VULNERABILITY TO SURFACE EROSION DUE TO RAINFALLS AND RELIEF PUBLISHEDSilvica ONCIA, Loredana COPACEAN
The main purpose of this study is to analyze the vulnerability of the Bara territory (located in the low hills, with altitudes between 128 - 278 m.) to the action of erosion processes under the influence of precipitation, slope and slope orientation. To analyze the climate of the study area were used meteorological data recorded at the meteorological station Lugoj in the period 1980 - 2010 and in 2010. Based on this data were calculated de Martonne Aridity Index, Angot Index, Fournier Index. Using Digital Elevation Model was generated, by ArcGIS software, map of the slopes and aspect, used to identify areas vulnerable to the action of surface erosion and to establish correlations between the slope and slope exposure. In 2010, de Mrtonne Index was 34.44 for the type of humid climate. Fourier Index has a value of 31.85, which means that, in 2010, the potential erosion by rainfall falls in the "very low", but the temporal distribution of rainfall is uneven and the Angot Index highlighting rainy periods, favorable production erosion processes, in spring and early summer. The interval from April to June can be considered critical erosion season, in this range falls 38.81% of annual precipitation. In terms of slope gradient, approximately 85% of the Bara teritory is vulnerable across the occurrence of erosion processes. Assuming that surface erosion occurs more intensely on the slopes with predominantly southern exposure, 35% of the total area (land with orientation SE, S, SW) shows greater vulnerability. Category slope from 5.01 - 20% has the largest share in the total area of each orientation class values ranging between 75.14 - 82.70%; the largest areas with slopes in the range mentioned are on the slopes NW and E and the lower slopes oriented N.
risk, erosion, rainfall, slope, orientation