Influence of UV Radiation on Four Freshwater Invertebrates¶

Abstract

Laboratory tests confirmed a negative and variable response of the following four species to artificial UV radiation: Cypridopsis vidua, an ostracode; Chironomus riparius, a midge larvae; Hyalella azteca, an amphipod; and Daphnia magna, a daphnid. Severe damage occurred at UV-B irradiance ranging from 50 to 80% of incident summer values. Under constant exposure to UV and photosynthetically active radiation (PAR) the acute lethal response was recorded at 0.3, 0.8, 0.8 and 4.9 W m-2 UV-B for D. magna, H. azteca, C. riparius and C. vidua, respectively. Sublethal UV-B damage to invertebrates included impaired movement, partial paralysis, changes in pigmentation and altered water balance (bloating). A series of UV-B, UV-A and PAR treatments, applied separately and in combination, revealed a positive role for both UV-A and PAR in slowing down UV-B damage. Mean lethal concentration values of the species typically more tolerant to UV and PAR (Cypridopsis, Chironomus) decreased conspicuously when both UV-A and PAR were eliminated. For UV-B-sensitive species (Hyalella, Daphnia) these differences were notably smaller. We suggest that this gradation of sensitivity among the tested species demonstrates potential differences in repairing mechanisms which seem to work more efficiently for ostracodes and chironomids than for amphipods and daphnids. Manipulations with a cellulose acetate filter showed that lower range UV-B (280-290 nm), produced by FS-40 lamps, may cause excessive UV damage to invertebrates.

The Bunsen–Roscoe reciprocity law in ultraviolet-B-induced mortality of the two-spotted spider mite Tetranychus urticae

“…Divergence from the reciprocity law was observed in aquatic animals under UVB radiation at low intensity such as 0.2-0.4 W m −2 (Cywinska et al, 2000;Wübben, 2000), suggesting a presence of damage threshold by UVB intensity. In contrast, reciprocity was applicable to mortality of T. urticae eggs even if those were exposed to very low-intensity UVB radiation (0.014-0.023 W m −2 ).…”

“…However, mortality of shrimp zoea after UVB irradiation at low intensity (0.2 W m −2 ) diverged from the reciprocity law, which had been upheld under radiation at higher irradiances (Wübben, 2000). Similar divergence from reciprocity in UVB damage was also found for several cases of aquatic animals (Cywinska et al, 2000). Therefore, applicability of the reciprocity law to UV damage in organisms is still disputable.…”

Photocatalytic properties of titanium dioxide nanoparticles affect habitat selection of and food quality for a key species in the leaf litter decomposition process

“…1a). This active habitat selection of gammarids is most likely explained by the potential of UV-B irradiation to induce acute toxicity towards macroinvertebrates (in terms of damaged cells and tissues; Obermüller et al, 2007), observed even at intensities as low as 0.8 W/m 2 (Cywinska et al, 2000). As the present study used a comparable UV-B-intensity (i.e.…”

Extreme tolerance to environmental stress of sexual and parthenogenetic resting eggs of Eucypris virens (Crustacea, Ostracoda)

“…A depletion of the stratospheric ozone layer, as expected under many climate change scenarios, will increase the exposure to damaging radiation. The freshwater ostracods Heterocypris incongruens and Cypridopsis vidua (Mü ller) are highly tolerant to UV-B radiation (Hurtubise, Havel &Little, 1998 andCywinska, Crump &Lean, 2000;respectively), and preliminary experiments with E. virens indicated that its greenly pigmented valves provide protection against UV (Van den Broecke, Schö n & Martens, 2007).…”