Without limitation of the definition of "lands" herein, the commissioner may acquire, or approve grants to assist a local unit to acquire:
a. Lands subject to the right of another to occupy the same for a period measured in years or otherwise; or
b. An interest or right consisting, in whole or in part, of a restriction on the use of land by others including owners of other interests therein; such interest or right sometimes known as a "conservation easement."