1. Nitrogen Fixation: Nitrogen-fixing bacteria (like *Rhizobium* and *Azotobacter*) convert atmospheric nitrogen gas (N2) into usable forms, primarily ammonia (NH3), which plants can absorb. This is the crucial first step in the nitrogen cycle, making nitrogen available to living organisms.
2. Nitrification: Nitrifying bacteria (like *Nitrosomonas* and *Nitrobacter*) oxidize ammonia (NH3) into nitrite (NO2-) and then into nitrate (NO3-). This process is essential for making nitrogen available to plants in a form they can easily absorb.
3. Denitrification: Denitrifying bacteria (like *Pseudomonas* and *Clostridium*) convert nitrate (NO3-) back into nitrogen gas (N2), which is released into the atmosphere. This process completes the cycle and regulates the amount of nitrogen available in the ecosystem.
Let me know if you'd like more detail on any of these processes!
