1. Gersmehl Diagrams

2. The Soil The soil is a mixture of
Decomposing organic material (from dead animals and plants, leaf litter, etc.
Tiny rock particles being eroded from the earth
Water
Air spaces

3. Biomass Biomass is the mass of living organisms.
All the species of an ecosystem contribute to its biomass.

4. Litter
At any time there are dead animals or fallen parts of plants being decomposed on the ground.
They have not yet become humus in the soil.
This makes up the ‘litter’.

5. Arrows
There is a constant transfer of nutrients between each of the three stores, soil, litter and biomass.
The arrows show the size of the transfer.

6. Decomposition
Where there is fast decomposition of little there will be a smaller amount of litter.
Where decomposition happens slowly there will be more litter on the surface of the soil

7. Temperature and Precipitation
As the temperature rise and the precipitation rises the amount of biomass increase. The uptake of minerals from the soil increases.