In the news article, a researcher says that it’s optimal to have livestock incorporated in the growing system. In veganic agriculture, there are animals incorporated in the growing system, but in the form of free-living microorganisms and wildlife, which create a natural fertility for the soil. See our articles on biodiversity, the soil food web, and the book Teaming with Microbes.
In terms of the carbon impact of veganic agriculture, more carbon is released when the soil is turned. With veganic techniques such as mulches and chipped branch wood, the soil is amended without being tilled.