Sedimentary evolution and ecosystem change in Ahémé lake, south-west Benin

© Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License.International audienc

Erosion, suspended sediment transport and sedimentation on the Wadi Mina at the Sidi M’Hamed Ben Aouda dam, Algeria

International audienc

Recent Geochemical and Grain Size Distribution of Terrestrial Sediment in Coastal Area from the Watershed of Medjerda River, Gulf of Tunis

International audienc

Modeling of discharge and sediment transport through the SWAT model in the basin of Harraza (Northwest of Algeria)

The objective of this study is to model discharge and solid erosion quantification through a small agricultural watershed by applying the SWAT model (Soil and Water Assessment Tools) on the Wadi Harraza’s basin of which is part of Wadi Cheliff’s basin, with an average altitude of 500 m, drains an area of 568 sq km. Soil and Water Assessment Tool (SWAT, version 2009) model integrated with Geographic Information System (ArcGIS, version 10.0) were used to simulate the discharge and sediment concentration of Wadi Harraza’s basin for the period from 2004 to 2009. Model calibration and validation were performed for monthly time periods using Sequential Uncertainty Fitting 2 (SUFI-2, version 2) within SWAT-CUP. Our calibration and validation outputs for monthly simulation showed a good model performance for discharges. Thus the evolution of the average total annual sediment in the Wadi Harraza’s basin which will be deposited in the Wadi Cheliff, is estimated at 54.24 t ha−1. Keywords: SWAT model, Basin, Wadi Harraza, SUFI-2, Discharges, Sedimen

Progradation and retrogradation of the Medjerda delta during the 20th century (Tunisia, western Mediterranean)

(IF 1.84 [2018]; Q2)International audienc

The sedimentological changes caused by human impact at the artificial channel of Medjerda-River (Coastal zone of Medjerda, Tunisia)

Recent sedimentary and morphological changes at the new mouth of Medjerda-River (Gulf of Tunis) are investigated using a multiproxy approach of sediment cores complited by 210Pbex and 137Cs method dating. The subject of the study is to focus on surveying the sedimentary evolution of Medjerda-Raoued Delta caused by the human intervention in the management of the main tributaries of the Medjerda-River (artificial channel of Henchir Tobias). Sediment cores (CEM-1 and CEM-3) were subjected to both multiproxy approaches (Grain size, geochemical analysis and dating radiometric 210Pbex and 137Cs). The sedimentological analysis of the new deltaic deposits shows a progradation sequence with the silt and clay deposits on the historic sandy substratum. The mean grain size evolution on the old beach profile shows a decreasing trend from backshore (CEM-3) to nearshore (CEM-1). The geochemical results show varying concentrations of chemical elements such as Fe, K, Rb, Nb, Cr, Ti, Ba, Ca, Sr, Zr, V, and potentially toxic metal trace elements such as Pb, Zn and the As. The Principal component Analysis (PCA) applied in the geochemical elements evolution confirms the marine origin of the sand deposits in the basic layers of the two cores. The chronological method (210Pbex and 137Cs) affirms that the first fluvial deposits were set up only after 1950. The sedimentological and geochemical result confirm the actual unless of coarser fluvial supplies under the human activities leading the negative coastal sediment balance and the shoreline retreat as well

Impact of Climate Variability on Hydrology of the Western Mitidja Watershed, Algeria

International audienc

Climate Forecast Perception and Needs in Wetlands: a Case Study in the Inner Niger Delta in Mali

International audienc

Using land cover changes and demographic data to improve hydrological modeling in the Sahel

International audienc

Monitoring Water Levels and Discharges Using Radar Altimetry in an Ungauged River Basin: The Case of the Ogooué

International audienc