Plant litter material with a low to very low CN ratio and soil reaction slight acid to alkaline and short term aeration phases will lead to a high degree of decomposition and humusfication. Remains of plat litter are not cognisable.
- Hhn horizon is present as topsoil and
- predominantly anaerobic conditions interupted by short aerobic conditions and
- in many cases oxygen content of groundwater ore spring water ist high and
- Vegetation of natural fen is present
Subtypes
HHM – Mesotrophic H Moor
Soil reaction slight acid to subneutral.
- C/N of the Hhn horizon 20 – < 33 and
- Vegetation of natural fen is present
HHE – Eutrophic H Moor
Soil reaction is slight acid to alkaline.
- C/N of the Hhn horizon 10 – < 20 and
- Vegatation of natural fen is present
HHP – Polytrophic H Moor
Soil reaction neutral to alkaline.
- C/N of the Hhn horizon < 10 and
- Vegetation of natural fen – primarily nitrophilous species – are present and
- peat is enriched by eutrophic or hypertrophic polluted water