Mineralization of soil organic matter from equatorial giant podzols submitted to drier pedoclimate: A drainage topochronosequence study

•Active hydromorphic podzol in the area store around 63 kgC m−2.•Erosive incision by a river meander resulted in air entry and oxygenation of the Bh.•C content in the Bh of a podzol truncated due to meander diminished by 70%.•Drier climate would induce C emission from Amazonian podzol Bhs.