How well does soil actually store carbon?

Measurement

The complexities of measuring soil carbon are significant, as Eric Slessarev explains. He highlights the challenge of determining additional carbon sequestration, emphasizing that the real issue is understanding what would have happened on the land without intervention 1. This uncertainty complicates the measurement process, which requires extensive sampling to get accurate results. Slessarev notes, "It's still not clear exactly how deep we should be going, although it's probably deeper than 30 cm, which is the kind of minimum that people require" 2. The need for more precise measurement techniques is evident, as current methods are not fully reliable.

   

Additionality

Additionality is a critical factor in soil carbon sequestration projects. Eric Slessarev points out that many agricultural practices, like cover cropping and no-till farming, were initially developed for reasons unrelated to carbon sequestration 3. The challenge lies in determining how much additional carbon is sequestered due to these practices, which is essential for carbon credits. Slessarev states, "If somebody was going to be practicing no till agriculture, regardless of whether you paid them for it, then it doesn't count as carbon removal" 1. This highlights the complexity of assessing true additionality in carbon credits.