Abstract
The present work was carried out in the framework of the Lesotho-Italy cooperation project “Renewable Energy Maps for Lesotho,” launched in 2016, with the main purpose to produce a series of maps aimed to support the Government of Lesotho in planning and expanding the exploitation of renewable energy sources (wind, solar and hydro). A multiple regression model specifically developed for sediment yield assessment in Lesotho catchments is here presented with a view to contributing to the follow-up of development projects in the field of hydroelectric energy. The “Lesotho model,” based on observations at 16 gauging stations, takes into account the proportions of agricultural and sedimentary bedrock areas as explanatory variables. Statistical reliability tests proved the model robustness after previous models, developed at continental or sub-continental scale, revealed to be ineffective or hardly applicable. A map of simulated sediment yields at sub-catchment level is provided, as an example of model application.
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(data from FAO 2017)
(redrawn from Department of Mines and Geology 1982)
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Acknowledgements
The authors wish to thank the personnel from Lesotho Institutions (Department of Energy, Lesotho Meteorological Service, Lesotho Highlands Development Authority, Land Administration Authority, Department of Mines and Geology, Department of Water Affair, Bureau of Statistics) and from the Food and Agriculture Organization of the United Nations for providing data. Thanks to the anonymous reviewers for the suggestions that helped us to improve the paper.
Funding
This work was supported by the Italian Ministry for the Environment, Land and Sea (IMELS) in the framework of the “Memorandum of Understanding on cooperation in the field of climate change vulnerability, risk assessment, adaptation and mitigation,” signed in 2016 between IMELS and the Ministry of Energy and Meteorology of the Kingdom of Lesotho (Grant Number: I31I18001000001).
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SG contributed to conceptualization, SG, FP contributed to formal analysis and investigation, SG contributed to writing—original draft preparation, SG, FP contributed to writing—review and editing, CT contributed to material preparation and data collection.
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Grauso, S., Pasanisi, F. & Tebano, C. Modeling the suspended sediment yield in Lesotho rivers. Model. Earth Syst. Environ. 6, 759–768 (2020). https://doi.org/10.1007/s40808-020-00738-5
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DOI: https://doi.org/10.1007/s40808-020-00738-5