ABSTRACT
This chapter focuses on the chemical composition of ice algae is reviewed and discussed in relation to the physiological ecology and adaptive strategies of the organisms. Annual sea ice in the Arctic and Antarctic contains favorable microhabitats within the ice or on the bottom surface of the ice which are colonized by microalgae. Information on the chemical composition and biochemistry of ice algae is useful for field ecology investigations and for providing an insight into the adaptive strategies of species living in the habitat. Estimation of the physiological state of microalgae by measurement of the cellular ratios of several defined chemical components may provide an indirect measure of growth rate. Certain chemical markers in microalgae may also be useful for demonstrating the relationship between different trophic levels. The most commonly used chemical markers in microalgae are fatty acids which are highly conserved in the predator.
