**5. Results and discussion**

Table 1 and Figs. 7 and 8 present the sediment concentration accumulated on bare soil and on soil covered with combined hydroseeding and coconet.


Table 1. Sediment Concentration of Bare Soil and Soil Covered with Combined Hydroseeding and Coconet Reinforcement.

Fig. 6. Artificial Rainfall Simulation Apparatus at the Hydraulic Laboratory of the Flood Control and Sabo Engineering Center (FCSEC) of the Department of Public Works and

Table 1 and Figs. 7 and 8 present the sediment concentration accumulated on bare soil and

TRIAL Time (mins) 0 10 20 30 40 50

Bare Soil 0.000 5.823 20.146 18.553 12.319 9.585

Coconet 0.000 10.740 2.690 2.670 1.060 1.340

Bare Soil 0.000 63.501 39.723 35.130 26.274 21.320

Coconet 0.000 4.990 2.900 4.340 3.330 2.730

Bare Soil 0.000 75.443 68.321 40.743 42.553 33.551

Coconet 0.000 18.970 4.520 2.780 1.500 0.610

Table 1. Sediment Concentration of Bare Soil and Soil Covered with Combined

Highways (DPWH).

TRIAL 1 BOX A

TRIAL 2 BOX B

TRIAL 3 BOX C

**5. Results and discussion** 

Sediment Concentration (g/L)

Hydroseeding with

Hydroseeding with

Hydroseeding with

Hydroseeding and Coconet Reinforcement.

on soil covered with combined hydroseeding and coconet.

Fig. 7. Sediment Concentration (g/L) for Bare Soil

Fig. 8. Sediment Concentration (g/L) for Hydroseeding with Coconet Reinforcemen

It is shown that in each three trial boxes that were first used for bare soil specimen and the vegetated specimen, the first ten (10) minutes deposit higher sediment concentration. But, comparing the values obtained between bare soils and soil with hydroseeding and coconet reinforcement, it shows that as expected there is lower sediment concentration in the latter while higher sediment concentration in the former.

Table 2 and Figs. 9 and 10 present the sediment yield on bare soil and on soil covered with combined hydroseeding and coconet.

Combined Hydroseeding and Coconet Reinforcement for Soil Erosion Control 223

Fig. 10. Sediment Sediment Yield (g/m2h) for Hydroseeding with Coconet Reinforcement As specified, the sediment yield determines the mass of the sediment over its plot area with respect to the time. The results of three trials from Table 2 show that the Hydroseeding with Coconet reinforcement obtained lesser sediment yields than the bare soil, which is already expected since soil without protection from rain splash would deposit greater amount of soil

The proceeding discussion presents the mean sediment concentration and sediment yield

Table 3 and Fig. 11 show the comparison of the mean sediment concentration of Bare Soil and hydroseeding and cocconet Reinforcement. As shown in the table, bare soil accumulates

Time (mins) 0 10 20 30 40 50 Average

Bare Soil 0 48.26 42.73 31.48 27.05 21.49 171.01

Coconet 0 11.57 3.37 3.27 1.97 1.56 3.694

Table 3. Mean Sediment Concentration of Bare Soil and Combination of Hydroseeding with

greater mass of soil sediment than of the hydroseeding and coconet Reinforcement.

for the bare soil and for soil with combined hydroseeding and coconet.

sediments.

Mean Sediment Concentration (g/L)

Hydroseeding with

Coconet Reinforcement


Table 2. Sediment Yield (g/m2h) of Bare Soil and Hydroseeding with Coconet Reinforcement

Fig. 9. Sediment Sediment Yield (g/m2h) for Bare Soil

TRIAL Time (mins) 0 10 20 30 40 50

Bare Soil 0.000 73.873 272.503 225.529 126.809 78.247

with Coconet 0.000 155.330 34.380 18.010 5.650 5.930

Bare Soil 0.000 1533.594 877.431 646.308 356.162 257.866

with Coconet 0.000 49.300 24.870 16.610 9.180 6.020

Bare Soil 0.000 850.000 1169.062 581.067 472.833 227.832

with Coconet 0.000 226.670 83.370 35.430 13.560 5.210

Table 2. Sediment Yield (g/m2h) of Bare Soil and Hydroseeding with Coconet

Sediment Yield (g/m2h)

Hydroseeding

Hydroseeding

Hydroseeding

Fig. 9. Sediment Sediment Yield (g/m2h) for Bare Soil

TRIAL 1 BOX A

TRIAL 2 BOX B

TRIAL 3 BOX C

Reinforcement

Fig. 10. Sediment Sediment Yield (g/m2h) for Hydroseeding with Coconet Reinforcement

As specified, the sediment yield determines the mass of the sediment over its plot area with respect to the time. The results of three trials from Table 2 show that the Hydroseeding with Coconet reinforcement obtained lesser sediment yields than the bare soil, which is already expected since soil without protection from rain splash would deposit greater amount of soil sediments.

The proceeding discussion presents the mean sediment concentration and sediment yield for the bare soil and for soil with combined hydroseeding and coconet.

Table 3 and Fig. 11 show the comparison of the mean sediment concentration of Bare Soil and hydroseeding and cocconet Reinforcement. As shown in the table, bare soil accumulates greater mass of soil sediment than of the hydroseeding and coconet Reinforcement.


yield.

eroded.

Hydroseeding with

Hydroseeding with Coconet versus

Against Soil Erosion (%)

**7. Recommendations** 

**6. Conclusion** 

Combined Hydroseeding and Coconet Reinforcement for Soil Erosion Control 225

The following discussions summarize the total sediment concentration and total sediment

Table 5 compares the sediment concentration and sediment yield of bare soil and hydroseeding with coconet reinforcement. From the numerical value indicated above, it was found out that the Hydroseeding with Coconet reinforcement lessen the mass of the soil

Total Sediment Concentration (g/L) and Sediment Yield (g/m2h) Experiment Sediment Concentration (g/L) Sediment Yield (g/m2h)

Table 6 presents the effectiveness of the applied hydroseeding with coconet reinforcement to control against soil erosion. From the results, it was found out that combined hydroseeding

Effectiveness Of Hydroseeding with Coconet Reinforcement versus Bare Soil Against Soil Erosion (%)

Time (mins) 0 10 20 30 40 50

Bare Soil 0 94.15 97.95 98.4 99.01 98.99

Results of actual laboratory experiments that were conducted with the use of the DPWH Artificial Rainfall Simulation Apparatus showed that the specimen of soil covered with combination of hydroseeding and coconet passed the surface run-off tests. The said specimens did not show any sign of failure in the measurement of run-off in the surface of the slope. Erosion problem was not encountered in the specimen of combined hydroseeding with coconet. The primary effect is that water is absorbed by the hydroseeding materials as

The experiment conducted was limited only for a fixed slope of 65 degrees. The hydroseeding mix had a single set of mixture components. Rainfall simulation rate was at a constant 120mm/hr. Future studies on combined hydroseeding with coconet may consider variable slopes and different length to width and depth dimensions. Other plant varieties

Table 6. Effectiveness of Hydroseeding with Coconet Reinforcement versus Bare Soil

well as by the coconet that were put in place to hold the soil and control soil erosion.

Bare Soil 21.49 ± 28.26 563.95 ± 2457.47

Coconet 1.56 ± 11.57 5.72 ± 143.77

Table 5. Total Sediment Concentration (g/L) and Sediment Yield (g/m2h)

with coconet reinforcement is an effective soil erosion control instrument.

Fig. 11. Mean Sediment Concentrations of Bare Soil and Combination of Hydroseeding with Coconet Reinforcement


Table 4. Mean Sediment Yield of Bare Soil and Combination of Hydroseeding with Coconet Reinforcement

The value projected in the Table 4 and Fig. 12 show that the mass of the bare soil with respect to the plot area and time is definitely greater than of the Hydroseeding with Coconet reinforcement.

Fig. 12. Mean Sediment Yield of Bare Soil and Combination of Hydroseeding with Coconet Reinforcement

The following discussions summarize the total sediment concentration and total sediment yield.

Table 5 compares the sediment concentration and sediment yield of bare soil and hydroseeding with coconet reinforcement. From the numerical value indicated above, it was found out that the Hydroseeding with Coconet reinforcement lessen the mass of the soil eroded.


Table 5. Total Sediment Concentration (g/L) and Sediment Yield (g/m2h)

Table 6 presents the effectiveness of the applied hydroseeding with coconet reinforcement to control against soil erosion. From the results, it was found out that combined hydroseeding with coconet reinforcement is an effective soil erosion control instrument.


Table 6. Effectiveness of Hydroseeding with Coconet Reinforcement versus Bare Soil Against Soil Erosion (%)
