Synergic effect between temperature and ultraviolet radiation on aquatic

P. E. GARCÍA, M. C DIEGUEZ & H. E. ZAGARESE

Lake Placid, Florida , USA

Conferencia; GLEON 6; 2008

GLEON

It is well known that the increase in solar irradiance is threatening both ecosystem and organism of mid inhabiting mid and high latitudes of the earth. At the organism level, different mechanisms and strategies provide protection to endure life at high irradiance and particularly, to cope with high ultraviolet radiation (RUV) levels. The accumulation of Photoprotective compounds (PPCs), such as carotenoids and mycosporine-like amino acids (MAAs) has been shown to improve the survivorship of aquatic organisms exposed to high levels of RUV. In this study we analyzed the variability of carotenoids and MAAs in a calanoid copepod in relation to temperature and RUV. The crustaceans were collected from the shallow pond “Los Juncos” (North Patagonia, Argentina). The results of laboratory incubation show up that PPCs (both MAAs and Carotenoids) were highest at 16ºC in the presence of visible light (PAR + UV-A). Remarkably the survivorship of the copepod decrease with increasing temperature and in the presence of visible light. This may be related to the fact that Boeckella species are cold-adapted and as reflected by they occurrence at mid and lower latitudes during cold months. Thus, as reflected by they occurrence at mid and lower latitudes during cold months. Thus, as reflected by they occurrence at mid and lower latitudes during cold months. Thus, as reflected by they occurrence at mid and lower latitudes during cold months. Thus, Boeckella species are cold-adapted and as reflected by they occurrence at mid and lower latitudes during cold months. Thus, Boeckella may be vulnerable to the increase in temperature which could condition their occurrence resulting in changes in geographical distribution as has been observed in several different animal and plant. occurrence resulting in changes in geographical distribution as has been observed in several different animal and plant. occurrence resulting in changes in geographical distribution as has been observed in several different animal and plant. occurrence resulting in changes in geographical distribution as has been observed in several different animal and plant. may be vulnerable to the increase in temperature which could condition their occurrence resulting in changes in geographical distribution as has been observed in several different animal and plant.