INVESTIGADORES
VILLAFAÑE virginia Estela
capítulos de libros
Título:
Ultraviolet radiation effects on macroalgae from Patagonia, Argentina
Autor/es:
HELBLING, E.W; V.E. VILLAFAÑE; D.-P. HÄDER
Libro:
Seaweeds and their role in globally changing environments
Editorial:
Springer
Referencias:
Año: 2010; p. 199 - 214
Resumen:
Aquatic ecosystems account for almost half of primary production on our planet, matching the combined productivity of all terrestrial ecosystems. While most of aquatic productivity is due to phytoplankton, macroalgae contribute for a significant share, especially in coastal areas. In their natural environment, macroalgae are generally exposed to excessive solar PAR (photosynthetic active radiation, 400 – 700 nm) as well as to ultraviolet radiation, (UV-B, 280 – 315 nm and UV-A, 315 – 400 nm) especially in the upper eulittoral and the supralittoral. The coincidence of low tides and high solar angles results in the highest radiation stress, generally reflected as photoinhibition i.e., the reduction in photosynthetic rates. Photoinhibition is determined not only in macroalgae from the tropics and temperate zones but also in Arctic and Antarctic environments. Most of the observed photoinhibition is due to PAR, as this waveband has a high proportion of solar radiation energy reaching the Earth’s surface. However, in the top meters of the water column a significant percentage of photoinhibition is caused by UV-B, and to less extent by UV-A. In this chapter we will review our knowledge on the effects of solar radiation on macroalgae from Patagonia, Argentina. This area is especially important from a photobiological point of view, as it presents high heliophany and episodic ozone depletion events. Although relatively few studies were conducted in this area, most of them were performed under in situ conditions and thus the information is highly valuable as it reflects the natural conditions of the area.