In collaboration with Iranian Watershed Management Association

Document Type : Research Paper

Authors

1 PhD Student,, Faculty of Natural Resources and Earth sciences, University of Kashan, Iran

2 Assistant Professor, Faculty of Natural resource and earth sciences, University of Kashan, Iran

Abstract

Ephemeral Gully (EG) erosion is one of the most destructive types of water erosion, which contributes significantly to land degradation. EG erosion prediction is necessary to assess the magnitude of soil loss and to implement the appropriate conservation measures. The aim of current study  was to evaluate the efficiency of EGEM model for EG erosion prediction in Ghoorichay Watershed, Ardabil Province, Iran. For this purpose, a number of 17 EG erosion was identified and monitored between the years 2014 to 2016. The morphological characteristics and erosion rate of EGs were measured and recorded after seven effective rainfall events. In order to calculate the EG erosion, EGEM model requires four major categories of input data, including identification information, watershed data, soil data, and rainfall data. The model has two major components: hydrology and erosion. The runoff induced by a rainfall event in each gully catchment was determined by the Natural Recourses Conservation service (NRCS) Curve Number (CN). The result of EGEM model performance evaluation showed that the eroded soil volume and cross-section were predicted with a determination coefficient of 0.96 and 0.89, respectively. Sensitivity analysis revealed that the curve number was the most sensitive parameter, so that, with a 10% increasing and decreasing in CN, the volume of soil loss varied 22.98 and -18.92%, respectively. It can be concluded that EGEM model was suitable for event-based EG erosion prediction in Ghoorichay Watershed and it can be recommended for studying and planning on EGs in similar watersheds.

Keywords

  1. Bernard, J., R.L. Bingner, S.M. Dabney, E.J. Langendoen, J. Lemunyon, W. Merkel, F. Theurer, R.R. Wells, N. Widman and G.V. Wilson. 2010. Ephemeral gully erosion: a natural resource concern. USDA-ARS National Sedimentation Laboratory Research Report. No. 69. US Department of Agriculture, Agricultural Research Service, National Sedimentation Laboratory, Oxford, MS.
  2. Bingner, R.L., R.R. Wells, H.G. Momm, J.R. Rigby and F.D. Theurer. 2016. Ephemeral gully channel width and erosion simulation technology. Natural Hazards, 80(3): 1949-1966.
  3. Capra, A., L.M. Mazzara and B. Scoicolone. 2005. Application of the EGEM model to predict ephemeral gully erosion in Sicily, Italy. Catena, 59: 133-146.
  4. Foster, G.R. and L.D. Meyer. 1975. Mathematical simulation of upland erosion by fundamental erosion mechanics. American Society of Mechanical Engineers, 1975: 190-207.
  5. Franti, T.G., J.M. Laflen and D.A. 1985. Soil credibility and critical shear under concentrated flow. ASAE Summer Paper, 85: 20-33.
  6. Gordon, L.M., S.J. Bennett, R.L. Bingner, F.D. Theurer and C.V. Alonso. 2007. Simulating ephemeral gully erosion in AnnAGNPS. American Society of Agricultural and Biological Engineers, 50(3): 857–866.
  7. Gudino Elizondo, N., T.W. Biggs, C. Castillo, R.L. Bingner, E.J. Langendoen, K.T. Taniguchi, T. Kretzschmar, Y. Yuan and D. Liden. 2018a. Measuring ephemeral gully erosion rates and topographical thresholds in an urban watershed using unmanned aerial systems and structure from motion photogrammetric techniques. Land Degradation and Development, 29(6): 1896-1905.
  8. Gudino-Elizondo, N., T. Biggs, R. Bingner, Y. Yuan, E. Langendoen, K. Taniguchi, T. Kretzschmar, E. Taguas and D. Liden. 2018b. Modelling ephemeral gully erosion from unpaved urban roads: equifinality and implications for scenario analysis. Geosciences, 8(4): 137-153.
  9. Gutiérrez, Á.G., S. Schnabel and J.F.L. Contador. 2009. Using and comparing two nonparametric methods (CART and MARS) to model the potential distribution of gullies. Ecological Modelling, 220(24): 3630-3637.
  10. Nachtergaele, J.J., L. Poeson, D. Vandekerckove, W. Oostwoud and M. Roxo. 2001. Testing the Ephemeral Gully Erosion Model (EGEM) for two Mediterranean environments. Earth Surface Processes and Land Forms, 26: 17–30.
  11. Poesen, , G. Nachtergaele, C. Verstraten and C. Valentine. 2003. Gully erosion and environmental change: importance and research needs. Catena, 50(2–4): 91–133.
  12. Renard, K.G., G.R. Foster, G.A. Weesies, D.K. McCool and D.C. Yoder. 1997. Predicting soil erosion by water: a guide to conservation planning with the Revised Universal Soil Loss Equation (RUSLE) (Vol. 703). Washington, D.C., United States Department of Agriculture, 49 pages.
  13. Rezaei Moghadam, M.H. and A. Behboodi. 2011. Application of EGEM model for ephemeral gully erosion estimation in Sarandchay Watershed. Journal of Geographic Space, 11(35): 135-154 (in Persian).
  14. Samani, A.N., R.J. Wasson, M.R. Rahdari and A. Moeini. 2016. Quantifying eroding head cut detachment through flume experiments and hydraulic thresholds analysis. Environmental Earth Sciences, 75(21): 1424-1443.
  15. Tekwa, I.J. and A.S. Yahya. 2014. Sensitivity analysis of some EGEM inputs in predicting ephemeral gully erosion in Mubi, semi-arid Northeast Nigeria. Asian American Environment and Agriculture Research Journal, 1(1): 1-12.
  16. Tekwa, I.J., A.M. Kundiri and A.M. Chiroma. 2016. Efficiency test of modeled empirical equations in predicting soil loss from ephemeral gully erosion around Mubi, Northeast Nigeria. International Soil and Water Conservation Research, 4(1): 12-19.
  17. Tekwa, I.J., J.M. Laflen and A.M. Kundiri. 2015. Efficiency test of adapted EGEM model in predicting ephemeral gully erosion around Mubi, Northeast Nigeria. International Soil and Water Conservation Research, 3(1): 15-27.
  18. USDA-ARS, 1980. CREAMS, a field scale model for chemicals, runoff, and erosion from agricultural management systems. United States, Science and Education Administration, Agricultural Research Service, Science and Education Administration, 672 pages.
  19. 1992. Ephemeral Gully Erosion Model (EGEM). Ver. 2.0, DOS User Manual, Soil Conservation Service, Washington, D.C., pp. 101.
  20. Watson, D., J. Laflen and T. Franti. 1985. Ephemeral gully erosion estimator. 70th SWCS International Annual Conference, July 26-29, Greensboro.
  21. Wilson, G. 2011. Understanding soil-pipe flow and its role in ephemeral gully erosion. Hydrological Processes, 25: 2354–2364.
  22. Wolf, B. 2003. Diagnostic techniques for improving crop production. Haworth Press, USA, 452 pages.
  23. Woodward, D.E. Method to predict cropland ephemeral gully erosion. Catena, 37: 393–399.
  24. Zarei, H., A. Najafinejad, M. Hosseinalizadeh and K. Alipour. 2017. Efficiency assessment of the EGEM to estimate gully erosion in Iky-Aghzly Watershed of Golestan Province. Journal of Water and Soil Conservation, 24(5): 147-162 (in Persian).