Surrounding (7)
There are a few possibilities for this:
boxing-in
'surrounding' is the definition.
(synonyms)
This is the entire clue.
(Other definitions for ambient that I've seen before include "Bait men to find surrounding, say, light" , "Relating to the immediate surroundings" , "Relating to the immediate environment" , "Of music, say, played at low volume to create atmosphere" , "Surrounding - mean bit (anag)" .)
'surrounding' is the definition.
('ring' can be a synonym of 'surround')
This is all the clue.
(Other definitions for ringing that I've seen before include "Having resonant sound" , "Chiming" , "Campanology" , "Resonant; forceful" , "Telephoning" .)