Gordon Hempton, a sound recordist and acoustic ecologist from Washington state, has been campaigning for the preservation of natural silence, which “is as necessary and essential as species preservation, habitat restoration, toxic waste cleanup, and carbon dioxide reduction.” He claims that there are very few remaining quiet places in the United States, even though the country has large tracts of empty land. True freedom from artificial sounds is surprisingly hard to achieve because of the web of flight paths that crisscross the sky.
Singing sand dunes
biophony to refer to sounds of living organisms, and geophony to refer to (as I understand it) natural but non-animal sounds, like waves crashing on a beach or wind in the trees.