Effects of climate and anthropogenic changes on current and future variability in flows in the So'o River Basin (south of Cameroon)

Abstract

Due to climate and environmental changes, sub-Saharan Africa (SSA) has experienced several drought and flood events in recent decades with serious consequences on the economy of the sub-region. In this context, the region needs to enhance its capacity in water resources management, based on both good knowledge of contemporary variations in river flows and reliable forecasts. The objective of this article was to study the evolution of current and future (near (2022–2060) and distant (2061–2100)) flows in the So'o River Basin (SRB) in Cameroon. To achieve this, the Pettitt and modified Mann–Kendall tests were used to analyze hydrometeorological time series in the basin. The Soil and Water Assessment Tool (SWAT) model was used to simulate the future flows in the SRB. The results obtained show that for the current period, the flows of the So'o decrease due to the decrease in precipitation. For future periods, a change in precipitation in line with the predictions of the CCCma model will lead to a decrease in river discharge in the basin, except under the RCP8.5 scenario during the second period (2061–2100), where will note an increase compared to the historical period of approximately +4%. Results from the RCA4 model project an increase in precipitation which will lead to an increase in river discharge by more than +50%, regardless of the period and the scenario considered. An increase in discharges was noted in some cases despite a drop in rainfall, particularly in the case of discharges simulated for the second period (2061–2100) from the outputs of the CCCma model. This seems to be a consequence of the increase in impervious spaces, all the more the runoff increases during this period according to the model. Results from this study could be used to enhance water resources management in the basin investigated and the region.

Impact of climate and anthropogenic changes on current and future variability in flows in the Nyong River Basin (equatorial central Africa)

“…The SWAT model has been widely used around the world for hydrological simulations of basins with different environmental conditions (climate, topography, geology, soils and vegetation) (Von Stackelberg et al 2007;Andrade et al 2013;Pereira et al al. 2014;Ebodé et al 2022b) with satisfactory results obtained. For SWAT to become a universal hydrological model, more studies are needed in basins with climatic regimes and soils typical of equatorial conditions, such as that of the Nyong basin in southern Cameroon.…”

Hydrological variability and flood risk in a forest watershed undergoing accelerated urbanization: the case of Mefou (South Cameroon)

“…Few authors in sub-Saharan Africa for example (D'Orgeval and Polcher, 2008; Amogu et al, 2010) have assessed the hydrological impacts of human-induced environmental changes. Likewise, studies that attempted to dissociate the latter from those arising from exclusively hydro-climatic uctuations are quantitatively limited in Central Africa (Dzana et al 2011;Ebodé 2022;Ebodé et al 2022a;Ebodé et al 2022b). However, there is no doubt that anthropogenic actions through urbanization and industrial agriculture, which have resulted in large-scale deforestation, have increased considerably over the past thirty years throughout Sub-Saharan Africa and even beyond.…”

Analysis of the Spatio-temporal Rainfall Variability in Cameroon over the Period 1950 to 2019

“…Let us briefly recall that after the 1990s, long-time series of rainfall became rare in sub-Saharan Africa. This scarcity of data is marked even more in Central Africa [11][12]. The active network now only includes 35 stations in the DRC (i.e.…”