This is when bacteria in the soil convert the nitrate back into nitrogen gas which then gets released back into the atmosphere.

Nitrogen is one of the primary nutrients critical for the survival of all living organisms. Although nitrogen is very abundant in the atmosphere, it is largely inaccessible in this form to most ...

Figure 1: Specific cell associations that define the stages of the cycle of the seminiferous epithelium ... Freeze the pooled tubules in liquid nitrogen and transfer to −80 °C for long-term ...