sorption vs natural action

sorption and natural action both are nouns.

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

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

sorption: the process in which one substance takes up or holds another (by either absorption or adsorption)
natural action: a process existing in or produced by nature (rather than by the intent of human beings)

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

sorption (noun)	natural action (noun)
the process in which one substance takes up or holds another (by either absorption or adsorption)	a process existing in or produced by nature (rather than by the intent of human beings)