Biology Reference
In-Depth Information
other seaweed groups in order to gain insights into possible evolutionary issues
(Schmid et al.
1996
). Probably, one of the most important issues in seaweed
physiology will be the understanding of the complex interaction between the
expression and modulation of carbon metabolism, and processes underlying large
biogeographical patterns of seaweeds. For many aspects related to regulation of
carbon metabolism in seaweeds, proteomic and genomic studies are urgently
needed and fundamental in order to understand the role of seaweeds in present
and future scenarios of global change.
The consequences of increasing CO
2
levels and related phenomena such as the
ocean warming and ozone depletion on seaweed ecophysiology have begun to be
explored and different surveys describe various biological and geochemical
scenarios modified by anthropogenic activities (Israel and Einav
2010
). Due to
the dependence of RUBISCO on CO
2
, it has been postulated that photosynthetic
organisms will respond positively to present and future increases in atmospheric
CO
2
(Amthor
1995
). However, some experimental evidence suggests that large
increases in photosynthetic carbon fixation are not expected mainly because most of
the studied seaweeds exhibit CCMs (Gao et al.
1993
; Beer and Koch
1996
; Israel
and Hophy
2002
). Apparently, the focus could be on the increased competiveness
of algae without or with poorly developed CCM, which will depend on a series of
other environmental and geographic factors (Raven et al.
2002
). Overall, although
the studies compiled here give important insights into the potential responses of
organisms, the central question whether the mechanisms exploited by seaweeds
today allow them to adapt to future scenarios remains open.
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