Plant based foods are not "natural" anymore. At least not the plant based foods which currently can be bought in retail stores.
Here is the thing . In order to grow plant based foods at a large enough scale to make it profitable, farmers need synthetic fertilisers, pesticides, herbicides, fungicides etc.
In the province of Manitoba the biggest CO2 emissions into the atmosphere is coming from the synthetic fertiliser industry. The top CO2 emissions culprit is the production of Synthetic Nitrogen. Now let us get this straight, cows do not need synthetic fertilisers. As a matter of fact cows are producing the fertiliser which our grandparents used to grow healthy gardens which produced nutritious vegetables etc.
If you decide to buy "organic" plant based foods only, then you can be certain that most of the products you buy were grown using "cow" and other animal manure.
And then in a perfect vegan world there would be no cows because farmers will not farm with what is not in demand. And then the plant based farmers will have to rely more and more on synthetic fertilisers.
Also if you eat grain based foods, beans, lentils etc. know for certain that huge tractors, combines etc. were spewing CO2 into the air to till the land, seed, harvest and spraying, herbicides, pesticides, fungicides and fertilizers.
Also tilling of the soil in nature is a catastrophic event! Millions of soil bacteria and beneficial critters like earthworms for instance are getting killed in the process.
Also tilling brings the carbon in the soil to the surface. It gets into contact with Oxygen, oxidation takes place and huge amounts of CO2 are being released into the atmosphere.
By writing this, my aim is not to convince anyone to stop eating plant based foods. Far from it. I myself like to eat bread, beans, lentils, pea soup

, all kinds of vegetables, nuts, fruits and the list can go on. I also eat meat. Everything in moderation though. Just remember eating more meat or less meat will not affect climate change. (When the first settlers arrived on the prairies 60 million buffaloes roamed the prairie grass and did not contribute to climate change!) Meat is not the culprit. Stop eating plant based foods are also not the answer to climate change.
Doing it right, agriculture can sequestrate carbon into the soil. Together farmers and city people can work towards a healthy food supply which will have a neutral carbon footprint. Insist on meat and plant based foods produced by regenerative farmers. (Google Regenerative farming!) The beauty of regenerative farming products is that farmers will have less input costs and therefore will be able to sell their products at a better price to the consumers. With the boon of producing food that is healthier than "certified organic foods"!
In conclusion I would like to admit that there are valid reasons why a person would eat plant based foods only:
1) Your God, religion, church, faith etc. commands you to eat plant based foods only.
2) Taste
3) You do not like the idea that animals have to be slaughtered.
If you would like to know more about regenerative farming and you would like to talk face to face with scientists, take highway ten north of Brandon until you find a MBFI sign on the right hand side, follow the signs and talk to your tax dollar funded scientists about the benefits of regenerative farming.
Let us focus on the real culprit of climate change. Fossil fuels. Do not blame the CO2 emitted into the air when humans and animals breath. There is and always was a carbon cycle.