acidification vs natural action

acidification and natural action both are nouns.

Word	Noun	Adjective	Verb	Adverb
acidification	Yes	No	No	No
natural action	Yes	No	No	No

As nouns, natural action is a hypernym of acidification; that is, natural action is a word with a broader meaning than acidification:

acidification: the process of becoming acid or being converted into an acid
natural action: a process existing in or produced by nature (rather than by the intent of human beings)

Other hypernyms of acidification include action, activity, natural process.

acidification (noun)	natural action (noun)
the process of becoming acid or being converted into an acid	a process existing in or produced by nature (rather than by the intent of human beings)