A Simple Litter System
- Author: O.Conrad (c) 2003
- Menu: Simulation | Ecology | Modelling the Human Impact on Nature
Description
A simple numerical litter system model demonstrating the usage of the Euler method. Litter carbon storage (C) is calculated in dependency of litter fall rate (Cinput) and rate constant for litter loss (Closs) as:
- C(t + 1) = C(t) + (Cinput - Closs * C(t)) * dt
Typical values:
| Tropical Rainforest | Temperate forest | Boreal forest |
|---|
| Litter fall rate [g/m2/yr] | 500 | 240 | 50 |
|---|
| Litter loss rate [1/yr] | 2.0 | 0.4 | 0.05 |
|---|
References
- Hugget, R.J. (1993): Modelling the Human Impact on Nature. Oxford University Press.
Parameters
| | Name | Type | Identifier | Description | Constraints |
|---|
| Output | Litter | table, output | TABLE | - | - |
| Options | Time Span | floating point number | TIME_SPAN | [yrs] | Minimum: 0.000000
Default: 50.000000 |
| Time Interval | floating point number | TIME_STEP | [yrs] | Minimum: 0.000000
Default: 0.100000 |
| Initial Litter Storage | floating point number | C_INIT | [g/m2] | Minimum: 0.000000
Default: 0.000000 |
| Presets | choice | PRESETS | - | Available Choices:
[0] Tropical forest
[1] Temperate forest
[2] Boreal forest
[3] Adjust parameters manually
Default: 3 |
| Litterfall Rate | floating point number | C_INPUT | [g/m2/yr] | Minimum: 0.000000
Default: 240.000000 |
| Rate Constant for Litter Loss | floating point number | C_OUTPUT | [1/yr] | Minimum: 0.000000
Default: 0.400000 |
Command Line
Usage: saga_cmd sim_ecosystems_hugget 0 [-TABLE ] [-TIME_SPAN ] [-TIME_STEP ] [-C_INIT ] [-PRESETS ] [-C_INPUT ] [-C_OUTPUT ]
-TABLE: Litter
table, output
-TIME_SPAN: Time Span
floating point number
Minimum: 0.000000
Default: 50.000000
-TIME_STEP: Time Interval
floating point number
Minimum: 0.000000
Default: 0.100000
-C_INIT: Initial Litter Storage
floating point number
Minimum: 0.000000
Default: 0.000000
-PRESETS: Presets
choice
Available Choices:
[0] Tropical forest
[1] Temperate forest
[2] Boreal forest
[3] Adjust parameters manually
Default: 3
-C_INPUT: Litterfall Rate
floating point number
Minimum: 0.000000
Default: 240.000000
-C_OUTPUT: Rate Constant for Litter Loss
floating point number
Minimum: 0.000000
Default: 0.400000