The Impacts of Climatic Change on Water Quality and Nile Tilapia (Oreochromis niloticus) in Burullus Lake, Egypt.

Abstract

L ake Burullus is the second largest one that is located in the Nile Delta and is connected to the Mediterranean by a narrow outlet. This Lake faces various anthropogenic-induced implications that threat its ecosystem and biodiversity. The prime objective of this study is investigating the impacts of climate change and seasonal variation on water quality and Nile Tilapia fish (Oreochromis niloticus) of Lake Burullus, during 2022. Five stations: (1) El-Burullus drain; (2) Bougaz El-Burullus; (3) Drain ( 7); (4) El-Shakhloba and (5) Mastrou were studied. Surface water samples were collected for assessment water quality from these stations during Four seasons. Also, fish serum and muscles samples were collected for biochemical parameters. Results showed the physicochemical criteria of water quality were attributed with seasonal variation. Salinity % of Lake water was the highest during Winter and Spring seasons especially at Bougaz El-Burullus. Dissolved oxygen (DO) and ammonia (NH3) were significantly increased during Summer and Autumn. The study showed seasonal changes in the level of total protein, albumin, globulin, AST, ALT in serum of Tilapia fish. These biochemical markers were significantly increased during summer. Besides, Muscles total protein, total lipids and glycogen content were significantly decreased during Summer comparing with other seasons.In conclusion, Lake Burullus water quality, serum biochemical markers and muscles content of Nile Tilapia fish are affected by climatic changes during seasonal variation and environmental stress particularly at the discharge points which must be monitored and controlled.