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EL
PAPEL
DEL
FITOPLACTON…..

ABSTRACT

The
role
of
phytoplankton
in
climate
change:
depends
our
future
of
some
small

microalgae?

Nowadays,
we
are
living
in
a
rapid
global
change
period
in
which
around
30,000

species
go
extinct
annually
due
to
those
human
activities
that
are
altering

biosphere-­-level
biogeochemistry
processes.
Biosphere
level
cycles
may
become
less

predictable
as
essential
microbes
succumb
to
climatic
change
and
anthropogenic

activities.
In
particular,
since
microalgae
and
cyanobacteria
play
an
important
role
in

control
of
global
change
because
they
are
the
principal
primary
producers
of
aquatic

ecosystems
producing
around
50%
total
photosynthesis.
Balance
between

respiration
-­-oxidation
(C6H12O6
+
6
O2
?
6
CO2
+
6
H2O)
and
photosynthesis
(6
CO2
+

6
H2O
?
C6H12O6
+
6
O2)
is
the
pacemaker
of
CO2
and
consequently
of
climatic

change.
Investigating
the
differential
capacity
of
the
response
of
phytoplankton
to

human-­-induced
environmental
forcing
has
become
a
key
issue
to
understanding

further
the
future
repercussions
on
the
functioning
of
ecosystems
at
planetary
level.

Our
studies
show
that
different
functional
phytoplanktonic
groups
(ie.
oceanic,

coastal,
coral-­-simbionts,
continental
phytoplankton…)
have
very
different
capability

for
adaptation
to
global
change.
The
capacity
of
different
microalgal
species
to

adapt
to
global
change
can
be
explained
in
relation
to
population
genetics
structure,

growth
rate,
mutation
rate,
ploidy,
habitat
preference
and
taxonomic
group.

Populations
of
oceanic
microalgae
showed
the
minimal
capacity
to
adapt
to
change.

Since
open
ocean
is
the
biggest
ecosystem
on
the
Earth,
future
perspectives
are
not

good.

Key
words:
Climatic
change;
CO2;
phytoplankton;
photosynthesis.

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