Present-day sediment dynamics of the Sanaga catchment (Cameroon): from the total suspended sediment (TSS) to erosion balance

Abstract

Total suspended sediment (TSS) data for 1960-1970 and from recent investigations (1990-2000) are used to evaluate the variability in sediment yield of the Sanaga catchment (Cameroon) and the equivalent rates of erosion. At the annual and seasonal time scales, total suspended sediment concentrations for the Mbam sub-catchment are three to four times higher than for the Sanaga basin, reflecting the higher sensitivity of the former to erosion. Classical clockwise hysteresis loops are observed in both sub-catchments, despite a significant increase in human-induced catchment changes. At the multi-year time frame (over a 40-year period), it appears that the second half of the 1990s is marked by a downward trend in TSS. This shift is due to the control infrastructures (river impoundments and ponds) installed in certain parts of the whole catchment, combined with a drop in annual rainfall and river discharge.

Denudation rates on cratonic landscapes: comparison between suspended and dissolved fluxes, and 10Be analysis in the Nyong and Sanaga River basins, south Cameroon

“…In fact, for the large streams of the tropical zone of Africa, including those of Cameroon, the sampling technique along one vertical which is rather simple, fast and practical, gives results that are satisfactory and relatively close to those of the full solid gauging method (e.g. Olivry et al , ; Lienou et al , ; Ndam Ngoupayou et al , )…”

Assessment of Surface Water Quality of Bétaré-Oya Gold Mining Area (East-Cameroon)

“…All these points were selected based on criteria such as accessibility and their proximity or not in the vicinity of the mining sites. All of the sixteen sample points were used for physicochemical analysis (EC, turbidity, TSS, Na + , Samples were collected manually once time at <1 m depth at the centre of the river preferentially where the flow velocity was high enough to allow a good homogenization of the solid particles and dissolved materials [5]. The samples were collected in 1.5 L polyethylene bottles washed with ultrapure acid, previously rinsed with distilled and MilliQ deionized waters, and finally rinsed three Some in-situ parameters such as pH, electrical conductivity (EC) were measured on unfiltered water using calibrated WTW 315i instruments.…”

“…This is the contrary in the southern part particularly in urban areas, mostly made up of basement formations, where water tapping is mainly done by capturing of surface water, followed by their physical and chemical treatment as well as water from boreholes. However, these surface waters regularly experience a quantitative and qualitative deterioration due to human activities (urbanization, agriculture, industries and mining activities), to which can be added the phenomenon of climate change/variability [3] [4] [5]. Among these human activities, a more attention will be laid on the impact of mining on water resources, particularly on surface water.…”

Assessment of water quality in and around Jia-Bharali river basin, North Brahmaputra Plain, India, using multivariate statistical technique

“…For the present work, a detailed time schedule was prepared for collection, transportation, pre-treatment, storage and analysis of the water samples. SW samples were manually collected at a depth < 1 m in the center of the sources, preferentially where the flow velocity was high enough to allow for good homogenization of the solid particles and dissolved material (Li et al 2014;Ndam Ngoupayou et al 2016). GW samples were directly collected from shallow dug wells.…”