soil erosion vs eroding

soil erosion and eroding both are nouns.

Word	Noun	Adjective	Verb	Adverb
soil erosion	Yes	No	No	No
eroding	Yes	No	No	No

As nouns, eroding is a hypernym of soil erosion; that is, eroding is a word with a broader meaning than soil erosion:

soil erosion: the washing away of soil by the flow of water
eroding: (geology) the mechanical process of wearing or grinding something down (as by particles washing over it), also figuratively

Other hypernyms of soil erosion include eating away, erosion, wearing, wearing away.

soil erosion (noun)	eroding (noun)
the washing away of soil by the flow of water	(geology) the mechanical process of wearing or grinding something down (as by particles washing over it), also figuratively