Journal of Water and Health,
Journal Year:
2017,
Volume and Issue:
15(4), P. 509 - 518
Published: March 25, 2017
Saxitoxins
are
a
class
of
toxins
produced
by
at
least
two
groups
evolutionarily
distant
organisms
(cyanobacteria
and
dinoflagellates).
While
the
toxicity
these
is
relatively
well
characterized,
to
date
little
known
about
their
drivers
ecological
functions,
especially
in
lower
latitude
tropical
subtropical
freshwater
ecosystems.
In
present
study,
we
aimed
obtain
better
understanding
main
saxitoxin
concentrations
aquatic
environments.
We
investigated
relationships
among
mesotrophic
reservoir
dominated
cyanobacteria
Cylindrospermopsis
raciborskii
with
physical,
chemical
biological
water
variables.
The
highest
were
0.20
μg·L-1,
which
occurred
samples
densities
C.
(maximum
4.3
×
104
org·mL-1)
concentration
dissolved
nutrients
(nitrate
from
0.2
0.8
ortophosphate
0.3
8.5
μg·L-1).
These
correlations
confirmed
statistical
analyses.
However,
relative
(per
trichome)
associated
densities,
suggesting
that
production
or
selection
saxitoxin-producing
strains
was
adaptation
this
species
conditions
stress.
Our
results
indicate
toxin
yields
vary
depending
on
enrichment
having
potential
implications
for
management.
International Journal of Environmental Research and Public Health,
Journal Year:
2023,
Volume and Issue:
20(3), P. 1984 - 1984
Published: Jan. 21, 2023
Water
blooms
caused
by
the
invasive
cyanobacterium
Raphidiopsis
raciborskii
occur
in
many
reservoirs
tropical
and
subtropical
regions
of
China.
In
recent
decades,
this
species
has
spread
rapidly
to
temperate
regions.
Phenotypic
plasticity
climate
warming
are
thought
promote
worldwide
dispersion
R.
raciborskii.
However,
investigations
into
genetic
phenotypic
diversities
have
revealed
significant
intraspecific
heterogeneity.
particular,
competition
between
Microcystis
aeruginosa
was
highly
strain
dependent.
Although
concept
an
ecotype
proposed
explain
heterogeneity
strains
with
different
geographic
origins,
microevolution
is
more
reasonable
for
understanding
coexistence
phenotypes
genotypes
same
environment.
It
been
suggested
that
derived
from
a
strong
driving
force
expansion
Additionally,
temperature,
nutrient
fluctuations,
grazer
disturbance
critical
environmental
factors
affect
population
establishment
new
environments.
The
present
review
provides
insights
ecological
mechanisms
underlying
invasion
Chinese
freshwater
ecosystems.
FEMS Microbiology Ecology,
Journal Year:
2017,
Volume and Issue:
93(4)
Published: March 8, 2017
Mechanisms
behind
expansion
of
an
invasive
cyanobacterium
Cylindrospermopsis
raciborskii
have
not
been
fully
resolved,
and
different
hypotheses,
such
as
global
warming,
are
suggested.
In
the
East-Central
Europe,
it
is
widely
occurring
in
western
part
Poland
but
only
single
locations
East
due
to
some
limiting
factors.
Therefore,
broad-scale
phytoplankton
survey
including
117
randomly
selected
lakes
Lithuania
was
conducted.
The
results
showed
that
C.
occurred
absent
from
other
regions
except
one
lake.
which
present
had
higher
annual
mean
air
temperature,
maximum
temperature
warmest
month
minimum
coldest
month,
demonstrating
average
indirectly,
duration
growing
season
might
be
more
important
factor
driving
distribution
than
measured
situ
water
temperature.
turn,
presence
localities
may
related
physiological
adaptations
separated
ecotype.
Collectively,
these
provide
novel
evidence
on
influence
East-European
also
indicate
high
ecological
plasticity
this
species.
