Sediment Transport and Rainfall Erosivity Evolution in Twelve Basins in Central and Western Algeria

Abstract

Abstract:Soil erosion by rain and surface runoff is an important problem in the Mediterranean countries. The study of the relationship between erosion and sediment transport with hydrological and climatic factors have been conducted in many countries around the world. The aim of this work is to show rainfall impact on the variability of spatial and temporal concentration in twelve drainage basins in the west of Algeria. We will also seek to find a representative parameter of rainfall erosive potential on a Time and spatial scale. When studying sediment transport in twelve drainage basins of the Centre and the west of Algeria, we have found that the modified Fournier index Which explains much of the specific degradation compared to the Fournier index. The study of the temporal variability of the annual rainfall series, modified Fournier index and concentration of the precipitation in the year for a series from 1930 to 2007 showed a negative trend of the two variables. The annual rainfall and modified Fournier index have declined by more than 20%. This decline is more significant in inland areas.

Analysis of Costantino Landslide Dam Evolution (Southern Italy) by Means of Satellite Images, Aerial Photos, and Climate Data

“…This result agrees with those obtained in other areas of the Mediterranean basin (e.g. [75][76][77][78]), but is in contrast to findings in the Mediterranean Iberian peninsula, where some increase (+8.8%) of MFI was observed (e.g. [73]).…”

Spatial and temporal variability of the rainfall erosivity factor in Northern Algeria

“…These high plateaus narrow to the east due to their proximity with the Tell Atlas. Their elevation decreases to 400 m at Chott El Hodna (Meddi 2013). These highlands form natural barriers to rainproducing cloud masses (Laborde 1993;Meddi et al 2002) showed that much of the rainfall variability is explained by elevation and the landscape.…”

“…In the Tell Atlas plains, rainfall ranges from 500 in the west to 450 mm in the center and 700 mm in the east. In the Saharan Atlas, the climate is very hot and dry in summer and mild in winter, with lower rainfall compared to the north, owing to its greater distance from the sea (Meddi 2013). …”

“…A series of mountains formed by the Mitidja Atlas (1972 m) begins to the east of Djebel Zekkar, followed further east by the Kabylie highlands (Djurdjura, 2328 m). The Tell Atlas also includes coastal plains such as the Oran, Mitidja, and Annaba plains, and inland plains such as the Tlemcen, Sidi Bel Abbess, and Sersou plains (Meddi 2013). The high plateaus spread out over approximately 700 km from west to east, with elevations ranging from 1000 to 1200 m. These djebels include Djebel Tlemcen (1142 m).…”

“…In contrast to Meddi (2013), hourly rainfall values are used in the present study to calculate R in the universal equation for Northern Algeria. In Meddi et al (2013), rainfall erosivity was incorporated using the modified Fournier index.…”