No-till farming alone won’t build soil carbon. Recent research revealed that conservation tillage practices don't have any advantage over conventional practices reported Adele Phillips for the Center for Rural Affairs.
Conservation tillage practices include no-till, chisel plowing, single-disc passes, and more.
The conservation practices were developed because of the dustbowl. Any method that retains crop residue and results in at least 30% of the soil surface being covered after planting is a conservation practice.
More about the recent study is available from the Center for Rural Affairs.