Fig. 4
Effects of ultraviolet-B (UVB) and photosynthetically active radiation (PAR) on the relative electron transport rate (rETR) of rapid light response curves (RLCs) and the parameters of the RLCs in Ulva prolifera on the 1st day and the 4th day. A The relative electron transfer rate (rETR) of the RLCs on the 1st day in the SHAM-free group; B the rETR of the RLCs on the 1st day in the SHAM group; C the rETR of the RLCs on the 4th day in the SHAM-free group; D The rETR of the RLCs on the 4th day in the SHAM group; E maximum relative electron transfer rate (Pm); F photosynthetic rate in the light-limited region of the RLC (α); G minimum saturated irradiance (Ik). SHAM-1d and SHAM-4d show the changes of the SHAM group on the 1st day and the 4.th day, respectively. All data are the mean values (± SD) from three biological replicates. Groups with different lowercase letters are significantly different (P < 0.05)