Please enable JavaScript.
Coggle requires JavaScript to display documents.
Forest Humus - Coggle Diagram
Forest Humus
Humus Qualities
Importance
Source of nutrients
Aeration of soils
Adds porosity
Protection from soil erosion
Soil development
Additions
Translocations
Soil Insulation
Natural mulch
Protects soil surface from raindrop impact and soil erosion
Insulates underlying soil
Promotes regeneration of certain species
Mor Humus Form
Found under coniferous forests
Acidic soils (lower PH)
Abundance of roots, fungal celia and needle leaves
Large L layer
Binds the F and H horizons together
Difficult to pull apart
peels off from the top soil like a carpet
Slow decomposition of coniferous needles
High C/N ratio
Low nutrient contents
High carbon
Combined F and H horizons
higher than a centimeter
F horizon is matted with fungal mycelia
Decomposition primarily by fungi
mycogenous fungal layer
Mull Humus Form
F and H layers thin or absent
Organic enriched mineral soil
(Ah) layer
Ah layer can be very large
depending on amount of soil mixing
Lower relative C:N ratio;
faster decomposition rates
High amount of Nitrogen
Good amount of nutrients
Common in grassland environments
Neutral soil pH
Many organisms present
Good habitat for earthworms
and other bioturbators
BCIT soil pit example of
mull humus form
Moder Humus Form
Zoological Fz, or Fa layer diagnostic
Neutral pH
Good environment for earthworms
and other bioturbators
Presence of fungus and insects
Common is deciduous forests
If alder trees present
good source for Nitrogen
Looser arrangement of layers.
Doesn't peel back like Mor
Moderate decomposition rates
Gradual boundary between organic and mineral soil