Thank you for your comments.
The UN conducted this original study, and there have some more recent studies that suggest that the livestock contribution is even higher. It's not the CO2 as much as the methane emitted by the cattle and body waste that is the main problem, since methane is 23 times more toxic as a greenhouse gas (GHG) than carbon dioxide.
There isn't any appreciable methane emitted form growing plants.
In the Love of the Lord,
Frank and Mary