UV-B辐射增强对褶皱臂尾轮虫实验种群动态的影响

Effects of UV-B Radiation on the Experimental Population Dynamics of the Rotifer Brachionus plicatilis

采用单个体培养和生命表技术,研究了不同UV-B辐射剂量对褶皱臂尾轮虫(Brachionus plicatilis)实验种群的存活时间、产卵量、生殖率和内禀增长率等关键种群参数的影响.结果表明,UV-B辐射可使轮虫的存活时间显著缩短(p<0.05),对照组轮虫存活时间最长,在本实验条件下达390 h;最大剂量1.20 kJ/m2处理组最短,为300 h.低剂量的0.24、0.48和0.72 kJ/m2UV-B辐射促进了褶皱臂尾轮虫的繁殖,而高剂量的0.96和1.20 kJ/m2UV-B辐射抑制了褶皱臂尾轮虫的繁殖.褶皱臂尾轮虫的生命期望随UV-B辐射剂量的增大呈一致性缩短,可以作为大气UV-B辐射强弱的生物指标.

Using clonal culture and life table techniques, we studied the effect of UV-B radiation whose experimental dose were 0.00, 0.24, 0.48, 0.72, 0.96 and 1.20 kJ /m^2 on experimental population dynamics of the rotifer Brachionus plicatilis feeding on algae Chlorella sp. with a density of 1.0× 10^6 cells/ ml at （23±1）℃. The main results were as follows. （1） The survival time of the rotifer Brachionus plicatilis was significantly shortened by UV-B radiation treatment （p〈0.05） and the longest survival time with 390 h occurred in the control, while the shortest with 300 h appeared in the highest UV-B radiation treatment （1.20 kJ/m^2） ; （2） The fecundity of the rotifer was notably affected by UV B radiation （p〈0.05） and was promoted by the lower UV-B radiation treatment （0.24, 0.48 and 0.72 kJ/m^2） but inhibited by the higher UV-B radiation treatment （0.96 and 1.20 kJ/m^2 ） ; （3） The life expectancy was also obviously affected by UV-B radiation （p〈0.05） . The highest Life expectancy was recorded in the control and became shorter with the dose increas of the UV B radiation, indicating that the life expectancy of the rotifer Brachionus plieatilis can be used as an ideal index for the enhancement of UV- B radiation.