| 1
Model identification |
Soil
Erosion Network - Model |
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1.1
Model name |
MEDALUS
-Water ersosion |
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1.2
Most recent version |
1.0 |
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1.3
Date of release |
December
1994 |
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| 2
Water erosion |
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| 3
Contact person |
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3.1
Name |
Mike
Kirkby |
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3.2
Address |
School
of Geography, University of Leeds, Leeds LS2 9JT |
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3.3
Tel |
+44
113 233 3310 |
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3.4
Fax |
+44
113 233 6758 |
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3.5
Email |
mike@geog.leeds.ac.uk
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|
| 4
Model Author(s) |
M
D McMahon, M J Kirkby, J B Thornes, F I Woodward |
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| 5
Model components |
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5.1
Water erosion: |
Water
and sediment routed over rough surface |
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5.2
Wind erosion: |
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5.3
Hydrology: |
Richards
equation for soil: Infiltration into rough, vegetated surface |
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5.4
Site/topography: |
Hillslope
catena from field data |
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5.5
Plant growth: |
Models
for uncultivated annuals, grass and shrubs |
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5.6
Management: |
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5.7
Soil: |
Dynamic
change with erosion in armour and composition |
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5.8
Chemistry: |
Organic
soil component using C budget |
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5.9
Weather: |
Automatic
Weather station data (5-15 minute) |
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| 6
Model characteristics |
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6.1
Spatial |
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6.1.1
Class of area: |
Slope
catena/small catchment |
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6.1.2
Flow routing system: |
Grid |
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|
6.1.3
Minimum area: |
Erosion
plot |
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|
6.1.4
Maximum area: |
10
Ha |
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6.2.
Temporal |
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6.2.1
Timestep: |
5-15
minute |
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6.2.2
Single or multiple event? |
Multiple |
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|
6.2.3
Maximum simulation duration: |
100
years |
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| 7
Model's representation of processes |
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7.1
Water erosion processes |
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7.1.1
Interrill: |
Included
in spectrum of surface roughness |
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7.1.2
Rill: |
Included
in spectrum of surface roughness |
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7.1.3
Gully: |
Included
in spectrum of surface roughness |
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7.1.4
Streambank: |
- |
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|
7.1.5
Deposition: |
Included
in integrated sediment routing |
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7.2
Wind erosion processes: |
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7.2.1
Creep/surface roll: |
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7.2.2
Saltation: |
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7.2.3
Suspension |
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7.3
Hydrological processes: |
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7.3.1
Evaporation/transpiration: |
Modified
Penman, allowing for soil layers, plant stress, etc. |
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7.3.2
Runoff: |
Overland
flow routing over rough micro-topography |
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|
7.3.3
Infiltration |
Spatially
variable using Richards equation for ponded and non-ponded areas |
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|
7.3.4
Subsurface flow: |
Lateral
component of Richards equation |
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|
7.3.5
Return flow |
Arises
from solution of equations in principle |
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7.4
Plant processes: |
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7.4.1
Light interception and photsynthesis: |
Beer's
Law |
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7.4.2
Dry matter and residue |
Based
on photosynthesis and transpiration; respiration; leaf fall,
etc. |
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7.4.3
Root growth: |
Functional-group
based partition of net growth with stems |
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7.4.4
Pests: |
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7.4.5
CO2 sensitivity: |
Implicit
in water stress photosynthesis calculations |
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7.5
Soil: |
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7.5.1
Crust development |
Not
modelled for stony soils |
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7.5.2
Aggregate properties |
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7.6
Chemistry: |
Only
for carbon |
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7.6.1
Nutrients: |
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7.6.2
Carbon |
Used
in logging organic soil accumulation, mixing and decomposition |
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7.6.3
Pesticides |
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7.6.4
Other contaminants |
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7.7
Weather: |
Stochastic
generator used for future scenarios |
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7.8
Other: |
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| 8
Input Data (* = Mandatory) |
|
8.1
Weather: |
5-15
minute interval (or stochastic generator) for precipitation*,
temperature*, net radiation*, humidity*, wind speed* (AWS data).
Grain sizes with depth*, including stoniness |
|
8.2
Soil: |
|
|
8.3
Hydrology: |
Moisture
retention curve*(s) |
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8.4
Plant cover: |
%
shrub*, grass*, annuals* and bare*, with detail as available |
|
8.5
Soil surface cover: |
Surface
stoniness*, vegetation crown cover by functional; type* |
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8.6
Management: |
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|
8.7
Topography/site characteristics: = |
Slope
profile |
|
8.8
Micro-topography: |
RMS
roughness* at several* points down slope profile |
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8.9
Other |
Physiological
characteristics of dominant plants in each functional group |
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| 9
Output data |
Runoff,
soil moisture profiles, sediment transport and net erosion/deposition
down length of slope, integrated over selected time intervals.
Vegetation and organic soil biomass, surface roughness and armour
characteristics over time |
|
| 10
Programming language |
Turbo
Pascal (V6.0) |
|
| 11
Computer requirements |
IBM
PC compatibles, preferably a fast 486/586 and minimally a 386DX |
|
| 12
Documentation |
|
12.1
Scientific documentation: |
Kirkby,
M.J., Baird, A.J., Lockwood, J.G., McMahon, M.D., Mitchell,
P.J., Shao, J., Sheehy, J.E., Thornes J.B. and Woodward, F.I.
1993. MEDALUS Project A1: Physically based process models: Final
report (part of MEDALUS I final report, edited J B Thornes). |
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12.2
User's guide: |
Not
yet available |
|
12.3
Technical documentation: |
Available
on request from author (McMahon) |
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| 13
Availability |
Available
on request from authors |
| 14
Other Relevant Information |
Currently
still undergoing testing, but available in trial form for experimental
use. |
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