Life strategy, ecophysiology and ecology of seaweeds in polar waters

Abstract

Polar seaweeds are strongly adapted to the low temperatures of their environment, Antarctic species more strongly than Arctic species due to the longer cold water history of the Antarctic region. By reason of the strong isolation of the Southern Ocean the Antarctic marine flora is characterized by a high degree of endemism, whereas in the Arctic only few endemic species have been found so far. All polar species are strongly shade adapted and their phenology is finely tuned to the strong seasonal changes of the light conditions. The paper summarises the present knowledge of seaweeds from both polar regions with regard to the following topics: the history of seaweed research in polar regions; the environment of seaweeds in polar waters; biodiversity, biogeographical relationships and vertical distribution of Arctic and Antarctic seaweeds; life histories and physiological thallus anatomy; temperature demands and geographical distribution; light demands and depth zonation; the effect of salinity, temperature and desiccation on supraand eulittoral seaweeds; seasonality of reproduction and the physiological characteristics of C. Wiencke (&) AE U. H. Lü der

The influence of the geomorphological and sedimentological settings on the distribution of epibenthic assemblages on a flat topped hill on the over-deepened shelf of the western Weddell Sea (Southern Ocean)

“…In addition, the presence of macroalgae can be used to indicate the light level critical for photosynthesis (Gómez et al, 1997). In general, off the Antarctic Peninsula large macroalgae like Himantothallus grandifolius have been found at water depths up to 90 m, and smaller foliose and filamentous algae can occur at even greater depths (Wiencke et al, 2007). Due to the shallow water depth, and similar to most shallow areas on the Antarctic shelves, the impact of iceberg scouring (e.g.…”

Diurnal changes in photosynthetic activity of the biological soil crust and lichen: Effects of abiotic factors (Petuniabukta, Svalbard)

“…All polar species are strongly adapted to environmental stresses such as low temperature, different levels of irradiation or lack of water and their phenology is finely tuned to the strong seasonal changes of the environmental factors. Arctic species are less adapted to environmental stresses than Antarctic one due to shorter cold history (Wiencke et al 2006).…”

Oxidative balance in macroalgae from Antarctic waters. Possible role of Fe

“…According to Wiencke (1990), G. skottsbergii belongs to seasonal responders who start growing later coinciding with favorable light conditions in spring and summer. The seasonal responder algae react directly to the changing environmental conditions and show an opportunistic life strategy (Wiencke et al, 2007). Although they are adapted to skip rough abiotic conditions G. skottsbergii seemed to be more sensitive to the external stress.…”

“…Extreme seasonal variations in light regime, low temperatures, and extended periods of ice cover and snow characterize the Polar Regions (Wiencke et al, 2007). Particularly over the West Antarctic Peninsula, glacial retreat has increased over the last decades due to global warming (Rückamp et al, 2011) impacting on benthic ecosystems (Gutt et al, 2015).…”

“…The brown macroalga Himantothallus grandifolius (Gepp and Gepp) Zinova 1959, inhabiting Antarctic waters, is the largest Antarctic seaweed (up to 10 m thallus length). Whereas G. skottsbergii occurs predominantly in shallow waters, H. grandifolius mostly occurs in deeper waters on vertical rocks and boulders in conditions of moderate to low turbulence and on less stable substrata, such as pebbles and gravels (Wiencke et al, 2007). Both species have completely different life strategies.…”