Preservationist

Preservationist is generally understood to mean historic preservationist: one who advocates to preserve architecturally or historically significant buildings, structures, objects, or sites from demolition or degradation. Historic preservation usually refers to the preservation of the built environment, not to the preservation of, for instance, primeval forests or wilderness.^[1]

Preservationist is, however, sometimes used descriptively in other contexts, notably with regards to language and the environment.