Bacteria are fundamental components of aquatic ecosystems and play a central role in maintaining productivity by regulating nutrient cycling, organic matter decomposition, and energy flow. They act as primary agents in transforming dissolved and particulate organic matter into forms that are accessible to other organisms, thereby sustaining the base of aquatic food webs and influencing overall ecosystem functioning. One of the most important roles of bacteria in aquatic ecosystems is the decomposition of organic matter. Dead plants, animals, and waste products accumulate continuously in water bodies. Heterotrophic bacteria break down these complex organic materials into simpler compounds through enzymatic processes. During this decomposition, nutrients such as nitrogen, phosphorus, and carbon are mineralized and released into the water as inorganic forms like ammonium, nitrate, and phosphate. These nutrients are essential for the growth of phytoplankton and aquatic plants, which form the primary producers and drive primary productivity. Bacteria