Tool A Simple Litter System
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.
- Author: O.Conrad (c) 2003
- Menu: Simulation|Ecology|Modelling the Human Impact on Nature
Parameters
| Name | Type | Identifier | Description | Constraints | |
|---|---|---|---|---|---|
| Output | Litter | Table, output | TABLE | - | - |
| Options | Time Span | Floating point | TIME_SPAN | [yrs] | Minimum: 0.000000 Default: 50.000000 |
| Time Interval | Floating point | TIME_STEP | [yrs] | Minimum: 0.000000 Default: 0.100000 | |
| Initial Litter Storage | Floating point | 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 | C_INPUT | [g/m2/yr] | Minimum: 0.000000 Default: 240.000000 | |
| Rate Constant for Litter Loss | Floating point | C_OUTPUT | [1/yr] | Minimum: 0.000000 Default: 0.400000 |
Command-line
Usage: saga_cmd sim_ecosystems_hugget 0 [-TABLE <str>] [-TIME_SPAN <double>] [-TIME_STEP <double>] [-C_INIT <double>] [-PRESETS <str>] [-C_INPUT <double>] [-C_OUTPUT <double>] -TABLE:<str> Litter Table, output -TIME_SPAN:<double> Time Span Floating point Minimum: 0.000000 Default: 50.000000 -TIME_STEP:<double> Time Interval Floating point Minimum: 0.000000 Default: 0.100000 -C_INIT:<double> Initial Litter Storage Floating point Minimum: 0.000000 Default: 0.000000 -PRESETS:<str> Presets Choice Available Choices: [0] Tropical forest [1] Temperate forest [2] Boreal forest [3] Adjust parameters manually Default: 3 -C_INPUT:<double> Litterfall Rate Floating point Minimum: 0.000000 Default: 240.000000 -C_OUTPUT:<double> Rate Constant for Litter Loss Floating point Minimum: 0.000000 Default: 0.400000