The absence of the article, the so-called "zero-article", can be used to refer to the noun in general as mode or manner:
Some plants grow on land while others are aquatic and grow in water.
The article "the" can cast the noun it specifies as something everyone knows about, something ubiquitous, not as a particular instance:
We must not speak loudly in the library.
In the city, children often play in the street.
Some plants grow on the land and others in the water.
And the plural can refer to the noun generally:
Airplanes have monitors that warn pilots to pull up when flying too low over mountains.