Another connection between the biosphere-atmosphere cycle and the rock cycle is through the production of plant tissue by the conversion of CO2 to carbon compounds using sunlight as an energy source. Plant matter that escapes being eaten, escapes to the oceans where it can be buried. Again, plants take CO2 from the atmosphere and deliver it to sediments in the sea. The rock cycle and the lithosphere plate cycle are intimately connected, because, it is the latter which delivers material that was dumped out in the oceans back up to the surface where it can again be weathered. This happens either by the creation of mountain belts by the collision of the continental parts of plates, or by subduction which results in the melting of a plate with concomitant volcanism.
Volcanism connects the lithosphere plate cycle with the biosphere-atmosphere cycle.
Volcanism due both to subduction and the creation of new oceanic crust at spreading centers results in the release of CO2 into the atmosphere, completing the cycle of carbon. It takes on average 60,000,000 years for carbon to get from plants to sediments in the oceans and back out into the atmosphere again. This is a very important control on the CO2 on the atmosphere and it seems independent of life, and is presumably controlled by processes deep within the earth. The products of this mechanical weathering can be broken down more quickly by weathering by plant roots than solid rock. Therefore times of mountain building should be times of greater loss of CO2 from the atmosphere and greater limestone deposition in the oceans.