Quick Answer. A lightning arrester protects telecommunication and electrical power systems from damage during a lightning strike. It accomplishes this by redirecting the current in the lightning to the ground.
Bloating, burping and passing gas are natural and are usually caused by swallowed air or the breakdown of food through digestion.
Burping is generally caused by swallowing air when eating or drinking and subsequently expelling it, so in this case the expelled gas is mainly a mixture of nitrogen and oxygen.