Assessment of the susceptibility degree to landslides within Ciulucurilor Hills by Method of Frequency Rate

Abstract

Landslide susceptibility map for Ciulucurilor Hills was carried out using frequency ratio method. Its calculation is performed by the ratio of the percentage of landslide areas for each factor taken into account (lithology, elevation, drainage depth, slope, exposition, land use, distance from river and drainage network density) and the percentage of the total area corresponding to each factor. Very low susceptibility land occupies 10.1% of the region surface and is the most common in the south-west and the Big Ciuluc and the Middle Ciuluc river valleys. There is 25.8% of the built surface on this area. Low susceptibility land occupies 40.3% of the territory, being the largest class of susceptibility. It holds 56.2% of the arable land and 47.6% of the built surface. The average susceptibility is recorded on 22.9% of the territory and has a more compact distribution in Soloneţ basin. This land holds 38.8% of the pasture surface and 28.5% of the perennial plantations. The land with high and very high susceptibility occupies 26.7% of the territory, with a high frequency in the south-west of the region, on interfluve between the Big Ciuluc and the Middle Ciuluc rivers. These classes have 81.9% of forest surface and only 12.6% of the arable land. The length of the roads located on the land with high and very high susceptibility is 164.5 km