摘要:Abstract
The purpose of this study is to bring a series of changes to the potential flashed-flood index proposed and used by Smith (2003), to estimate floodplains in the upper part of Trotus Basin. Trotuş Basin is located in the central - eastern part of the Eastern Carpathians (Romania) having an area of 4.456 km2. The Trotus Basin is recognized as a basin where floods occur frequently due to climatic factors (precipitation, air temperature and winds) as well as due to the morphological characteristics (altitude, slope and versants orientation) that favour the formation of these phenomena. To develop a modified Flash Flood Potential Index was used six physical-geographical factors: land use, soil texture, rock’s permeability, slope, profile curvature and flow accumulation. Each thematic layer has been classified in five classes, from 1 to 5, where 1 means a low contribution and 5 a strong contribution of factors in water accumulation and each factor was weighted according to its importance. The result was a grid layer representing the flood potential index. The maximum flood hazard was associated with an area of approximate 10% from the studied surface. To see the contribution of each factor in the achievement of this index a multiple linear regression was made. The result shows that three variables are statistically significant and explain 91.6% from the model. This means that MFFPI can be obtained only from these three significant factors (flow accumulation, profile curvature and land cover) in order to identify areas with flood predisposition, the non-significant variables being removed. In order to verify these results the obtained MFFPI was compared with the flood hazard map for this area and the procedure showed that this index can be used in the identification of the flood-predisposed areas.