How is nitrogen gas important for aquatic organisms?

Nitrogen gas is crucial for aquatic organisms as it is a key component of amino acids, proteins, and nucleic acids, which are essential for growth and metabolism. While nitrogen gas itself is inert and not directly usable by most organisms, certain bacteria in aquatic environments can convert it into forms like ammonia and nitrates through processes like nitrogen fixation and nitrification. These bioavailable forms of nitrogen are then utilized by plants and phytoplankton, forming the foundation of the aquatic food web. Thus, nitrogen plays a vital role in supporting the overall productivity and health of aquatic ecosystems.