A dynamic land use/land cover input helps in picturing the Sahelian paradox: Assessing variability and attribution of changes in surface runoff in a Sahelian watershed.
Autor: | Yonaba R; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso. Electronic address: ousmane.yonaba@2ie-edu.org., Biaou AC; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso., Koïta M; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso., Tazen F; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso., Mounirou LA; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso., Zouré CO; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso., Queloz P; Institute of Territorial Engineering (INSIT), School of Management and Engineering Vaud (HEIG-VD), Yverdon-les-Bains, Switzerland., Karambiri H; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso., Yacouba H; Laboratory of Water, Hydro-Systems and Agriculture (LEHSA), International Institute for Water and Environmental Engineering (2iE), 01 PO Box 594, Ouagadougou 01, Burkina Faso. |
---|---|
Jazyk: | angličtina |
Zdroj: | The Science of the total environment [Sci Total Environ] 2021 Feb 25; Vol. 757, pp. 143792. Date of Electronic Publication: 2020 Nov 27. |
DOI: | 10.1016/j.scitotenv.2020.143792 |
Abstrakt: | In Sahelian landscapes, land use/land cover (LULC) dynamics and climate variability are already known to affect the water cycle. In its current practice however, hydrological modelling does not account for LULC changes. This issue pertains to rapidly evolving watersheds and might result in critical inaccuracies in the simulated processes. In this study, the Soil and Water Assessment Tool (SWAT) model was used to simulate surface runoff in the small Sahelian watershed of Tougou, which underwent significant LULC changes between 1952 and 2017. Based on rainfall/runoff data acquired from 2004 to 2018, the SWAT model was calibrated under two scenarios: a static land use scenario (SLU) using a single LULC map (in 1999) and a dynamic land use scenario (DLU) integrating 3 LULC maps (1999, 2009 and 2017). The DLU scenario estimated with higher accuracy surface runoff, deep aquifer infiltration and actual evapotranspiration processes. Based on the calibrated parameters, surface runoff was simulated during the historical period 1952-2003 under four scenarios with static LULC maps (in 1952, 1973, 1986 and 1999) opposed to a fifth scenario integrating these LULC maps dynamically. The DLU scenario was found to be more effective at picturing the so-called Sahelian paradox (i.e. the increase in surface runoff despite the decrease in rainfall), reported in the literature for small watersheds in the Sahel. The analysis of variability revealed that fluctuations in surface runoff were both influenced by rainfall and LULC changes. Furthermore, the isolated contributions of climate variability and LULC changes on surface runoff showed that LULC conditions played a dominant role (η Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. (Copyright © 2020 Elsevier B.V. All rights reserved.) |
Databáze: | MEDLINE |
Externí odkaz: |