Runoff and sediment load were simulated using the combination of disturbed DEMs and NLCDs. For the sake of efficiency in analysis, the 100 realizations for each DEM and NLCD were combined one-to-one to create 100 realizations that have errors in both DEM and NLCD. As seen in Table 5, the runoff and sediment load simulated with the disturbed DEM and NLCD are not greatly different from those of the disturbed DEM alone. The patterns of the discrepancy between the simulated runoff and sediment load and the variation statistics are also very close to each other. The implication is that the impact of the DEM error on the runoff and sediment load simulation is much greater than that of the NLCD error. In addition, as seen in Figure 9, the slopes and coefficients of determination (R2) of the linear regression equations are close to one, meaning the simulated errors of the GIS layers do not significantly influence the runoff and sediment transport simulation.
Table 5

Statistics of variations in the monthly runoff and sediment load simulated with the disturbed DEMs and NLCDs

Runoff
Sediment load
Dataset with errorStatisticsm3/s%Mg%
DEM Max range 29.3 80.3 64.6 170.0 
Ave. range 3.28 9.0 7.40 19.6 
Max CI 2.84 7.8 4.99 13.2 
Ave. CI 0.28 0.8 0.61 1.6 
NLCD Max range 17.0 46.7 47.0 124.4 
Ave. range 1.83 5.0 5.78 15.3 
Max. CI 1.03 2.8 3.96 10.5 
Ave. CI 0.14 0.4 0.45 1.2 
DEM/NLCD Max range 30.7 84.1 75.2 199.1 
Ave. range 3.49 9.6 8.60 22.8 
Max. CI 2.77 7.6 6.47 17.1 
Ave. CI 0.29 0.8 0.72 1.9 
Average runoff rate and sediment loada 36.5 100.0 37.8 100.0 
Runoff
Sediment load
Dataset with errorStatisticsm3/s%Mg%
DEM Max range 29.3 80.3 64.6 170.0 
Ave. range 3.28 9.0 7.40 19.6 
Max CI 2.84 7.8 4.99 13.2 
Ave. CI 0.28 0.8 0.61 1.6 
NLCD Max range 17.0 46.7 47.0 124.4 
Ave. range 1.83 5.0 5.78 15.3 
Max. CI 1.03 2.8 3.96 10.5 
Ave. CI 0.14 0.4 0.45 1.2 
DEM/NLCD Max range 30.7 84.1 75.2 199.1 
Ave. range 3.49 9.6 8.60 22.8 
Max. CI 2.77 7.6 6.47 17.1 
Ave. CI 0.29 0.8 0.72 1.9 
Average runoff rate and sediment loada 36.5 100.0 37.8 100.0 

aThese values, 36.5 m3/s and 37.7 Mg, were calculated by averaging monthly runoff rates and sediment loads simulated with the original DEM and NLCD using a calibrated HYSTAR model.

View Large
Figure 9
Figure 9. Agreement of the average monthly runoff (m3/s) and sediment load (Mg) for the original and the disturbed DEM and NLCDs. Monthly runoff and sediment loads were simulated with the 100 disturbed DEMs, the 100 disturbed NLCDs, and their one-to-one combinations, and then each 100 simulated runoff and sediment loads were averaged.
View largeDownload slide

Agreement of the average monthly runoff (m3/s) and sediment load (Mg) for the original and the disturbed DEM and NLCDs. Monthly runoff and sediment loads were simulated with the 100 disturbed DEMs, the 100 disturbed NLCDs, and their one-to-one combinations, and then each 100 simulated runoff and sediment loads were averaged.

Figure 9
Figure 9. Agreement of the average monthly runoff (m3/s) and sediment load (Mg) for the original and the disturbed DEM and NLCDs. Monthly runoff and sediment loads were simulated with the 100 disturbed DEMs, the 100 disturbed NLCDs, and their one-to-one combinations, and then each 100 simulated runoff and sediment loads were averaged.
View largeDownload slide

Agreement of the average monthly runoff (m3/s) and sediment load (Mg) for the original and the disturbed DEM and NLCDs. Monthly runoff and sediment loads were simulated with the 100 disturbed DEMs, the 100 disturbed NLCDs, and their one-to-one combinations, and then each 100 simulated runoff and sediment loads were averaged.

Close modal
Close Modal
This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal
This site uses cookies. By continuing to use our website, you are agreeing to our privacy policy.
Accept