1.identify the 2 major reservoirs of carbon dioxide into the atmosphere

2.what are the forms in which carbonis found n the oceans

Since this is not my area of expertise, I searched Google under the key words "carbon dioxide reservoirs atmosphere" to get these possible sources:

http://www.planetguide.net/cool/carboncycle_activity.html
(Broken Link Removed)
http://en.wikipedia.org/wiki/Carbon_cycle
http://www.sprl.umich.edu/SPRL/Report/1995/31_AtmosEvolution.html
http://www.safeclimate.net/business/understanding/carboncycle.php

I hope this helps. Thanks for asking.