Module 01: A Simple Litter System
A simple litter system model using the euler method. 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:
-- Litter fall rate: 500 [g/m2/a]
-- Litter loss rate: 2.0 [1/a]
- Temperate forest:
-- Litter fall rate: 240 [g/m2/a]
-- Litter loss rate: 0.4 [1/a]
- Boreal forest:
-- Litter fall rate: 50 [g/m2/a]
-- Litter loss rate: 0.05 [1/a]
Reference:
Hugget, R.J. (1993): 'Modelling the Human Impact on Nature', Oxford University Press.
- Author: (c) 2003 by O.Conrad
- Specification: grid
- Menu: Simulation|Ecology|Modelling the Human Impact on Nature
Parameters
| Name | Type | Identifier | Description | Constraints |
Output | Results | Table (output) | TABLE | - | - |
Options | Time Span | Floating point | TIME_SPAN | - | Minimum: 0.000000 Default: 100.000000 |
Time Interval [a] | Floating point | TIME_STEP | - | Minimum: 0.000000 Default: 0.100000 |
Initial Litter Storage [g/m²] | Floating point | C_INIT | - | Minimum: 0.000000 Default: 0.000000 |
Litterfall Rate [g/m²/a] | Floating point | C_INPUT | - | Minimum: 0.000000 Default: 240.000000 |
Rate Constant for Litter Loss [1/a] | Floating point | C_OUTPUT | - | Minimum: 0.000000 Default: 0.400000 |
Command-line
Usage: saga_cmd sim_ecosystems_hugget 0 [-TABLE <str>] [-TIME_SPAN <str>] [-TIME_STEP <str>] [-C_INIT <str>] [-C_INPUT <str>] [-C_OUTPUT <str>]
-TABLE:<str> Results
Table (output)
-TIME_SPAN:<str> Time Span
Floating point
Minimum: 0.000000
Default: 100.000000
-TIME_STEP:<str> Time Interval [a]
Floating point
Minimum: 0.000000
Default: 0.100000
-C_INIT:<str> Initial Litter Storage [g/m2]
Floating point
Minimum: 0.000000
Default: 0.000000
-C_INPUT:<str> Litterfall Rate [g/m2/a]
Floating point
Minimum: 0.000000
Default: 240.000000
-C_OUTPUT:<str> Rate Constant for Litter Loss [1/a]
Floating point
Minimum: 0.000000
Default: 0.400000