Photosynthetic plants use carbon dioxide to generate and function. Plants need energy (glucose) to survive. They exist to absorb carbon dioxide from the atmosphere. One of their end products is oxygen. Animals take in oxygen and release carbon dioxide while the plants take in carbon dioxide and release oxygen. This is balance.
If a person built a bridge that didn’t have water holes under it than the other side of the river would drought and kill all animals depending on that sorce of water
