The carboniferous became massive amounts of coal.

Coal FORESTS covered much of the Earth’s tropical land area during Carboniferous times. During those times, the vegetable matter decayed on the carboniferous forests and accumulated a huge deposit of peat that later changed into coal. Aside from the Carboniferous era, this event also happened during the Permian times.

The first means of speeding up reactions mentioned by the speaker is raising the enzymes