Below you can find the About 80% of this gas in the air comes from decomposition in rice paddies swamps & animal intestines Jeopardy Words Answer. The answer to About 80% of this gas in the air comes from decomposition in rice paddies swamps & animal intestines has 7 letters. This clue belongs to the The air up there category and is part of Jeopardy Word Level 306. If you scroll near the bottom you will find other clues and answers part of level 306