There is no clear evidence that livestock grazing can significantly enhance soil carbon stores. And there is significant research that demonstrates greater carbon storage with no grazing. Livestock grazing appears to be a questionable strategy for reducing global atmospheric carbon. Climatic conditions year to year, for instance, can shift carbon storage in grazed areas from a positive to a negative. Furthermore, any storage is gradual and takes years to accumulate, while carbon uptake by soils is finite and slows over time. And compared to almost all other ecosystems, arid rangelands are among the least productive ecosystems—hence have little potential for soil carbon storage compared to other ecosystems like forests.
One cannot look at the soil carbon storage issue out of context. Livestock are among the greatest source of GHG emissions now—and reducing livestock numbers is the quickest and perhaps the most effective means of significantly altering GHG emissions. Furthermore, there are a host of collateral damages created by livestock production, from the destruction of soil biocrusts, killing of predators, water pollution, clearing of forests for pasture, and so on.