DBPapers
DOI: 10.5593/sgem2017/23/S11.076

MONITORING THE EVOLUTION OF GULLIES IN A WATER CATCHMENT BY GIS TECHNIQUES

G. Biali, P. Cojocaru
Thursday 14 September 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgem.org, SGEM2017 Conference Proceedings, ISBN 978-619-7408-03-4 / ISSN 1314-2704, 29 June - 5 July, 2017, Vol. 17, Issue 23, 611-618 pp, DOI: 10.5593/sgem2017/23/S11.076

ABSTRACT

This paper presents a case study regarding the GIS applications on the slopes with frequent erosion processes in depth. Monitoring the gullies consists in identifying them in the land, their positioning on the map, their classification and recording according to several indicators and following their evolution in time. The study is carried out in a water catchment area of 4,665 ha in Berheci Superior, Bacau county, Romania. By using ortophoplanes, satellite images or air-photograms (in some cases) and the documentation in the land, it was possible to map the gullies 72 gullies are taken into account. By GIS techniques, we model and create informational layers regarding the following parameters in the studied water catchment: the way of using the lands, the lithology, elevation, orientation of slopes, the land slope, and the density of relief fragmentation (Rus M.,2015, Kerekes A.H.,2016). The work method suggested in this study is applying the model of frequency ratio (Frequency Ratio Model) in ArcGIS. The most important layer resulted contains information about the susceptibility of the lands to gully formation, when natural factors are taken into account. In this application, the (negative) contribution of the anthropogenic factor is not under study. The GIS analysis in this paper regarding the susceptibility of the slopes to gully formation has indicated a relatively high share of the stable lands (62.4%). By this study, we want to suggest the best measure to fight erosion in depth, in order to protect agricultural lands affected by ravine formation.

Keywords: gullies, GIS, modelling natural factors, digital maps