The Earth's Natural Reaction to CO2

It's always been a well-known fact that if the number of natural predators of an animal decrease, the population of that animal will increase. Then because of the abundance of the first animal the predators will increase until an equilibrium is reached.This is the first time I've seen any study of equilibrium on a global scale. (Link) An increase in the amount of CO2 in the air causes more plants to grow, which may in turn balance out the level of CO2.