I think that this mechanism is mostly CO2 being slowly weathered out of the atmosphere and disposed of, mostly via limestone formation. This takes a very long time and is very slow, so it can only catch up if you stop pumping it out.
As I recall, there is a group of creatures that may did the first big wave of carbon fixation at the beginning of life, binding CO2 and releasing the important O2 that enabled the appearance of complex life forms, but I can't remember it's name.