Original: The approximately halocline between the seawater above and brine below teems with bacterial and archaeal cells: they are chemoautotrophs, which feed on ammonia from the brine but can not function without some oxygen.
Simplified: This halocline between the seawater above and the brine below has many bacterial and archaeal cells: they are chemoautotrophs, which feed on ammonia from the brine but can not function without some oxygen.