Although bacteria are too small to be seen with the naked eye, they do play a key role in breaking down dead branches and leaves. They can break down tree trunks and branches that absorb carbon dioxide and other nutrients and release them into the atmosphere. Without bacteria, the earth's carbon dioxide can only be used by plants for 40 years, because carbon will be locked in plants and will not be involved in the material cycle. Because of this effect of bacteria, it maintains the green color of the whole forest and even the whole earth.
incorrect in interpreting key rolein the text?
In the process of decomposing tree trunks and branches and leaves, bacteria release the carbon dioxide it absorbs into the atmosphere