Biological weighting function for the mortality of Boeckella gracilipes (Copepoda, Crustacea) derived from experiments with natural solar radiation

BARBARA TARTAROTTI,; WALTER CRAVERO,; HORACIO ZAGARESE

PHOTOCHEMISTRY AND PHOTOBIOLOGY

Año: 2000 vol. 72 p. 314 - 319

0031-8655

We performed in situ experiments during the austral summer of 1998 to quantify the mortality of the freshwater copepod Boeckella gracilipes as a function of the UV dose. The copepods were exposed to solar radiation at the water-surface for ~24-34 h. Long-pass cut-off filters (Schott) were used in the exposure experiments. UV radiation and PAR were measured with an IL-1700 (International Light Inc.) and a PUV-500 radiometer (Biospherical Instruments Inc.). A biological weighting function for UV-induced mortality was calculated by fitting a model based on a logistic curve. Our results show that UV damage in this species is strongly wavelength- and dose-dependent. B. gracilipes was highly vulnerable to both UV-B (290-320 nm) and UV-A radiation (< 360 nm). The shape of the BWF obtained for B. gracilipes resembles more closely the action spectra for UV-induced erythema, than the action spectra for naked DNA.