Impact of upstream sediment inflow on headcut morphodynamics

• Autorzy: Wells R. R. , Bennett S. J. , Alonso C. V.
• Języki publikacji: EN

Abstrakty

EN

Headcut erosion can severely accelerate soil loss in upland concentrated flows and lead to significant soil degradation in agricultural areas. Previous experimental work has demonstrated that actively migrating headcuts display systematic morphodynamic behavior, and impinging jet theory can provide an excellent theoretical foundation for this erosional phenomenon. This research sought to examine systematically the effect of an upstream sediment inflow on the morphodynamics of actively migrating headcuts in upland concentrated flows. Using a specially designed experimental facility, actively migrating headcuts were allowed to develop, and then subjected to an upstream sediment load composed of sand. As the upstream sediment feed rate increased, the size and migration rate of the headcut decreased markedly, but sediment discharge was less affected. The headcut erosion process was arrested as sediment inflow rates increased above a threshold value. As sediment feed rate upstream of the headcut increased, sediment size fraction downstream of the headcut also increased. This research suggests that headcut erosion can be greatly modulated by an upstream sediment source, further complicating the prediction of soil erosion on upland areas.

Słowa kluczowe

EN

headcuts; overland flow; simulated rainfall; soil erosion

• Wydawca: Stowarzyszenie Geomorfologów Polskich
• Czasopismo: Landform Analysis
• Rocznik: 2011
• Tom: Vol. 17
• Strony: 225--227
• Opis fizyczny: Bibliogr. 7 poz., rys.

Twórcy

autor

Wells R. R.

autor

Bennett S. J.

autor

Alonso C. V.

• USDA-ARS National Sedimentation Laboratory USA,

Bibliografia

• Bennett S.J., 1999. Effect of slope on the growth and migration of headcuts in rills. Geomorphology 30:273–290.
• Bennett S.J., Alonso C.V., Prasad S.N. & Römkens M.J.M., 2000. Experiments on headcut growth and migration in concentrated flows typical of upland areas. Water Resour. Res. 36: 1911–1922.
• Bennett S.J. & Casalí J., 2001. Effect of initial step height on headcut development in upland concentrated flows. Water Resour. Res. 37: 1475–1484.
• Gordon L.M., Bennett S.J., Wells R.R. & Alonso,C.V., 2007. Effect of soil stratification on the development and migration of headcuts in upland concentrated flows. Water Resour. Res. 43:
• Li G. & Abrahams A.D., 1997. Effect of saltating sediment load on the determination of the mean velocity of overland flow. Water Resourc. Res. 33: 341–347.
• Wells R.R., Alonso C.V. & Bennett S.J., 2009a. Morphodynamics of headcut development and soil erosion in upland concentrated flows.Soil Sci. Soc. Am. J., 73 (2): 521–530.
• Wells R.R., Bennett S.J. & Alonso C.V., 2009b. Effect of soil texture, tailwater height, and pore-water pressure on the morphodynamics of migrating headcuts in upland concentrated flows. Earth Surf. Proc. Landf. 34: 1867–1877.