The Rainsplash Effect on Varying Slopes

Ashley Desmond

Dave Brennan

December 5, 2001

Centennial WoodsBurlington, VT

Goals:

The purpose of our project was to determine the extent which these factors control erosion:

- Vegetation- Slope Angle- Precipitation

TRENCH SETUP AND SITES

METHODS OF SEDIMENT EXTRACTION

Site Descriptions

Site 1 and site 2 had similar slope angles

Site 3 had a dramatically steeper slope than did sites 1 and 2

Site 2 was densely vegetated, sites 1 and 3 were not

Sediment Totals and Ratios

Site 1: 1.05 .42 .33 3.76% 8.73%

Site 2 : 1.98 1.27 .60 8.05% 12.80%

Site 3 : 18.62 16.14 7.43 88.19% 4.45%

Trial 1 Trial2 Trial3% of total sediment L.O.I.

In (g)

s e d im e n t c o l le c t e d v s . s lo p e a n g le

0

5

1 0

1 5

2 0

2 0 2 5 3 0 3 5 4 0 4 5

s lo p e a n g l e ( d e g r e e s)

Figure 6

Figure 6: The graph shows how slope angle affects the amount of sediment collected. The greater the slope angle, the more sediment that is propelled downslope by raindrops.

Site 3

Site 2 Site 1

sediment collected (g)

SEDIMENT VS. SLOPE ANGLESEDIMENT vs. SLOPE ANGLE

CONCLUSIONS

- Rainsplash is the main erosion mechanism

- Slope angle is the dominant characteristic effecting quantities of eroded sediment

- Vegetation appears to play a minimal role in controlling sediment collection

- Precipitation relates to rainsplash, therefore more precipitation leads to more sediment collected