Influence of Ozone-Related Increases in Ultraviolet Radiation on Antarctic Marine Organisms

Abstract

SYNOPSIS. Every spring for the past two decades, depletion of stratospheric ozone has caused increases in ultraviolet B radiation (UVB, 280-320 nm) reaching Antarctic terrestrial and aquatic habitats. Research efforts to evaluate the impact of this phenomenon have focused on phytoplankton under the assumption that ecosystem effects will most likely originate through reductions in primary productivity; however, phytoplankton do not represent the only significant component in ecosystem response to elevated UVB. Antarctic bacterioplankton are adversely affected by UVB exposure; and invertebrates and fish, particularly early developmental stages that reside in the plankton, are sensitive to UVB. There is little information available on UV responses of larger Antarctic marine animals (e.g., birds, seals and whales). Understanding the balance between direct biological damage and species-specific potentials for UV tolerance (protection and recovery) relative to trophic dynamics and biogeochemical cycling is a crucial factor in evaluating the overall impact of ozone depletion. After more than a decade of research, much information has been gathered about UV-photobiology in Antarctica; however, a definitive quantitative assessment of the effect of ozone depletion on the Antarctic ecosystem still eludes us. It is only obvious that ozone depletion has not had a catastrophic effect in the Antarctic region. The long-term consequences of possible subtle shifts in species composition and trophic interactions are still uncertain.

Radiation effects along a UV-B gradient on species composition and diversity of a shallow-water macrobenthic community in the western Baltic

“…More recently, an (albeit limited) number of studies were also unable to confirm inhibitory UVR effects on benthic community diversity (DeNicola & Hoagland 1996, Keller et al 1997, Kiffney et al 1997, Santas et al 1998. This startling lack of UVR effects on the diversity of macrobenthic communities contradicts the large number of detrimental UVR effects reported at the organismal and species level, with some of the latter effects also apparent at our study site (Wängberg et al 1996, Franklin & Forster 1997, Häder et al 1998, Aguilera et al 1999, Karentz & Bosch 2001, Montero et al 2002.…”

Impact of climate change on Antarctic krill

“…Elevated UV radiation is known to impact marine organisms (Karentz 1991, Naganobu et al 1999, Karentz & Bosch 2001. The direct impact of UV-B on the krill population can occur through genetic damage (Jarman et al 1999, Dahms et al 2011), physiological effects (Newman et al , 2000 or through behavioural reactions (Newman et al 2003).…”

Comprehensive evaluation of the palatability and chemical defenses of subtidal macroalgae from the Antarctic Peninsula

“…Other than mycosporine-like amino acids (MAAs), which defend against UV radiation damage and are common in marine macroalgae throughout the world (McClintock & Karentz 1997, Hoyer et al 2001, Karentz 2001, Karentz & Bosch 2001, we are not aware of reports of nitrogen-containing secondary metabolites in Antarctic macroalgae. To date, 50 non-MAA secondary metabolites have been reported from Antarctic macroalgae (Amsler et al 2001b, Ankisetty et al 2004, Blunt & Munro 2004, none of which contain nitrogen.…”