When you denude something, you expose it by taking away what covers or protects it. Loggers who clearcut forests denude them of all trees.
There are both natural and human-related ways to denude a piece of land or an area of the earth's surface. The erosion of sea water on the coast can denude beaches and coastlines, eroding and wearing them away. Pesticides used on large farms can denude entire regions of honey bees. The word comes from a Latin root, denudare, "to lay bare, strip, or expose," from de-, "away," and nudare, "to strip."