It's fused into natural mixes by autotrophs and enters the dirt when living beings die.
I believe it is the Nitrogen cycle although all of the cycles use bacteria. Only nitrogen requires nitrogen fixing bacteria to keep the cycle going.
We've had the same amount of water on our planet since the beginning of time. Even though 70 percent of the globe is covered in water, less than 1 percent is accessible to us.
But now there is 6.7 billion people using that water. We're on track to be up to 8 billion people in 15 years. With our current population, there is already water stress.
