DBPapers
DOI: 10.5593/sgem2017/51/S20.055

EVALUATION OF POTENTIAL GROWTH OF GULLY LENGTH ON HILLSIDE CATCHMENTS IN THE SOUTH OF WESTERN SIBERIA (BIYA-CHUMYSH ELEVATION AS A CASE STUDY)

V. Skripko
Wednesday 13 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-08-9 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 51, 417-424 pp, DOI: 10.5593/sgem2017/51/S20.055

ABSTRACT

The development of gully erosion is an urgent problem in many parts of the world. The southern part of Western Siberia belongs to the Russian regions with an extensive development of gully erosion. The occurrence of erodible loess deposits on the earth’s surface, the rugged topography, the climate characteristics (a considerable reserve of water in the snow, intensive spring snowmelt, and heavy rains) in combination with a high plough-disturbance of territories create favorable conditions for the formation and development of gullies. Therefore, the identification of potential growth of gullies on the slopes is a problem of great theoretical and practical importance. The potential growth of the gully length was evaluated in one of the most developed agricultural areas in the piedmont plains of the south of Western Siberia, the Biya-Chumysh elevation. The evaluation is based on the E. F. Zorina methodology (2003). To calculate the potential length of the gully, the individual elementary watersheds on the slopes of river valleys (catchment areas of gullies) were chosen as territorial cells. According to the model, to calculate the potential length of the gully, the morphometric parameters of erosion catchment (such as length, slope, erosion base level, the surface area and conditions in coefficients), flow rate, water flow at the outlet and the data on erosion resistance of soils (erosive velocity of water flow) are used. The morphometric characteristics of the topography are calculated using GIS based on the topographic map. Other parameters are estimated in accordance with the regulations and instructions as well as with the available data on the study region. The potential growth of gully length is evaluated by the example of the four key sites located in the central part of the Biya-Chumysh elevation. The simulation found that the length of potential gullies, which may form in case of the disturbance of soil-vegetation cover, can vary from 20% to 80% of the length of the catchment area. The calculated potential length of gullies in the watershed correlates well with the length of the channels of temporary flows, morphologically expressed in contour line. It suggests that during the initial formation of the hillside catchment on slopes of river valleys the frequency and intensity of heavy rains significantly exceeded the current values.

Keywords: gullies, potential length of gullies, hillside catchments, slopes of river valleys, the south of Western Siberia