Low-salinity events caused by heavy rainfall and freshwater runoff pose significant environmental constraints on eucheumatoid seaweed mariculture in coastal areas. In this study, five eucheumatoid seaweeds, including three strains of Kappaphycus alvarezii (Hn-R, Hn-G, and Ma-R), Kappaphycus striatum, and Eucheuma denticulatum, were exposed to 22, 26, and 30 psu for 36 days. Growth performance, photosynthetic pigments, chloroph...