More information: Yunyu Zhang et al, Exchangeable manganese regulates carbon storage in the humus layer of the boreal forest, Proceedings of the National Academy of Sciences (2024). DOI ...
l), our knowledge of the turn-over of forest soil humus is very incomplete. This is particularly true of the organic matter in soil horizons below the humus layer.
For example, FoxFarm Ocean Forest potting soil contains aged forest humus, sphagnum peat moss, sandy loam, perlite, granite dust, oyster shell, earthworm castings, bat guano, crab meal ...