Warming exacerbates the impacts of ultraviolet radiation in temperate diatoms but alleviates the effect on polar species

Under global change scenarios, increasing sea surface temperatures and other factors have led to changes in oceanic environments. Phytoplankton, including marine diatoms, are exposed to multiple interacting drivers. The responses of polar and temperate diatoms to UV radiation differ. We exposedEntomoneis sp.,Thalassiosira weissflogii, andSkeletonema costatum to warming for 10  days and performed incubations under different radiation treatments. UV-induced inhibition was observed, with highest inhibition in polar diatom. However, warming alleviated UV-induced inhibition in polar diatom, while increasing the UV inhibition in two temperate diatoms. AbstractUnder global change scenarios, the sea surface temperature is increasing steadily along with other changes to oceanic environments. Consequently, marine diatoms are influenced by multiple ocean global change drivers. We hypothesized that temperature rise mediates the responses of polar and temperate diatoms to UV radiation (UVR) to different extents, and exposed the temperate centric diatoms,Thalassiosira weissflogii andSkeletonema costatum, and a polar pennate diatomEntomoneis sp., to warming (+5 °C) for 10 days, then performed short-term incubations under different radiation treatments with or without UVR. The effective quantum yields of the three diatoms were stable during exposure to PAR, but decreased when exposed to PAR + UVR, leading to significant UV-induced inhibition, which w as 3% and 9%, respectively, forT...

Source: Photochemistry and Photobiology - August 2, 2023 Category: Science Authors: Lixin Cao, Dongquan Bi, Wei Fan, Juntian Xu, John Beardall, Kunshan Gao, Yaping Wu Tags: RESEARCH NOTE Source Type: research