Integrating environmental information in gully initiation topographic thresholds: application to three regions in Wallonia (Belgium)
(2012) PhD Student Day ENVITAM — Location: Espace Senghor, Gembloux (8.February.2012)
Files
No attached file found for this publication.
Details
- Authors
- Abstract
- Gully erosion is responsible for 20% to 80% of the total soil erosion by water in Belgium and causes serious damages. In order to explain and predict the initiation of gully erosion, many studies have focused on topographic thresholds which depend on the contributing area and slope at the gully head. However, this approach does not integrate specific environmental information such as soil type and land use. Furthermore, several methods exist to determine the threshold. This study proposes a simple methodology to integrate soil and land use information in the topographic thresholds and compares the two main approaches used for drawing gully initiation thresholds. This methodology is applied to 3 agro-pedological regions of Wallonia (Belgium). For each region, a gully database was created by digitizing gullies on the basis of aerial photographs. Slopes and contributing areas at the gully heads as well as land use and soil type in the contributing areas were extracted. Using this information, runoff volumes were calculated using the SCS Curve Number method. Gully initiation thresholds defined using slope and runoff volume are compared with thresholds based on slope and contributing area. The former approach is better able to discriminate among contributing areas that have heterogeneous land uses and soil types. We found that regional differences in topographic and environmental conditions lead to differences in the thresholds. These differences are dependent on the type of thresholding method used. . The observed differences are sensitive to the method used for drawing the threshold.
- Affiliations
Citations
Maugnard, A., & Bielders, C. (2012). Integrating environmental information in gully initiation topographic thresholds: application to three regions in Wallonia (Belgium). In Vanclooster M. (ed.), Proceedings (p. p. 61). https://hdl.handle.net/2078.5/251478