers
interacting
equally
pool
resources
in
spatially
complex
network
heterogeneous
riverine
habitats.
To
understand
interaction
between
OM,
we
must
therefore
account
for
spatial
configuration,
connectivity,
landscape
context
at
scales
ranging
local
ecosystems
entire
networks.
Building
such
explicit
framework
fluvial
across
may
also
help
us
better
predict
poorly
understood
anthropogenic
impacts
on
cycling,
instance
human-induced
fragmentation
changes
flow
regimes,
including
intermittence.
Moreover,
current
unprecedented
human-driven
loss
biodiversity.
This
least
partly
due
mechanisms
operating
scales,
as
interference
migration
habitat
homogenization,
comes
largely
unknown
functional
consequences.
We
advocate
here
comprehensive
networks
connecting
two
aware
but
disparate
lines
research
(i)
metacommunities
biodiversity,
(ii)
biogeochemistry
contribution
cycle.
argue
agenda
focusing
regional
scale-that
is,
river
network-to
enable
deeper
mechanistic
naturally
arising
biodiversity-ecosystem
functioning
coupling
major
driver
biogeochemically
fluxes.
