Eutrophication‐induced dinoflagellate succession contributes to marine carbon sequestration through refractory dissolved organic matter accumulation
Limnology and Oceanography,
Год журнала:
2025,
Номер
unknown
Опубликована: Май 27, 2025
Abstract
The
increasing
eutrophication
of
coastal
seas
is
causing
a
shift
in
the
most
important
phytoplankton
groups
from
diatoms
to
dinoflagellates,
but
its
feedback
marine
carbon
cycling
remains
unclear.
Here,
we
investigated
potential
key
phytoplankton,
diatom
Skeletonema
costatum
,
and
dinoflagellate
Prorocentrum
donghaiense
for
refractory
dissolved
organic
(DOC)
accumulation
over
dark
degradation
incubations
70
d.
Our
multi‐method
approach
showed
that
detritus,
rather
than
significantly
contributes
DOC.
This
evidenced
by
fact
detritus
dinoflagellates
compared
(1)
has
weaker
transmittance
infrared
spectrometry,
indicating
lower
content
labile
substances
(alcohol
amide
groups);
(2)
higher
release
and/or
transformation
efficiency
particulate
DOC
(81%
vs.
50%);
(3)
fraction,
amino
acid
(8%
17%
carbon)
exhibits
degradability
formed
(23%
30%);
(4)
compounds
determined
Fourier
transform
ion
cyclotron
resonance
mass
spectrometry
(maximum
molecular
lability
boundary:
21%
31%);
(5)
proportion
carboxylic‐rich
alicyclic
molecules
(57%
±
0.5%
51%
0.7%)
incubations.
results
emphasize
eutrophication‐triggered
succession
significant
positive
sequestration
through
formation
Язык: Английский
Prorocentrum insidiosum sp. nov. (Prorocentrales, Dinophyceae): Morphological and Phylogenetic Characterization of a Mucosphere Producing Dinoflagellate From the “cordatum Group”
Journal of Eukaryotic Microbiology,
Год журнала:
2025,
Номер
72(4)
Опубликована: Май 30, 2025
ABSTRACT
Prorocentrum
cf.
balticum
was
the
provisional
designation
assigned
to
strains
of
a
small,
pelagic,
mixoplanktonic
dinoflagellate
found
produce
carbon‐rich
mucilage‐based
prey
capture
devices,
termed
“mucospheres.”
Here
we
characterize
morphology
and
phylogeny
strains,
describe
them
as
insidiosum
sp.
nov.,
discuss
common
morphological
features
among
six
species
phylogenetically
defined
P.
cordatum
group.
Cells
nov.
were
round
slightly
ovate
in
lateral
view,
12–16
μm
long
8–15
deep,
laterally
compressed.
Scanning
electron
microscopy
revealed
thecal
plates
densely
ornamented
with
short
spines
there
two
size
classes
pores
irregularly
distributed
across
both
plates,
row
four
large
apical‐ventral
position
on
right
plate.
The
periflagellar
area
consisted
eight
platelets,
prominent
wing‐like
apical
projections
form
double
layered
curved
structure
platelet
1
additional
most
other
platelets
except
4.
is
distinct
from
all
genetically
represented
within
genus
possesses
unique
combination
differentiating
it
protologues
small
species.
Язык: Английский