nitrogen cycling

Nitrogen cycling is the natural process of nitrogen moving between the atmosphere, soil, water, and living organisms. Nitrogen gas (N2) in the air is converted into a usable form by bacteria in the soil—a process called nitrogen fixation. Plants absorb this nitrogen, which then enters the food chain as animals eat the plants. When organisms die or excrete waste, nitrogen returns to the soil. Specialized bacteria then convert it back into nitrogen gas, completing the cycle. This process is crucial for maintaining healthy ecosystems, as nitrogen is a key component of proteins and DNA essential for life.