| MODEL CALIBRATION AND VALIDATION |
| In this study, LISEM (Limburg Soil Erosion Model) model was evaluated using 6 selected rainstorm events. Three events serve as a calibration set. Rainfall data are available in hourly and outlet discharge. The other three storms serve as a validation set, only rainfall data were used for simulation using calibration parameters (De Roo and Jetten, 1999). |
| The three events were selected to calibrate which includes the 060905(06 September 2005), 180905 (18 September. 2005) and 260905 (26 September 2005) events. Table 6-7 gives a summary of the event characteristic showing that peak discharges were about 37.5, 13.0 and 31.45 m3/s respectively. All events were thus of different magnitude and duration, with the 060905 and 180905 being the least rainfall intensity different. |
| Event |
Event Characteristics |
| Total rainfall(mm) |
Maximum rainfall
intensity (mm/hr) |
Peak discharge (m3/s) |
| Calibration |
| 60905 |
56.00 |
16.00 |
37.50 |
| 180905 |
20.00 |
18.00 |
13.00 |
| 260905 |
32.00 |
30.50 |
31.45 |
| Validation |
| 70905 |
17.50 |
10.00 |
4.20 |
| 90905 |
15.00 |
8.50 |
1.02 |
| 120905 |
29.00 |
20.50 |
15.37 |
|
| The results of the model were compared with discharge data measured from outlet of catchment. The simulated and measured hydrographs for three events are presented in the figure and table. |
| Event |
Rainfall(mm) |
Peak discharge |
| Obs (m3/s) |
Sim (m3/s) |
| Calibration |
| 60905 |
52.58 |
37.5 |
37.90 |
| 180905 |
18.43 |
13.00 |
13.40 |
| 260905 |
29.49 |
31.45 |
32.99 |
| Validation |
| 70905 |
16.60 |
4.2 |
4.72 |
| 90905 |
10.61 |
1.02 |
1.30 |
| 120905 |
26.74 |
15.37 |
23.81 |
|
 |
Figure 1 : Measured and simulated discharge in Nam Chun catchment
of the three calibration and three validation events. |
|
| References |
 De Roo, A.P.J. and Jetten, V.G., 1999. Calibrating and validating the LISEM model for two data sets from the Netherlands and South Africa. CATENA, 37(3-4): 477-493.
http://www.sciencedirect.com/science/article/B6VCG-3Y51V0XH/2/c047330928040c19a8cd581e7540192b |
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