Alkatrani, L. 2025. An Assessment of marine fish species diversity in the Shatt Al-Arab River and Al-Hammar Marsh: a comparative study before and during salt intrusion: Marine fish assemblage in Shatt alArab River and AlHammar Marsh before and after salinity inturusion. Mesopotamia Environmental Journal (mesop. environ. j) ISSN: 2410-2598. 8, 2 (Jan. 2025), 17–34.