Human activities have released significant quantities of carbon dioxide into the atmosphere. As a greenhouse gas, the more carbon dioxide emitted, the warmer our planet becomes. Partly mitigating these impacts, plants recover 30% of atmospheric carbon via photosynthesis. Using energy from the Sun, they combine carbon dioxide with water to form sugar and oxygen. When the chemical reaction is reversed, carbon returns to the atmosphere – either by cellular respiration in plants and animals, or the burning of coal, wood, or gasoline. Soil scientist Dr Samantha Grover explains that one way of preventing carbon dioxide from returning to the atmosphere is keeping it sequestered in the ground. In fact, there is two-to-three times more carbon in soil than in the atmosphere.