Biology Reference
In-Depth Information
Chapter 3
Seaweed Responses to Temperature
Anja Eggert
3.1
Introduction
“Why don't seaweeds spread beyond their present boundaries along an uninterrupted
rocky coastline?”, asked Breeman in 1988. Two principal aspects play a central role
in shaping biogeographical distribution patterns: temperature-dependent effects on
performance (e.g., growth, photosynthesis) and temperature tolerance (i.e., survival).
The temperature responses of species are often correlated with the local thermal
environments, i.e., species are locally adapted, but may vary seasonally or among
populations or life stages due to phenotypic plasticity. Accordingly, it is necessary to
differentiate three types of temperature responses: (1) genetic adaptation to local
conditions, (2) phenotypic acclimation in response to variation of environmental
conditions, and (3) short-term physiological regulation. The responses take place
over different timescales: seconds to minutes (regulation), hours to days (acclima-
tion), and up to thousands of millions of years (adaptation). This chapter reviews the
temperature responses of seaweeds and their biogeographical implications.
3.2 Local Temperature Adaptation of Growth
and Photosynthesis
The effect of temperature on performance traits, such as growth and photosynthesis,
is typically visualized using temperature-response curves. Both growth and photo-
synthetic rates of seaweeds increase with temperature, plateau at a maximal level,
A. Eggert (
*
)
Leibniz Institute for Baltic Sea Research Warnem
unde, Section Physical Oceanography
and Instrumentation, Theoretical Oceanography and Numerical Modelling, Seestrasse 15,
18119 Rostock, Germany
e-mail:
anja.eggert@io-warnemuende.de
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