Differential Photosynthetic Response of a Green Tide Alga Ulva linza to Ultraviolet Radiation, Under Short ‐ and Long‐term Ocean Acidification Regimes

We investigate the response ofUlva linza to UV radiation in the form of photosynthetically active radiation or PAB radiation. Radiation exposures were assessed following long ‐term and short‐term OA treatments. Results showed that increased CO2 decreased the damage and repair rate of thalli grown under short ‐term OA conditions with PAB treatment. In thalli, k was increased following PAB treatment at long‐term OA conditions. These results show that blooming algae may be more sensitive to UV radiation in marine environments, but it can develop effective mechanisms to offset the negative effects, refl ecting acclimation to long‐term OA conditions. AbstractBoth ocean acidification (OA) and solar ultraviolet (UV) radiation can bring about changes in macroalgal physiological performance. However, macroalgal responses to UV radiation when acclimatized to OA under different time scales are rare. Here, we investigate the response ofUlva linza, a green tide alga, to UV radiation in the form of photosynthetically active radiation (PAR) or PAB (PAR+UVA+UVB) radiation. Radiation exposures were assessed following long ‐term (from spore to adult stage, 1 month) and short‐term (adult stage, 1 week) OA treatments. Results showed that increased CO2 decreased the damage rate (k) and repair rate (r) of thalli grown under short ‐term OA conditions with PAB treatment, the ratio ofr:k was not altered. Following long ‐term OA conditions, r was not affected, although k was increase...

Source: Photochemistry and Photobiology - July 18, 2019 Category: Science Authors: Jing Ma, Wen Wang, Liming Qu, Xiaoyan Liu, Zhiqin Wang, Sen Qiao, Hailong Wu, Guang Gao, Juntian Xu Tags: Research Article Source Type: research