Can intra-aggregate pore structures affect the aggregate's effectiveness in protecting carbon?

► We measured soil C in aggregate subsections scanned using X-ray computed tomography. ► Total C was negatively correlated with presence of medium pores (30-60 μ). ► C was positively correlated with small pores and with biological large pores. ► C was more variable in native vegetation than in plowed agriculture aggregates. ► Plowed soil aggregates are less effective in protecting C than native ones.