While nitrogen is an essential nutrient, its availability is naturally limited, making it an important factor in regulating the structure and functioning of both terrestrial and aquatic ecological systems.
The structure and functioning of terrestrial and aquatic ecological systems are regulated by nitrogen.
Nitrogen is not an essential nutrient.
A nice sunny day outside.
There were staff in white coats who had test-tubes.
There is no meaning any of it.
Businesses took advantage me too.
You can tie your boat in a protected area.
Kurdish teaching is permitted.